Litter production, components and dynamics were investigated and forest floor litter was quantified throughout awhole year in three subalpine forests, dominated by tree species of spruce (SF), fir (FF) and birch (BF),...Litter production, components and dynamics were investigated and forest floor litter was quantified throughout awhole year in three subalpine forests, dominated by tree species of spruce (SF), fir (FF) and birch (BF), in WesternSichuan, China, in order to understand the key factors that influenced litter production and dynamics. Litterfall in thethree forests consisted mainly of leaves, woody litter, reproductive organs and moss. Contribution of leaf litter to thetotal litterfall was significantly (P < 0.05) greater than that of woody litter, reproductive organs or moss. Regardlessof the stands, litterfall exhibited a marked monthly variation with the maximum litterfall peaks occurring in October,with smaller peaks occurring in February for SF and FF, and May for BF. The analysis indicated that tree species,stand density, leaf area index (LAI), stand basal area and stand age were the key factors determining litter production.Meanwhile tree species and phenology controlled the litter dynamics, with wind and snow modifying the litter componentsand dynamics.展开更多
Macronutrients （N, P, K, Ca, Mg, and S） in litter of three primarily spruce （Picea purpurea Masters） （SF）, fir （Abies faxoniana Rehder ＆ E. H. Wilson） （FF）, and birch （Betula platyphylla Sukaczev） （BF） ...Macronutrients （N, P, K, Ca, Mg, and S） in litter of three primarily spruce （Picea purpurea Masters） （SF）, fir （Abies faxoniana Rehder ＆ E. H. Wilson） （FF）, and birch （Betula platyphylla Sukaczev） （BF） subalpine forests in western China were measured to understand the monthly variations in litter nutrient concentrations and annual and monthly nutrient returns via litteffall. Nutrient concentration in litter showed the rank order of Ca 〉 N 〉 Mg 〉 K 〉 S 〉 P. Monthly variations in nutrient concentrations were greater in leaf litter （LL） than other litter components. The highest and lowest concentrations of N, P, K, and S in LL were found in the growing season and the nongrowing season, respectively, but Ca and Mg were the opposite. Nutrient returns via litterfall showed a marked monthly pattern with a major peak in October and one or two small peaks in February and/or May, varying with the element and stand type, but no marked monthly variations in nutrient returns via woody litter, reproductive litter, except in May for the BF, and moss litter. Not only litter production but also nutrient concentration controlled the annual nutrient return and the monthly nutrient return pattern. The monthly patterns of the nutrient concentration and return were of ecological importance for nutrient cycling and plant growth in the subalpine forest ecosystems.展开更多
Grazing exclusion using fences is a key policy being applied by the Chinese government to rehabilitate degraded grasslands on the Tibetan Plateau(TP)and elsewhere.However,there is a limited understanding of the effect...Grazing exclusion using fences is a key policy being applied by the Chinese government to rehabilitate degraded grasslands on the Tibetan Plateau(TP)and elsewhere.However,there is a limited understanding of the effects of grazing exclusion on alpine ecosystem functions and services and its impacts on herders’livelihoods.Our meta-analyses and questionnaire-based surveys revealed that grazing exclusion with fences was effective in promoting aboveground vegetation growth for up to four years in degraded alpine meadows and for up to eight years in the alpine steppes of the TP.Longer-term fencing did not bring any ecological and economic benefits.We also found that fencing hindered wildlife movement,increased grazing pressure in unfenced areas,lowered the satisfaction of herders,and rendered substantial financial costs to both regional and national governments.We recommend that traditional free grazing should be encouraged if applicable,short-term fencing(for 4-8 years)should be adopted in severely degraded grasslands,and fencing should be avoided in key wildlife habitat areas,especially the protected large mammal species.展开更多
Age-related macular degeneration (AMD) is a complex eye disorder and is the leading cause of incurable blindness worldwide in the elderly. Clinically, AMD initially affects the central area of retina known as the macu...Age-related macular degeneration (AMD) is a complex eye disorder and is the leading cause of incurable blindness worldwide in the elderly. Clinically, AMD initially affects the central area of retina known as the macula and it is classified as early stage to late stage (advanced AMD). The advanced AMD is classified into the nonexudative or atrophic form (dry AMD) and the exudative or neovascular form (wet AMD). More severe vision loss is typically associated with the wet form. Multiple genetic factors, lipid metabolism, oxidative stress and aging, play a role in the etiology of AMD. Dysregulation in genetic to AMD is established to 46%–71% of disease contribution, with CFH and ARMS2/HTRA1 to be the two most notable risk loci among the 103 identified AMD associated loci so far. Chronic cigarette smoking is the most proven consistently risk living habits for AMD. Deep learning algorithm has been developed based on image recognition to distinguish wet AMD and normal macula with high accuracy. Currently, anti-vascular endothelial growth factor (VEGF) therapy is highly effective at treating wet AMD. Several new generation AMD drugs and iPSC-derived RPE cell therapy are in the clinical trial stage and are promising to improve AMD treatment in the near future.展开更多
The recent novel coronavirus disease(COVID-19)outbreak,caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is seeing a rapid increase in infected patients worldwide.The host immune response to SARS-C...The recent novel coronavirus disease(COVID-19)outbreak,caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is seeing a rapid increase in infected patients worldwide.The host immune response to SARS-CoV-2 appears to play a critical role in disease pathogenesis and clinical manifestations.SARS-CoV-2 not only activates antiviral immune responses,but can also cause uncontrolled inflammatory responses characterized by marked pro-inflammatory cytokine release in patients with severe COVID-19,leading to lymphopenia,lymphocyte dysfunction,and granulocyte and monocyte abnormalities.These SARS-CoV-2-induced immune abnormalities may lead to infections by microorganisms,septic shock,and severe multiple organ dysfunction.Therefore,mechanisms underlying immune abnormalities in patients with COVID-19 must be elucidated to guide clinical management of the disease.Moreover,rational management of the immune responses to SARSCoV-2,which includes enhancing anti-viral immunity while inhibiting systemic inflammation,may be key to successful treatment.In this review,we discuss the immunopathology of COVID-19,its potential mechanisms,and clinical implications to aid the development of new therapeutic strategies against COVID-19.展开更多
Synthetic hexaploid wheat （Triticum turgidum x Aegilops tauschii） was created to explore for novel genes from T. turgidum and Ae. tauschii that can be used for common wheat improvement. In the present paper, researc...Synthetic hexaploid wheat （Triticum turgidum x Aegilops tauschii） was created to explore for novel genes from T. turgidum and Ae. tauschii that can be used for common wheat improvement. In the present paper, research advances on the utilization of synthetic hexaploid wheat for wheat genetic improvement in China are reviewed. Over 200 synthetic hexaploid wheat （SHW） accessions from the International Maize and Wheat Improvement Centre （CIMMYT） were introduced into China since 1995. Four cultivars derived from these, Chuanmai 38, Chuanmai 42, Chuanmai 43 and Chuanmai 47, have been released in China. Of these, Chuanmai 42, with large kernels and resistance to stripe rust, had the highest average yield （〉 6 t/ha） among all cultivars over two years in Sichuan provincial yield trials, outyielding the commercial check cultivar Chuanmai 107 by 22,7%. Meanwhile, by either artificial chromosome doubling via colchicine treatment or spontaneous chromosome doubling via a union of unreduced gametes （2n） from T. turgidum-Ae, tauschii hybrids, new SHW lines were produced in China. Mitotic-like meiosis might be the cytological mechanism of spontaneous chromosome doubling. SHW lines with genes for spontaneous chromosome doubling may be useful for producing new SHW-alien amphidiploids and double haploid in wheat genetic improvement.展开更多
Aging is characterized by a progressive deterioration of physiological integrity,leading to impaired functional ability and ultimately increased susceptibility to death.It is a major risk factor for chronic human dise...Aging is characterized by a progressive deterioration of physiological integrity,leading to impaired functional ability and ultimately increased susceptibility to death.It is a major risk factor for chronic human diseases,including cardiovascular disease,diabetes,neurological degeneration,and cancer.Therefore,the growing emphasis on “healthy aging” raises a series of important questions in life and social sciences.In recent years,there has been unprecedented progress in aging research,particularly the discovery that the rate of aging is at least partly controlled by evolutionarily conserved genetic pathways and biological processes.In an attempt to bring full-fledged understanding to both the aging process and age-associated diseases,we review the descriptive,conceptual,and interventive aspects of the landscape of aging composed of a number of layers at the cellular,tissue,organ,organ system,and organismal levels.展开更多
Over 17 and 160 types of chemical modifications have been identified in DNA and RNA,respectively.The interest in understanding the various biological functions of DNA and RNA modifications has lead to the cutting-edge...Over 17 and 160 types of chemical modifications have been identified in DNA and RNA,respectively.The interest in understanding the various biological functions of DNA and RNA modifications has lead to the cutting-edged fields of epigenomics and epitranscriptomics.Developing chemical and biological tools to detect specific modifications in the genome or transcriptome has greatly facilitated their study.Here,we review the recent technological advances in this rapidly evolving field.We focus on high-throughput detection methods and biological findings for these modifications,and discuss questions to be addressed as well.We also summarize third-generation sequencing methods,which enable long-read and single-molecule sequencing of DNA and RNA modification.展开更多
According to the World Health Organization(WHO)newly updated situation report on March 18th,2020,the coronavirus disease 2019(COVID-19)pandemic has confirmed 191,127 cases and claimed 7807 deaths worldwide.1 The etiol...According to the World Health Organization(WHO)newly updated situation report on March 18th,2020,the coronavirus disease 2019(COVID-19)pandemic has confirmed 191,127 cases and claimed 7807 deaths worldwide.1 The etiological agent of COVID-19 has been identified as a novel coronavirus,the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),belonging to Sarbecovirus subgenus(genus Betacoronavirus,family Coronaviridae)and showing 79.6 and 96.2%sequence identity in nucleotide to SARS-CoV and a bat coronavirus(BatCoV RaTG13),respectively.2–4 Like SARS-CoV infection,a substantial fraction of COVID-19 patients exhibits severe respiratory symptoms and has to be hospitalized in intensive care unit.5–8 Although the mortality rate of COVID-19 is significantly lower than that of SARS-CoV infection,SARS-CoV-2 shows much higher human-to-human transmission rate,rapidly leading to a global pandemic declared by WHO on March 11th,2020.展开更多
User-friendly tools for robust transcriptional activation of endogenous genes are highly demanded in plants. We previously showed that a dCas9-VP64 system consisting of the deactivated CRISPR- associated protein 9 （d...User-friendly tools for robust transcriptional activation of endogenous genes are highly demanded in plants. We previously showed that a dCas9-VP64 system consisting of the deactivated CRISPR- associated protein 9 （dCasg） fused with four tandem repeats of the transcriptional activator VP16 0/1=64） could be used for transcriptional activation of endogenous genes in plants. In this study, we developed a second generation of vector systems for enhanced transcriptional activation in plants. We tested multiple strategies for dCasg-based transcriptional activation, and found that simultaneous recruitment of VP64 by dCas9 and a modified guide RNA scaffold gRNA2.0 （designated CRISPR-Act2.0） yielded stronger transcrip- tional activation than the dCas9-VP64 system. Moreover, we developed a multiplex transcription activator- likeeffector activation （mTALE-Act） system for simultaneous activation of up to four genes in plants. Our results suggest that mTALE-Act is even more effective than CRISPR-Act2.0 in most cases tested. In addition, we explored tissue-specific gene activation using positive feedback loops. Interestingly, our study revealed that certain endogenous genes are more amenable than others to transcriptional activation, and tightly regulated genes may cause target gene silencing when perturbed by activation probes. Hence, these new tools could be used to investigate gene regulatory networks and their control mechanisms. Assembly of multiplex CRISPR-Act2.0 and mTALE-Act systems are both based on streamlined and PCR-independent Golden Gate and Gateway cloning strategies, which will facilitate transcriptional activation applications in both dicots and monocots.展开更多
Aging biomarkers are a combination of biological parameters to(i)assess age-related changes,(ii)track the physiological aging process,and(iii)predict the transition into a pathological status.Although a broad spectrum...Aging biomarkers are a combination of biological parameters to(i)assess age-related changes,(ii)track the physiological aging process,and(iii)predict the transition into a pathological status.Although a broad spectrum of aging biomarkers has been developed,their potential uses and limitations remain poorly characterized.An immediate goal of biomarkers is to help us answer the following three fundamental questions in aging research:How old are we?Why do we get old?And how can we age slower?This review aims to address this need.Here,we summarize our current knowledge of biomarkers developed for cellular,organ,and organismal levels of aging,comprising six pillars:physiological characteristics,medical imaging,histological features,cellular alterations,molecular changes,and secretory factors.To fulfill all these requisites,we propose that aging biomarkers should qualify for being specific,systemic,and clinically relevant.展开更多
Zoige Wetland is one of the largest plateau wetlands in the world. This paper provides a dynamic analysis of spatial and temporal patterns of the wetland in Zoige, Eastern Qinghai-Tibetan Plateau, supported by ERDAS8....Zoige Wetland is one of the largest plateau wetlands in the world. This paper provides a dynamic analysis of spatial and temporal patterns of the wetland in Zoige, Eastern Qinghai-Tibetan Plateau, supported by ERDAS8.7 and ArcGIS9.0. It is the first comparative analysis of a system of rapidly changing wetland with landscape patterns in Zoige, using 3 classified landsat Thematic Mapper images of 1977, 1994 and 2001. The classified images were used to generate wetland distributing maps, and shape index （S）, diversity index （H）, dominance index （D）, evenness index （E）, fragmentation index （F） and fractal dimension （Fd） were calculated and analyzed spatiotemporally across pure grazing area in Zoige for each landscape type and in different periods （before 1977, during 1977-1994 and 1994-2001）, as well as the driving forces of natural and anthropogenic. The study shows that for a comprehensive understanding of the shapes and trajectories of the shrinking and desertificated land expansion of the wetland, a spatiotemporal landscape metrics analysis in different periods is an improvement than only with landscape changing rates. This type of analysis can also be used to infer underlying social, economic, and political processes that drive the observed wetland forms. The results indicate that wetland patterns can be changed over relatively short periods of time. The total area of lake reduced by 164.86 km^2, grassland extended by 141.74 km^2, semi-marsh extended by 105.94 km^2, marsh reduced by 86.00 km^2 the number of landscape patches reduced by 56, and their average area decreased by 2.68 km^2, the successions within lake, marsh, semi-marsh and grassland were found obviously. S decreased stepwise： D and F increased but H decreased： The changing rate after 1994 was 2.3 to 2.9 times greater than that before. The change of the wetland landscape patterns resulted in the interaction between socio-ceenomic and natural forces of positive and negative aspects; and natural factors affected as assi展开更多
CRISPR technologies enabling precise genome manipulation are valuable for gene function studies and molecular crop breeding. However, the requirement of a protospacer adjacent motif (PAM)y such as NGG and TTN, for Cas...CRISPR technologies enabling precise genome manipulation are valuable for gene function studies and molecular crop breeding. However, the requirement of a protospacer adjacent motif (PAM)y such as NGG and TTN, for Cas protein recognition restricts the selection of targetable genomic loci in practical applications of CRISPR technologies. Recently Cas9-NG, which recognizes a minimal NG PAM, was reported to expand the targeting space of genome editing in human cells, but it remains unclear whether this Cas9 variant can be used in plants. In this study, we evaluated the nuclease activity of Cas9-NG toward various NGN PAMs by targeting endogenous genes in transgenic rice. We found that Cas9-NG edits all NGG, NGA, NGT, and NGC sites with impaired activity, while the gene-edited plants were dominated by monoallelic mutations. Cas9-NG-engineered base editors were then developed and used to generate O s B Z R I gainof- function plants that can not be created by other available Cas9-engineered base editors. Moreover, we showed that a Cas9-NG-based transcriptional activator efficiently upregulated the expression of endogenous target genes in rice. In addition, we discovered that Cas9-NG recognizes NAC, NTG, NTT, and NCG apart from NG PAM. Together, these findings demonstrate that Cas9-NG can greatly expand the targeting scope of genome-editing tools, showing great potential for targeted genome editing, base editing, and genome regulation in plants.展开更多
The flavonoid compounds are important secondary metabolites with versatile human nutritive benefits and fulfill a multitude of functions during plant growth and development.The abundance of different flavonoid compoun...The flavonoid compounds are important secondary metabolites with versatile human nutritive benefits and fulfill a multitude of functions during plant growth and development.The abundance of different flavonoid compounds are finely tuned with species-specific pattern by a ternary MBW complex,which consists of a MYB,a bHLH,and a WD40 protein,but the essential role of SlAN11,which is a WD40 protein,is not fully understood in tomato until now.In this study,a tomato WD40 protein named as SlAN11 was characterized as an effective transcription regulator to promote plant anthocyanin and seed proanthocyanidin(PA)contents,with late flavonoid biosynthetic genes activated in 35S::SlAN11 transgenic lines,while the dihydroflavonol flow to the accumulation of flavonols or their glycosylated derivatives was reduced by repressing the expression of SlFLS in this SlAN11-overexpressed lines.The above changes were reversed in 35S::SlAN11-RNAi transgenic lines except remained levels of flavonol compounds and SlFLS expression.Interestingly,our data revealed that SlAN11 gene could affect seed dormancy by regulating the expressions of abscisic acid(ABA)signaling-related genes SlABI3 and SlABI5,and the sensitivity to ABA treatment in seed germination is conversely changed by SlAN11-overexpressed or-downregulated lines.Yeast two-hybrid assays demonstrated that SlAN11 interacted with bHLH but not with MYB proteins in the ternary MBW complex,whereas bHLH interacted with MYB in tomato.Our results indicated that low level of anthocyanins in tomato fruits,with low expression of bHLH(SlTT8)and MYB(SlANT1 and SlAN2)genes,remain unchanged upon modification of SlAN11 gene alone in the transgenic lines.These results suggest that the tomato WD40 protein SlAN11,coordinating with bHLH and MYB proteins,plays a crucial role in the fine adjustment of the flavonoid biosynthesis and seed dormancy in tomato.展开更多
Although the molecular basis of flowering time control is well dissected in the long day （LD） plant Arabidopsis, it is still largely unknown in the short day （SD） plant rice. Rice flowering time （heading date） i...Although the molecular basis of flowering time control is well dissected in the long day （LD） plant Arabidopsis, it is still largely unknown in the short day （SD） plant rice. Rice flowering time （heading date） is an important agronomic trait for season adaption and grain yield, which is affected by both genetic and environmental factors. During the last decade, as the nature of florigen was identified, notable progress has been made on exploration how florigen gene ,expression is genetically controlled. In Arabidopsis expression of certain key flowering integrators such as FLOWERING LOCUS C （FLC） and FLOWERING LOCUS T （FT） are also epige- netically regulated by various chromatin modifications, however, very little is known in rice on this aspect until very recently. This review summarized the advances of both genetic networks and chromatin modifications in rice flowering time control, attempting to give a complete view of the genetic and epigenetic architecture in complex network of rice flowering pathways.展开更多
Although snow cover plays an important role in structuring plant diversity in the alpine zone, there are few studies on the relationship between snow cover and species diversity of alpine meadows on the eastern Qingha...Although snow cover plays an important role in structuring plant diversity in the alpine zone, there are few studies on the relationship between snow cover and species diversity of alpine meadows on the eastern Qinghai-Tibetan Plateau. To assess the effect of snow cover on plant species diversity of alpine meadows, we used ten parallel transects of 60 m × 1 m for this study and described the changes in species diversity and composition associated with snow depth. With the division of snow depth into six classes, the highest species richness （S） and species diversity （H′） occurred with an intermediate snow depth, i.e., class Ⅲ and class Ⅳ, showing a unimodal curve with the increase in snow depth. The relationship between snow depth and plant diversity （both richness and Shannon index） could be depicted by quadratic equations. There was no evident relationship between diversity （both S and H′） and soil water content, which implied that other more important factors influenced species diversity. The patterns of diversity found in our study were largely attributed to freeze-thaw alteration, length of growing season and disturbances of livestock grazing. Furthermore, snow depth affected species composition, as evaluated by the Sorensen＇s index of similarity. In addition, almost all species limited to one snow depth class were found only in class Ⅲand class Ⅳ, indicating that intermediate snow depth was suitable for the survival and growth of many alpine species.展开更多
Vegetation maps are important sources of information for biodiversity conservation,ecological studies,vegetation management and restoration,and national strategic decision making.The current Vegetation Map of China(1:...Vegetation maps are important sources of information for biodiversity conservation,ecological studies,vegetation management and restoration,and national strategic decision making.The current Vegetation Map of China(1:1000000)was generated by a team of more than 250 scientists in an effort that lasted over 20 years starting in the 1980s.However,the vegetation distribution of China has experienced drastic changes during the rapid development of China in the last three decades,and it urgently needs to be updated to better represent the distribution of current vegetation types.Here,we describe the process of updating the Vegetation Map of China(1:1000000)generated in the 1980s using a‘‘crowdsourcing-change detection-classification-expert knowledge"vegetation mapping strategy.A total of 203,024 field samples were collected,and 50 taxonomists were involved in the updating process.The resulting updated map has 12 vegetation type groups,55 vegetation types/subtypes,and 866 vegetation formation/sub-formation types.The overall accuracy and kappa coefficient of the updated map are 64.8%and 0.52 at the vegetation type group level,61%and 0.55 at the vegetation type/subtype level and 40%and 0.38 at the vegetation formation/sub-formation level.When compared to the original map,the updated map showed that 3.3 million km^2 of vegetated areas of China have changed their vegetation type group during the past three decades due to anthropogenic activities and climatic change.We expect this updated map to benefit the understanding and management of China’s terrestrial ecosystems.展开更多
Tomato(Solanum lycopersicum)is a major horticultural crop worldwide and has emerged as a preeminent model for metabolic research.Although many research efforts have focused on the analysis of metabolite differences be...Tomato(Solanum lycopersicum)is a major horticultural crop worldwide and has emerged as a preeminent model for metabolic research.Although many research efforts have focused on the analysis of metabolite differences between varieties and species,the dynamics of metabolic changes during the tomato growth cycle and the regulatory networks that underlie these changes are poorly understood.In this study,we integrated high-resolution spatio-temporal metabolome and transcriptome data to systematically explore the metabolic landscape across 20 major tomato tissues and growth stages.In the resulting MicroTom Metabolic Network,the 540 detected metabolites and their co-expressed genes could be divided into 10 distinct clusters based on their biological functions.Using this dataset,we constructed a global map of the major metabolic changes that occur throughout the tomato growth cycle and dissected the underlying regulatory network.In addition to verifying previously well-established regulatory networks for important metabolites,we identified novel transcription factors that regulate the biosynthesis of important secondary metabolites such as steroidal glycoalkaloids and flavonoids.Our findings provide insights into spatiotemporal changes in tomato metabolism and generate a valuable resource for the study of metabolic regulatory processes in model plants.展开更多
Stenting is currently the major therapeutic treatment for cardiovascular diseases.However,the nonbiogenic metal stents are inclined to trigger a cascade of cellular and molecular events including inflammatory response...Stenting is currently the major therapeutic treatment for cardiovascular diseases.However,the nonbiogenic metal stents are inclined to trigger a cascade of cellular and molecular events including inflammatory response,thrombogenic reactions,smooth muscle cell hyperproliferation accompanied by the delayed arterial healing,and poor reendothelialization,thus leading to restenosis along with late stent thrombosis.To address prevalence critical problems,we present an endothelium-mimicking coating capable of rapid regeneration of a competently functioning new endothelial layer on stents through a stepwise metal(copper)-catechol-(amine)(MCA)surface chemistry strategy,leading to combinatorial endothelium-like functions with glutathione peroxidase-like catalytic activity and surface heparinization.Apart from the stable nitric oxide(NO)generating rate at the physiological level(2:2×10^(-10) mol/cm^(2)/min lasting for 60 days),this proposed strategy could also generate abundant amine groups for allowing a high heparin conjugation efficacy up to∼1μg/cm^(2),which is considerably higher than most of the conventional heparinized surfaces.The resultant coating could create an ideal microenvironment for bringing in enhanced antithrombogenicity,anti-inflammation,anti-proliferation of smooth muscle cells,re-endothelialization by regulating relevant gene expressions,hence preventing restenosis in vivo.We envision that the stepwise MCA coating strategy would facilitate the surface endothelium-mimicking engineering of vascular stents and be therefore helpful in the clinic to reduce complications associated with stenosis.展开更多
Herpes simplex virus （HSV）, a member of the Herpesviridae family, is a significant human pathogen that results in mucocutaneous lesions in the oral cavity or genital infections. Acyclovir （ACV） and related nucleos...Herpes simplex virus （HSV）, a member of the Herpesviridae family, is a significant human pathogen that results in mucocutaneous lesions in the oral cavity or genital infections. Acyclovir （ACV） and related nucleoside analogues can successfully treat HSV infections, but the emergence of drug resistance to ACV has created a barrier for the treatment of HSV infections, especially in immunocompromised patients. There is an urgent need to explore new and effective tactics to circumvent drug resistance to HSV. This review summarises the current strategies in the development of new targets （the DNA helicase/primase （H/P） complex）, new types of molecules （nature products） and new antiviral mechanisms （lethal mutagenesis of Janus-type nucleosides） to fight the drug resistance of HSV.展开更多
基金the National Natural Science Foundation of China (Nos. 30471378, 90202010 and 30211130504),and the Program of 100 Distinguished Young Scientists of the Chinese Academy of Sciences.
文摘Litter production, components and dynamics were investigated and forest floor litter was quantified throughout awhole year in three subalpine forests, dominated by tree species of spruce (SF), fir (FF) and birch (BF), in WesternSichuan, China, in order to understand the key factors that influenced litter production and dynamics. Litterfall in thethree forests consisted mainly of leaves, woody litter, reproductive organs and moss. Contribution of leaf litter to thetotal litterfall was significantly (P < 0.05) greater than that of woody litter, reproductive organs or moss. Regardlessof the stands, litterfall exhibited a marked monthly variation with the maximum litterfall peaks occurring in October,with smaller peaks occurring in February for SF and FF, and May for BF. The analysis indicated that tree species,stand density, leaf area index (LAI), stand basal area and stand age were the key factors determining litter production.Meanwhile tree species and phenology controlled the litter dynamics, with wind and snow modifying the litter componentsand dynamics.
基金Project supported by the National Natural Science Foundation of China (Nos. 30471378, 90202010 and 30211130504)the Applied and Basic Research Program of Sichuan Province, and the Talent-Recruiting Program of Sichuan Agricultural University
文摘Macronutrients （N, P, K, Ca, Mg, and S） in litter of three primarily spruce （Picea purpurea Masters） （SF）, fir （Abies faxoniana Rehder ＆ E. H. Wilson） （FF）, and birch （Betula platyphylla Sukaczev） （BF） subalpine forests in western China were measured to understand the monthly variations in litter nutrient concentrations and annual and monthly nutrient returns via litteffall. Nutrient concentration in litter showed the rank order of Ca 〉 N 〉 Mg 〉 K 〉 S 〉 P. Monthly variations in nutrient concentrations were greater in leaf litter （LL） than other litter components. The highest and lowest concentrations of N, P, K, and S in LL were found in the growing season and the nongrowing season, respectively, but Ca and Mg were the opposite. Nutrient returns via litterfall showed a marked monthly pattern with a major peak in October and one or two small peaks in February and/or May, varying with the element and stand type, but no marked monthly variations in nutrient returns via woody litter, reproductive litter, except in May for the BF, and moss litter. Not only litter production but also nutrient concentration controlled the annual nutrient return and the monthly nutrient return pattern. The monthly patterns of the nutrient concentration and return were of ecological importance for nutrient cycling and plant growth in the subalpine forest ecosystems.
基金the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0405)the Science and Technology Service Network Initiative(KFJ-STS-QYZD060)+3 种基金the State Key Research Development Program of China(2016YFC0501802,2016YFC0501803 and 2016YFC0502002)the National Natural Science Foundation of China(41871040 and 41501057)the Innovative Research Team of the Ministry of Education of China(IRT_17R59)the Fundamental Research Funds for the Central Universities。
文摘Grazing exclusion using fences is a key policy being applied by the Chinese government to rehabilitate degraded grasslands on the Tibetan Plateau(TP)and elsewhere.However,there is a limited understanding of the effects of grazing exclusion on alpine ecosystem functions and services and its impacts on herders’livelihoods.Our meta-analyses and questionnaire-based surveys revealed that grazing exclusion with fences was effective in promoting aboveground vegetation growth for up to four years in degraded alpine meadows and for up to eight years in the alpine steppes of the TP.Longer-term fencing did not bring any ecological and economic benefits.We also found that fencing hindered wildlife movement,increased grazing pressure in unfenced areas,lowered the satisfaction of herders,and rendered substantial financial costs to both regional and national governments.We recommend that traditional free grazing should be encouraged if applicable,short-term fencing(for 4-8 years)should be adopted in severely degraded grasslands,and fencing should be avoided in key wildlife habitat areas,especially the protected large mammal species.
基金This research was supported by the National Natural Science Foundation of China(No.81670895 and 81970839 to L.H.,81700841 to J.L.)the Department of Science and Technology of Sichuan Province,China(No.21ZDYF0551 to L.H2016FZ0091 to Ling Wan).
文摘Age-related macular degeneration (AMD) is a complex eye disorder and is the leading cause of incurable blindness worldwide in the elderly. Clinically, AMD initially affects the central area of retina known as the macula and it is classified as early stage to late stage (advanced AMD). The advanced AMD is classified into the nonexudative or atrophic form (dry AMD) and the exudative or neovascular form (wet AMD). More severe vision loss is typically associated with the wet form. Multiple genetic factors, lipid metabolism, oxidative stress and aging, play a role in the etiology of AMD. Dysregulation in genetic to AMD is established to 46%–71% of disease contribution, with CFH and ARMS2/HTRA1 to be the two most notable risk loci among the 103 identified AMD associated loci so far. Chronic cigarette smoking is the most proven consistently risk living habits for AMD. Deep learning algorithm has been developed based on image recognition to distinguish wet AMD and normal macula with high accuracy. Currently, anti-vascular endothelial growth factor (VEGF) therapy is highly effective at treating wet AMD. Several new generation AMD drugs and iPSC-derived RPE cell therapy are in the clinical trial stage and are promising to improve AMD treatment in the near future.
基金supported by grants from the Emergency Prevention and Control of COVID-19 Project of Henan Province(grant no.201100310900)the 2020 Science and Technology Project of Henan Province(grant no.202102310039)+1 种基金the National Natural Science Foundation of China(grant nos.91942314,U1804281,81602024)the State’s Key Project of Research and Development Plan(grant nos.2018YFC1313400,2016YFC1303500)。
文摘The recent novel coronavirus disease(COVID-19)outbreak,caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is seeing a rapid increase in infected patients worldwide.The host immune response to SARS-CoV-2 appears to play a critical role in disease pathogenesis and clinical manifestations.SARS-CoV-2 not only activates antiviral immune responses,but can also cause uncontrolled inflammatory responses characterized by marked pro-inflammatory cytokine release in patients with severe COVID-19,leading to lymphopenia,lymphocyte dysfunction,and granulocyte and monocyte abnormalities.These SARS-CoV-2-induced immune abnormalities may lead to infections by microorganisms,septic shock,and severe multiple organ dysfunction.Therefore,mechanisms underlying immune abnormalities in patients with COVID-19 must be elucidated to guide clinical management of the disease.Moreover,rational management of the immune responses to SARSCoV-2,which includes enhancing anti-viral immunity while inhibiting systemic inflammation,may be key to successful treatment.In this review,we discuss the immunopathology of COVID-19,its potential mechanisms,and clinical implications to aid the development of new therapeutic strategies against COVID-19.
基金supported by the National 863 pro-gram (No. 2006AA10Z1C6)the National Natural Science Foundation of China (No. 30771338 and 30700495)+1 种基金"100-Talent Program" of Chinese Academy of Sciencesthe Science and Technology Department of Sichuan Province
文摘Synthetic hexaploid wheat （Triticum turgidum x Aegilops tauschii） was created to explore for novel genes from T. turgidum and Ae. tauschii that can be used for common wheat improvement. In the present paper, research advances on the utilization of synthetic hexaploid wheat for wheat genetic improvement in China are reviewed. Over 200 synthetic hexaploid wheat （SHW） accessions from the International Maize and Wheat Improvement Centre （CIMMYT） were introduced into China since 1995. Four cultivars derived from these, Chuanmai 38, Chuanmai 42, Chuanmai 43 and Chuanmai 47, have been released in China. Of these, Chuanmai 42, with large kernels and resistance to stripe rust, had the highest average yield （〉 6 t/ha） among all cultivars over two years in Sichuan provincial yield trials, outyielding the commercial check cultivar Chuanmai 107 by 22,7%. Meanwhile, by either artificial chromosome doubling via colchicine treatment or spontaneous chromosome doubling via a union of unreduced gametes （2n） from T. turgidum-Ae, tauschii hybrids, new SHW lines were produced in China. Mitotic-like meiosis might be the cytological mechanism of spontaneous chromosome doubling. SHW lines with genes for spontaneous chromosome doubling may be useful for producing new SHW-alien amphidiploids and double haploid in wheat genetic improvement.
基金supported by the National Natural Science Foundation of China(31871380,32000500,32070730,32170756,32170804,81330008,81671377,81725010,81725010,81872874,81921006,81922027,81971312,81991512,82030041,82103167,82122024,82125009,82125011,82130044,91749126,91949101,91949207,92049302)the National Key Research and Development Program of China(2017YFA0506400,2018YFA0800200,2018YFA0800700,2018YFA0900200,2018YFC2000100,2018YFC2000400,2018YFE-0203700,20192ACB70002,2019YFA0802202,2020YFA0113400,2020YFA0803401,2020YFA0804000,2020YFC2002800,2020YFC-2002900,2021ZD0202401)+11 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16010100,XDA16010603,XDA16020400,XDB29020000,XDB39000000,XDB39000000,XDB39030300)the China Association for Science and Technology(2021QNRC001)the Beijing Municipal Science and Technology Commission(Z200022)the Natural Science Foundation of Shanghai(21JC1406400)the Key Programs of the Jiangxi ProvinceChina(20192ACB70002)the“Shu Guang”Project supported by the Shanghai Municipal Education Commission and Shanghai Education Development Foundation(19SG18)the Shanghai Sailing Program(22YF1434300)the Research Project of Joint Laboratory of University of Science and Technology of China and Anhui Mental Health Center(2019LH03)the Fundamental Research Funds for the Central Universities(WK2070210004)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(YESS20210002)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2022083)。
文摘Aging is characterized by a progressive deterioration of physiological integrity,leading to impaired functional ability and ultimately increased susceptibility to death.It is a major risk factor for chronic human diseases,including cardiovascular disease,diabetes,neurological degeneration,and cancer.Therefore,the growing emphasis on “healthy aging” raises a series of important questions in life and social sciences.In recent years,there has been unprecedented progress in aging research,particularly the discovery that the rate of aging is at least partly controlled by evolutionarily conserved genetic pathways and biological processes.In an attempt to bring full-fledged understanding to both the aging process and age-associated diseases,we review the descriptive,conceptual,and interventive aspects of the landscape of aging composed of a number of layers at the cellular,tissue,organ,organ system,and organismal levels.
基金This work was supported by the National Natural Science Foundation of China(Grant No.31861143026 to C.Y.)the Ministry of Science and Technology of China(Grant Nos.2019YFA0110902 and 2019YFA08002501 to C.Y.)the Ludwig Institute for Cancer Research(C-X.S.),Cancer Research UK(C63763/A26394 and C63763/A27122 to C-X.S.)NIHR Oxford Biomedical Research Centre(to C-X.S.)and Emerson Collective(to C-X.S.).L-Y.Z.is supported by China Scholarship Council.The views expressed are those of the authors and not necessarily those of the NHS,the NIHR or the Department of Health.We apologize for not being able to cite all the publications related to this topic due to space constraints of the journal.
文摘Over 17 and 160 types of chemical modifications have been identified in DNA and RNA,respectively.The interest in understanding the various biological functions of DNA and RNA modifications has lead to the cutting-edged fields of epigenomics and epitranscriptomics.Developing chemical and biological tools to detect specific modifications in the genome or transcriptome has greatly facilitated their study.Here,we review the recent technological advances in this rapidly evolving field.We focus on high-throughput detection methods and biological findings for these modifications,and discuss questions to be addressed as well.We also summarize third-generation sequencing methods,which enable long-read and single-molecule sequencing of DNA and RNA modification.
基金supported by grants from the National Natural Science Fund for Distinguished Young Scholars(No.31825011 to L.Y.)the Chongqing Special Research Project for Novel Coronavirus Pneumonia Prevention and Control(No.cstc2020jscx-2 to L.Y.,No.cstc2020jscx-fyzx0074 to Y.C.,cstc2020jscx-fyzx0135 to Y.C.).
文摘According to the World Health Organization(WHO)newly updated situation report on March 18th,2020,the coronavirus disease 2019(COVID-19)pandemic has confirmed 191,127 cases and claimed 7807 deaths worldwide.1 The etiological agent of COVID-19 has been identified as a novel coronavirus,the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),belonging to Sarbecovirus subgenus(genus Betacoronavirus,family Coronaviridae)and showing 79.6 and 96.2%sequence identity in nucleotide to SARS-CoV and a bat coronavirus(BatCoV RaTG13),respectively.2–4 Like SARS-CoV infection,a substantial fraction of COVID-19 patients exhibits severe respiratory symptoms and has to be hospitalized in intensive care unit.5–8 Although the mortality rate of COVID-19 is significantly lower than that of SARS-CoV infection,SARS-CoV-2 shows much higher human-to-human transmission rate,rapidly leading to a global pandemic declared by WHO on March 11th,2020.
基金This work was supported by startup funds from East Carolina University and University of Maryland-College Park and a Collaborative Funding grant from North Carolina Biotechnology Center and Syngenta Biotechnology （2016-CFG-8003） to Y.Q. This work was also supported by grants, including the Sichuan Youth Science and Technology Foundation （2017JQ0005）, the National Science Foundation of China （31771486）, and the Fundamental Research Funds for the Central Universities （ZYGX2016J119） to Y.Z.
文摘User-friendly tools for robust transcriptional activation of endogenous genes are highly demanded in plants. We previously showed that a dCas9-VP64 system consisting of the deactivated CRISPR- associated protein 9 （dCasg） fused with four tandem repeats of the transcriptional activator VP16 0/1=64） could be used for transcriptional activation of endogenous genes in plants. In this study, we developed a second generation of vector systems for enhanced transcriptional activation in plants. We tested multiple strategies for dCasg-based transcriptional activation, and found that simultaneous recruitment of VP64 by dCas9 and a modified guide RNA scaffold gRNA2.0 （designated CRISPR-Act2.0） yielded stronger transcrip- tional activation than the dCas9-VP64 system. Moreover, we developed a multiplex transcription activator- likeeffector activation （mTALE-Act） system for simultaneous activation of up to four genes in plants. Our results suggest that mTALE-Act is even more effective than CRISPR-Act2.0 in most cases tested. In addition, we explored tissue-specific gene activation using positive feedback loops. Interestingly, our study revealed that certain endogenous genes are more amenable than others to transcriptional activation, and tightly regulated genes may cause target gene silencing when perturbed by activation probes. Hence, these new tools could be used to investigate gene regulatory networks and their control mechanisms. Assembly of multiplex CRISPR-Act2.0 and mTALE-Act systems are both based on streamlined and PCR-independent Golden Gate and Gateway cloning strategies, which will facilitate transcriptional activation applications in both dicots and monocots.
基金supported by the National Natural Science Foundation of China(31730036,31871380,31871382,31930055,31930058,32000500,32022034,32030033,32070730,32130046,3217050247,32150005,32200595,32222024,81730019,81730022,81830014,81921006,81925005,81970426,81971301,81971312,82030041,82061160495,82070805,82071595,82090020,82100841,82120108009,82122024,82125002,82125011,82125012,82130045,82171284,82173061,82173398,82225007,82225015,82225017,82225018,82230047,82230088,82271600,91949106,91949201,92049116,92049302,92049304,92149303,92149306,92157202,92168201,92169102,92249301,92268201)the National Key Research and Development Program of China(2018YFA0800700,2018YFC2000100,2018YFC2000102,2018YFC2002003,2019YFA0110900,2019YFA0801703,2019YFA0801903,2019YFA0802202,2019YFA0904800,2020YFA0113400,2020YFA0803401,2020YFA0804000,2020YFC2002900,2020YFC2008000,2020YFE0202200,2021YFA0804900,2021YFA1100103,2021YFA1100900,2021YFE0114200,2021ZD0202400,2022YFA0806001,2022YFA0806002,2022YFA0806600,2022YFA1103200,2022YFA1103601,2022YFA1103701,2022YFA1103800,2022YFA1103801,2022YFA1104100,2022YFA1104904,2022YFA1303000,2022YFC2009900,2022YFC2502401,2022YFC3602400,2022YFE0118000,2022ZD0213200)+9 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16030302,XDB39000000,XDB39030600)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2020085,2021080)CAS Project for Young Scientists in Basic Research(YSBR-076)the Program of the Beijing Natural Science Foundation(JQ20031)Clinical Research Operating Fund of Central High level hospitals(2022-PUMCHE-001)CAMS Innovation Fund for Medical Sciences(CIFMS)(2022-I2M1-004)Talent Program of the Chinese Academy of Medical Science(2022RC310-10)Research Funds from Health@Inno HK Program launched by Innovation Technology Commission of the Hong Kong Special Administrative Region,Guangdong Basic and Applied Basic Research Foundation(2020B1515020044)Guangzhou Planned Project of Science and Technology(202002020039)the Major Technology Innovation of Hubei Province(2019ACA14
文摘Aging biomarkers are a combination of biological parameters to(i)assess age-related changes,(ii)track the physiological aging process,and(iii)predict the transition into a pathological status.Although a broad spectrum of aging biomarkers has been developed,their potential uses and limitations remain poorly characterized.An immediate goal of biomarkers is to help us answer the following three fundamental questions in aging research:How old are we?Why do we get old?And how can we age slower?This review aims to address this need.Here,we summarize our current knowledge of biomarkers developed for cellular,organ,and organismal levels of aging,comprising six pillars:physiological characteristics,medical imaging,histological features,cellular alterations,molecular changes,and secretory factors.To fulfill all these requisites,we propose that aging biomarkers should qualify for being specific,systemic,and clinically relevant.
基金supported by China Scholarship, the Chinese Academy of Sciences (KSCXI-07, KSCX2-01-09)the Ministry of Science & Technology of China (2004BA606A-05)Sichuan provincial training foundation for Science & Technology leader ,Sichuan youth foundation.
文摘Zoige Wetland is one of the largest plateau wetlands in the world. This paper provides a dynamic analysis of spatial and temporal patterns of the wetland in Zoige, Eastern Qinghai-Tibetan Plateau, supported by ERDAS8.7 and ArcGIS9.0. It is the first comparative analysis of a system of rapidly changing wetland with landscape patterns in Zoige, using 3 classified landsat Thematic Mapper images of 1977, 1994 and 2001. The classified images were used to generate wetland distributing maps, and shape index （S）, diversity index （H）, dominance index （D）, evenness index （E）, fragmentation index （F） and fractal dimension （Fd） were calculated and analyzed spatiotemporally across pure grazing area in Zoige for each landscape type and in different periods （before 1977, during 1977-1994 and 1994-2001）, as well as the driving forces of natural and anthropogenic. The study shows that for a comprehensive understanding of the shapes and trajectories of the shrinking and desertificated land expansion of the wetland, a spatiotemporal landscape metrics analysis in different periods is an improvement than only with landscape changing rates. This type of analysis can also be used to infer underlying social, economic, and political processes that drive the observed wetland forms. The results indicate that wetland patterns can be changed over relatively short periods of time. The total area of lake reduced by 164.86 km^2, grassland extended by 141.74 km^2, semi-marsh extended by 105.94 km^2, marsh reduced by 86.00 km^2 the number of landscape patches reduced by 56, and their average area decreased by 2.68 km^2, the successions within lake, marsh, semi-marsh and grassland were found obviously. S decreased stepwise： D and F increased but H decreased： The changing rate after 1994 was 2.3 to 2.9 times greater than that before. The change of the wetland landscape patterns resulted in the interaction between socio-ceenomic and natural forces of positive and negative aspects; and natural factors affected as assi
基金National Natural Science Foundation of China (31871948)the National Key Research and Development Program of China (2017YFD0200900)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences to H.Z.
文摘CRISPR technologies enabling precise genome manipulation are valuable for gene function studies and molecular crop breeding. However, the requirement of a protospacer adjacent motif (PAM)y such as NGG and TTN, for Cas protein recognition restricts the selection of targetable genomic loci in practical applications of CRISPR technologies. Recently Cas9-NG, which recognizes a minimal NG PAM, was reported to expand the targeting space of genome editing in human cells, but it remains unclear whether this Cas9 variant can be used in plants. In this study, we evaluated the nuclease activity of Cas9-NG toward various NGN PAMs by targeting endogenous genes in transgenic rice. We found that Cas9-NG edits all NGG, NGA, NGT, and NGC sites with impaired activity, while the gene-edited plants were dominated by monoallelic mutations. Cas9-NG-engineered base editors were then developed and used to generate O s B Z R I gainof- function plants that can not be created by other available Cas9-engineered base editors. Moreover, we showed that a Cas9-NG-based transcriptional activator efficiently upregulated the expression of endogenous target genes in rice. In addition, we discovered that Cas9-NG recognizes NAC, NTG, NTT, and NCG apart from NG PAM. Together, these findings demonstrate that Cas9-NG can greatly expand the targeting scope of genome-editing tools, showing great potential for targeted genome editing, base editing, and genome regulation in plants.
基金The research was supported by the National Natural Science Foundation of China(No.31500205,No.31770644,and No.81703656)Scientific Research Fund of Sichuan Provincial Education Department(No.17ZB0456 and No.13TD0023)+2 种基金Yunnan Engineering Laboratory for Agro-environment Pollution Control and Eco-remediation/The Innovation Team for Farmland Non-pollution Production of Yunnan Province(No.2017HC015)the doctoral Fund Project(No.14zx7157 and No.13zx7116)Longshan academic talent research supporting program(No.17LZXT09)of Southwest University of Science and Technology.
文摘The flavonoid compounds are important secondary metabolites with versatile human nutritive benefits and fulfill a multitude of functions during plant growth and development.The abundance of different flavonoid compounds are finely tuned with species-specific pattern by a ternary MBW complex,which consists of a MYB,a bHLH,and a WD40 protein,but the essential role of SlAN11,which is a WD40 protein,is not fully understood in tomato until now.In this study,a tomato WD40 protein named as SlAN11 was characterized as an effective transcription regulator to promote plant anthocyanin and seed proanthocyanidin(PA)contents,with late flavonoid biosynthetic genes activated in 35S::SlAN11 transgenic lines,while the dihydroflavonol flow to the accumulation of flavonols or their glycosylated derivatives was reduced by repressing the expression of SlFLS in this SlAN11-overexpressed lines.The above changes were reversed in 35S::SlAN11-RNAi transgenic lines except remained levels of flavonol compounds and SlFLS expression.Interestingly,our data revealed that SlAN11 gene could affect seed dormancy by regulating the expressions of abscisic acid(ABA)signaling-related genes SlABI3 and SlABI5,and the sensitivity to ABA treatment in seed germination is conversely changed by SlAN11-overexpressed or-downregulated lines.Yeast two-hybrid assays demonstrated that SlAN11 interacted with bHLH but not with MYB proteins in the ternary MBW complex,whereas bHLH interacted with MYB in tomato.Our results indicated that low level of anthocyanins in tomato fruits,with low expression of bHLH(SlTT8)and MYB(SlANT1 and SlAN2)genes,remain unchanged upon modification of SlAN11 gene alone in the transgenic lines.These results suggest that the tomato WD40 protein SlAN11,coordinating with bHLH and MYB proteins,plays a crucial role in the fine adjustment of the flavonoid biosynthesis and seed dormancy in tomato.
基金This study was financially supported by the National Natural Science Foundation of China （Grant Nos. 31371602 and 91335107） and Specialized Research Fund for the Doctoral Program of Higher Education （20125103120008）.
文摘Although the molecular basis of flowering time control is well dissected in the long day （LD） plant Arabidopsis, it is still largely unknown in the short day （SD） plant rice. Rice flowering time （heading date） is an important agronomic trait for season adaption and grain yield, which is affected by both genetic and environmental factors. During the last decade, as the nature of florigen was identified, notable progress has been made on exploration how florigen gene ,expression is genetically controlled. In Arabidopsis expression of certain key flowering integrators such as FLOWERING LOCUS C （FLC） and FLOWERING LOCUS T （FT） are also epige- netically regulated by various chromatin modifications, however, very little is known in rice on this aspect until very recently. This review summarized the advances of both genetic networks and chromatin modifications in rice flowering time control, attempting to give a complete view of the genetic and epigenetic architecture in complex network of rice flowering pathways.
基金supported by the National Natural Science Foundation of China (40671181, 30870396)the Chinese Academy of Sciences (KZCX2-YW-418, KZCX2-XB2-02)+1 种基金the Ministry of Science & Technology of China (2006BAC01A15, 2006BAC01A11)the Science & Technology Bureau of Sichuan, China (03ZQ026-043)
文摘Although snow cover plays an important role in structuring plant diversity in the alpine zone, there are few studies on the relationship between snow cover and species diversity of alpine meadows on the eastern Qinghai-Tibetan Plateau. To assess the effect of snow cover on plant species diversity of alpine meadows, we used ten parallel transects of 60 m × 1 m for this study and described the changes in species diversity and composition associated with snow depth. With the division of snow depth into six classes, the highest species richness （S） and species diversity （H′） occurred with an intermediate snow depth, i.e., class Ⅲ and class Ⅳ, showing a unimodal curve with the increase in snow depth. The relationship between snow depth and plant diversity （both richness and Shannon index） could be depicted by quadratic equations. There was no evident relationship between diversity （both S and H′） and soil water content, which implied that other more important factors influenced species diversity. The patterns of diversity found in our study were largely attributed to freeze-thaw alteration, length of growing season and disturbances of livestock grazing. Furthermore, snow depth affected species composition, as evaluated by the Sorensen＇s index of similarity. In addition, almost all species limited to one snow depth class were found only in class Ⅲand class Ⅳ, indicating that intermediate snow depth was suitable for the survival and growth of many alpine species.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA19050401)Maps in this article were reviewed by Ministry of Natural Resources of the People’s Republic of China(GS(2020)1044)。
文摘Vegetation maps are important sources of information for biodiversity conservation,ecological studies,vegetation management and restoration,and national strategic decision making.The current Vegetation Map of China(1:1000000)was generated by a team of more than 250 scientists in an effort that lasted over 20 years starting in the 1980s.However,the vegetation distribution of China has experienced drastic changes during the rapid development of China in the last three decades,and it urgently needs to be updated to better represent the distribution of current vegetation types.Here,we describe the process of updating the Vegetation Map of China(1:1000000)generated in the 1980s using a‘‘crowdsourcing-change detection-classification-expert knowledge"vegetation mapping strategy.A total of 203,024 field samples were collected,and 50 taxonomists were involved in the updating process.The resulting updated map has 12 vegetation type groups,55 vegetation types/subtypes,and 866 vegetation formation/sub-formation types.The overall accuracy and kappa coefficient of the updated map are 64.8%and 0.52 at the vegetation type group level,61%and 0.55 at the vegetation type/subtype level and 40%and 0.38 at the vegetation formation/sub-formation level.When compared to the original map,the updated map showed that 3.3 million km^2 of vegetated areas of China have changed their vegetation type group during the past three decades due to anthropogenic activities and climatic change.We expect this updated map to benefit the understanding and management of China’s terrestrial ecosystems.
基金This study was funded by grants from the National Natural Science Foundation of China(31701255,31772372,and 31670352)Y.Z.was supported by the Fundamental Research Funds for the Central Universities(2017SCU04A11 and SCU2019D013)+1 种基金M.L.acknowledges support from the National Key R&D Program of China(2016YFD0400100)S.A.and A.R.F.acknowledge support from the PlantaSYST project of the European Union’s Horizon 2020 research and innovation program(SGA-CSA no.664621 and no.739582 under FPA no.664620).
文摘Tomato(Solanum lycopersicum)is a major horticultural crop worldwide and has emerged as a preeminent model for metabolic research.Although many research efforts have focused on the analysis of metabolite differences between varieties and species,the dynamics of metabolic changes during the tomato growth cycle and the regulatory networks that underlie these changes are poorly understood.In this study,we integrated high-resolution spatio-temporal metabolome and transcriptome data to systematically explore the metabolic landscape across 20 major tomato tissues and growth stages.In the resulting MicroTom Metabolic Network,the 540 detected metabolites and their co-expressed genes could be divided into 10 distinct clusters based on their biological functions.Using this dataset,we constructed a global map of the major metabolic changes that occur throughout the tomato growth cycle and dissected the underlying regulatory network.In addition to verifying previously well-established regulatory networks for important metabolites,we identified novel transcription factors that regulate the biosynthesis of important secondary metabolites such as steroidal glycoalkaloids and flavonoids.Our findings provide insights into spatiotemporal changes in tomato metabolism and generate a valuable resource for the study of metabolic regulatory processes in model plants.
基金This work was supported by the National Natural Science Foundation of China(31570957)International Cooperation Project by the Science and Technology Department of Sichuan Province(2019YFH0103)+1 种基金Early Career Researcher Development Scheme 2017 of Institute of Health and Biomedical Innovation,Queensland University of Technology and International Team for Implantology Research Grant(1260_2017)Applied Basic Research Project funded by Sichuan Provincial Science and Technology Department(2017JY0296).
文摘Stenting is currently the major therapeutic treatment for cardiovascular diseases.However,the nonbiogenic metal stents are inclined to trigger a cascade of cellular and molecular events including inflammatory response,thrombogenic reactions,smooth muscle cell hyperproliferation accompanied by the delayed arterial healing,and poor reendothelialization,thus leading to restenosis along with late stent thrombosis.To address prevalence critical problems,we present an endothelium-mimicking coating capable of rapid regeneration of a competently functioning new endothelial layer on stents through a stepwise metal(copper)-catechol-(amine)(MCA)surface chemistry strategy,leading to combinatorial endothelium-like functions with glutathione peroxidase-like catalytic activity and surface heparinization.Apart from the stable nitric oxide(NO)generating rate at the physiological level(2:2×10^(-10) mol/cm^(2)/min lasting for 60 days),this proposed strategy could also generate abundant amine groups for allowing a high heparin conjugation efficacy up to∼1μg/cm^(2),which is considerably higher than most of the conventional heparinized surfaces.The resultant coating could create an ideal microenvironment for bringing in enhanced antithrombogenicity,anti-inflammation,anti-proliferation of smooth muscle cells,re-endothelialization by regulating relevant gene expressions,hence preventing restenosis in vivo.We envision that the stepwise MCA coating strategy would facilitate the surface endothelium-mimicking engineering of vascular stents and be therefore helpful in the clinic to reduce complications associated with stenosis.
基金the National Natural Science Foundations of China(document no.:81321002,81500860,81300888)a grant from 111 Project of Ministry of Education,China,for fi nancial support
文摘Herpes simplex virus （HSV）, a member of the Herpesviridae family, is a significant human pathogen that results in mucocutaneous lesions in the oral cavity or genital infections. Acyclovir （ACV） and related nucleoside analogues can successfully treat HSV infections, but the emergence of drug resistance to ACV has created a barrier for the treatment of HSV infections, especially in immunocompromised patients. There is an urgent need to explore new and effective tactics to circumvent drug resistance to HSV. This review summarises the current strategies in the development of new targets （the DNA helicase/primase （H/P） complex）, new types of molecules （nature products） and new antiviral mechanisms （lethal mutagenesis of Janus-type nucleosides） to fight the drug resistance of HSV.
