Charophytic algae and land plants together make up a monophyletic group, streptophytes, which represents one of the main lineages of multicellular eukaryotes and has contributed greatly to the change of the environmen...Charophytic algae and land plants together make up a monophyletic group, streptophytes, which represents one of the main lineages of multicellular eukaryotes and has contributed greatly to the change of the environment on earth in the Phanerozoic Eon. Significant progress has been made to understand phylogenetic relationships among members of this group by phylogenetic studies of morphological and molecular data over the last twenty-five years. Mesostigma viride is now regarded as among the earliest diverging unicellular organisms in streptophytes. Characeae are the sister group to land plants. Liverworts represent the first diverging lineage of land plants. Hornworts and lycophytes are extant representatives of bryophytes and vascular plants, respectively, when early land plants changed from gametophyte to sporophyte as the dominant generation in the life cycle. Equisetum, Psilotaceae, and ferns constitute the monophyletic group of monilophytes, which are sister to seed plants. Gnetales are related to conifers, not to angiosperms as previously thought. Amborella, Nymphaeales, Hydatellaceae, Illiciales, Trimeniaceae, and Austrobaileya represent the earliest diverging lineages of extant angiosperms. These phylogenetic results, together with recent progress on elucidating genetic and developmental aspects of the plant life cycle, multicellularity, and gravitropism, will facilitate evolutionary developmental studies of these key traits, which will help us to gain mechanistic understanding on how plants adapted to environmental challenges when they colonized the land during one of the major transitions in evolution of life.展开更多
In multicellular and even single-celled organisms,individual components are interconnected at multiscale levels to produce enormously complex biological networks that help these systems maintain homeostasis for develo...In multicellular and even single-celled organisms,individual components are interconnected at multiscale levels to produce enormously complex biological networks that help these systems maintain homeostasis for development and environmental adaptation.Systems biology studies initially adopted network analysis to explore how relationships between individual components give rise to complex biological processes.Network analysis has been applied to dissect the complex connectivity of mammalian brains across different scales in time and space in The Human Brain Project.In plant science,network analysis has similarly been applied to study the connectivity of plant components at the molecular,subcellular,cellular,organic,and organism levels.Analysis of these multiscale networks contributes to our understanding of how genotype determines phenotype.In this review,we summarized the theoretical framework of plant multiscale networks and introduced studies investigating plant networks by various experimental and computational modalities.We next discussed the currently available analytic methodologies and multi-level imaging techniques used to map multiscale networks in plants.Finally,we highlighted some of the technical challenges and key questions remaining to be addressed in this emerging field.展开更多
Due to tissue lineage variances and the anisotropic physiological character-istics,regenerating complex osteochondral tissues(cartilage and subchondral bone)remains a great challenge,which is primarily due to the dist...Due to tissue lineage variances and the anisotropic physiological character-istics,regenerating complex osteochondral tissues(cartilage and subchondral bone)remains a great challenge,which is primarily due to the distinct requirements for cartilage and subchondral bone regeneration.For cartilage regeneration,a significant amount of newly generated chondrocytes is required while maintaining their phenotype.Conversely,bone regeneration necessitates inducing stem cells to differentiate into osteoblasts.Additionally,the construction of the osteochondral interface is crucial.In this study,we fabricated a biphasic multicellular bioprinted scaffold mimicking natural osteochondral tissue employing three-dimensional(3D)bioprinting technol-ogy.Briefly,gelatin-methacryloyl(GelMA)loaded with articular chondrocytes and bone marrow mesenchymal stem cells(ACs/BMSCs),serving as the cartilage layer,preserved the phenotype of ACs and promoted the differentia-tion of BMSCs into chondrocytes through the interaction between ACs and BMSCs,thereby facilitating cartilage regeneration.GelMA/strontium-substituted xonotlite(Sr-CSH)loaded with BMSCs,serving as the subchondral bone layer,regulated the differentiation of BMSCs into osteoblasts and enhanced the secretion of cartilage matrix by ACs in the cartilage layer through the slow release of bioactive ions from Sr-CSH.Additionally,GelMA,serving as the matrix material,contributed to the reconstruction of the osteochondral interface.Ultimately,this biphasic multicellular bioprinted scaffold demonstrated satisfactory simultaneous regeneration of osteochondral defects.In this study,a promising strategy for the application of 3D bioprinting technology in complex tissue regeneration was proposed.展开更多
Macroalgae are multicellular,aquatic autotrophs that play vital roles in global climate maintenance and have diverse applications in biotechnology and eco-engineering,which are directly linked to their multicellularit...Macroalgae are multicellular,aquatic autotrophs that play vital roles in global climate maintenance and have diverse applications in biotechnology and eco-engineering,which are directly linked to their multicellularity phenotypes.However,their genomic diversity and the evolutionary mechanisms underlying multicellularity in these organisms remain uncharacterized.In this study,we sequenced 110 macroalgal genomes from diverse climates and phyla,and identified key genomic features that distinguish them from their microalgal relatives.Genes for cell adhesion,extracellular matrix formation,cell polarity,transport,and cell differentiation distinguish macroalgae from microalgae across all three major phyla,constituting conserved and unique gene sets supporting multicellular processes.Adhesome genes show phylum-and climate-specific expansions that may facilitate niche adaptation.Collectively,our study reveals genetic determinants of convergent and divergent evolutionary trajectories that have shaped morphological diversity in macroalgae and provides genome-wide frameworks to understand photosynthetic multicellular evolution in aquatic environments.展开更多
背景:组织工程骨构建体的血管化性能不足是限制骨组织工程用于修复大尺寸骨缺损临床应用的主要挑战。目的:对近年来利用骨形成细胞和血管生成细胞构建组织工程构建体(基于支架或无支架)在骨修复中的应用进行了概述,以期实现组织工程骨...背景:组织工程骨构建体的血管化性能不足是限制骨组织工程用于修复大尺寸骨缺损临床应用的主要挑战。目的:对近年来利用骨形成细胞和血管生成细胞构建组织工程构建体(基于支架或无支架)在骨修复中的应用进行了概述,以期实现组织工程骨可持续的血管生成及生成功能完善的血管,从而提高骨组织工程在大尺寸骨缺损修复应用中的细胞存活率、并为促进骨的形成和重塑提供参考。方法:应用计算机对中国知网、PubMed及Web of Science数据库2000-2021年发表的文献进行了检索,中文检索词为“骨组织工程、成骨成血管、多细胞”,英文检索词为“Bone Tissue Engineering,Osteogenesis and angiogenesis,Multicellular”,根据纳入和排除标准,最终纳入63篇文献进行结果分析。结果与结论:①目前最常用的骨形成细胞主要有间充质干细胞、脂肪干细胞和成骨细胞,常用的血管生成细胞有人脐静脉内皮细胞和内皮祖细胞。②支架内包封细胞在实现各类细胞的精准定位方面优于在支架上接种细胞。③将两种单一细胞膜片相叠加或者共培养单层细胞膜片相叠加的方法,可以调控各类细胞的位置,从而构建血管化网络。④目前,基于支架的组织工程技术还需克服支架降解速率与组织再生速率的不匹配性、细胞与生物材料相互作用不可控等问题,而基于无支架细胞膜片的组织工程还需要克服力学强度低的难题。⑤未来研究需构建具有临床所需大小的功能性3D血管化组织工程骨,还需关注包括细胞培养和生物学作用机制;结合组织工程、细胞工程和基因工程构建组织工程骨,有望实现刺激早期血管生成、保持血液循环,防止构建体内部的细胞死亡,并起到加速构建体修复临床大体积骨缺损的作用。展开更多
Escherichia coli RecA has been considered traditionally a cellular protein with multiple vital functions working to ensure the maintenance of integrity of genome in each individual bacterial cell as well as promoting ...Escherichia coli RecA has been considered traditionally a cellular protein with multiple vital functions working to ensure the maintenance of integrity of genome in each individual bacterial cell as well as promoting swarming migration in collectivity. On the contrary, recently it has been described that RecA promotes cellular apoptotic-like death (ALD), a pathway of programmed cellular death (PCD). In fact, RecA has been dubbed as the major apoptotic executor in E. coli. From these studies, RecA emerges as a prototypical Gin/Gan protein that despite of their intrinsic vital and lethal anfi-funcionality becomes in a WISE factor: a Worker to Integrate Survival and Evolution in E. coli evolving populations living in community. Here, I provide a review of recent experimental and conceptual advances trying to understand these RecA’s antagonistic roles in appearance contradictory under a unified biological vision.展开更多
Cilia and flagella are organelles of motility that enable cells to swim or move liquid over its surface. An exhaustive literature survey for the presence of the organelle in organisms across phyla showed that most ani...Cilia and flagella are organelles of motility that enable cells to swim or move liquid over its surface. An exhaustive literature survey for the presence of the organelle in organisms across phyla showed that most animal cells harbor cilia in contrast to very few fungal cells. While this was not unexpected, it was the position and arrangement of this organelle in each cell that intrigued our attention. Natural selection might have favored motility over chemotaxis;and it would have done so to evolve a stable structure that could have undergone an optimization process requiring a precise geometry in the shape of cells and the structure that would help cells to move. The positioning of such a structure would play a pre-dominant role in optimal motility. It is now known that the flagellar position of a cell is a genetically distinct trait, occasionally used in phylogeny of bacteria, distributed in distinguishing patterns over cellular surface, but basically are of two types, either polar (one flagellum arising from one pole per cell) or peritrichous (lateral flagella distributed over the entire cell surface). Irrespective of the cellular habitat, flagella origin, ultrastructure and proteome, the present investigation surveyed 26 sub-types of flagellar arrangements from as many species as possible. A peculiar pattern ensued-Prokaryotes harbored predominantly polar and peritrichous types;eukaryotes showed a mere change of the peritrichous one. These numbers when used to create a Similarity tree depicted a similarity distance of 14 between the Eubacteria and Archaebacteria forming the first neighborhood;Protozoans, Algae, Fungi, Plantae and Animalia formed a second neighborhood. We offer a working hypothesis for this pattern and the gradual shift in the flagellar arrangement from polar, peritrichous, sub-apical, and apical to lateral throughout evolution.展开更多
In 1997 and 1998, hundreds of specimens of megascopic carbonaceous compressions or algal fossils were found from - 1800-million-year old Changzhougou Formation, which is the lowermost unit of the latest Palaeoproteroz...In 1997 and 1998, hundreds of specimens of megascopic carbonaceous compressions or algal fossils were found from - 1800-million-year old Changzhougou Formation, which is the lowermost unit of the latest Palaeoproterozoic Changcheng Group (~1 600-1 800 Ma) in the Xinglong-Kuancheng areas at the middle Yanshan Range, North China. They are discoid, ellipsoid and sausage-like, namely shaped like Chuaria Shouhsiennia (Ellipsophyta) and Tawuia. By adopting HF acid-resistant maceration coupled with scanning electron microscope and petrologic section, the authors made a preliminary research on the histology for some circular and ellipsoid carbonaceous compressions, namely Chuaria- and Shouhsienia-llke forms, in addition to their morphology. The following three types of multicellular tissues have been found in the fragments of them: colony-like, pseudoparenchyma-like and parenchyma-like. All of the new data about multicelluar tissues not only supply a very important basis in histology to determine the展开更多
Plant trichomes serve as a highly suitable model for investigating cell differentiation at the single-cell level. The regulatory genes involved in unicellular trichome develop- ment in Arabidopsis thaliana have been i...Plant trichomes serve as a highly suitable model for investigating cell differentiation at the single-cell level. The regulatory genes involved in unicellular trichome develop- ment in Arabidopsis thaliana have been intensively studied, but genes regulating multicellular trichome development in plants remain unclear. Here, we characterized Cucumis sativus （cucumber） trichomes as representative multicellular and unbranched structures, and identified Micro-trichome （Mict）, using map-based cloning in an F2 segregating population of 7,936 individuals generated from a spontaneous mict mutant. In mitt plants, trichomes in both leaves and fruits, are small, poorly developed, and denser than in the wild type. Sequence analysis revealed that a 2,649-bp genomic deletion, spanning the first and second exons, occurred in a plant-specific class I homeodomain-leucine zipper gene. Tissue-specific expression analysis indicated that Mict is strongly expressed in the trichome cells. Transcriptome profiling identified potential targets of Mict including putative homologs of genes known in other systems to regulate trichome development, meristem determinacy, and hormone responsiveness. Phylo- genic analysis charted the relationships among putative homologs in angiosperms. Our paper represents initial steps toward understanding the development of multicellular trichomes.展开更多
Vegetative cells of Porphyra yezoensis are isolated with sea snail enzyme and cultured on the solidified agar medium. The results of experiments show that the isolated cells can survive,divide and regenerate well on t...Vegetative cells of Porphyra yezoensis are isolated with sea snail enzyme and cultured on the solidified agar medium. The results of experiments show that the isolated cells can survive,divide and regenerate well on the medium solidified with agar. The first division on the solid medium starts after 7 days' culture, 4 days later than the liquid culture. The survival rate of isolated cells is 71.3% on the solid medium, lower than the 86.2% of that in seawater.Thalli, thalloids,conchocelis, spermatangia and multicellular masses are developed on the solid/medium in the first month, slowly but normally. Spermatangia sacs disappear within 4 weeks. Without adding nutrient liquid onto the surface of solid medium or injecting seawater under the agar layer in order to keep moisture, the thalli and cell groups release monospores to form new thalli instead of enlarging their areas after 5 weeks' culturing. Some monospores regenerate new thalli. Other monospores lose their pigments and minimize their volume and divide quickly to form light pink calli. After 16 weeks, numerous calli can be seen on the solid medium and after 24 weeks' culturing, almost only calli and conchocelis can be seen. If the calli are immersed in seawater, the monospores are released and may develop into young thallus.展开更多
Until recently, ovarian cancer research has mainly focused on the tumor cells themselves ignoring for the most part the surrounding tumor environment which includes malignant peritoneal effusions. However, one of the ...Until recently, ovarian cancer research has mainly focused on the tumor cells themselves ignoring for the most part the surrounding tumor environment which includes malignant peritoneal effusions. However, one of the major conceptual advances in oncology over the last few years has been the appreciation that cancer progression cannot be explained by aberrations in cancer cells themselves and is strongly influenced by the surrounding tumor environment. The mechanisms of ovarian cancer progression differ from that of other solid tumors because ovarian cancer cells primarily disseminate within the peritoneal cavity.Malignant peritoneal effusion accumulates in the peritoneal cavity during ovarian cancer progression. These exudative fluids act as a unique tumor environment providing a framework that orchestrates cellular and molecular changes contributing to aggressiveness and disease progression. The composition of ascites, which includes cellular and acellular components, constantly adapts during the course of the disease in response to various cellular cues originating from both tumor and stromal cells. The tumor environment that represents peritoneal effusions closely constitute an ecosystem, with specific cell types and signaling molecules increasing and decreasing during the course of the disease progression creating a single complex network. Although recent advances aiming to understand the ovarian tumor environment have focused one at a time on components, the net impact of the whole environment cannot be understood simply from its parts or outside is environmental context.展开更多
Multicellular layers(MCLs) have previously been used to determine the pharmacokinetics of a variety of different cancer drugs including paclitaxel, doxorubicin, methotrexate, and 5-fluorouracil across a number of cell...Multicellular layers(MCLs) have previously been used to determine the pharmacokinetics of a variety of different cancer drugs including paclitaxel, doxorubicin, methotrexate, and 5-fluorouracil across a number of cell lines. It is not known how nanoparticles(NPs) navigate through the tumor microenvironment once they leave the tumor blood vessel.In this study, we used the MCL model to study the uptake and penetration dynamics of NPs. Gold nanoparticles(GNPs)were used as a model system to map the NP distribution within tissue-like structures. Our results show that NP uptake and transport are dependent on the tumor cell type. MDA-MB-231 tissue showed deeper penetration of GNPs as compared to MCF-7 one. Intracellular and extracellular distributions of NPs were mapped using Cyto Viva imaging. The ability of MCLs to mimic tumor tissue characteristics makes them a useful tool in assessing the efficacy of particle distribution in solid tumors.展开更多
The Lantian biota at the Lantian Town of Xiuning County, Anhui Province, is preserved in black shales of the Ediacaran Lantian Formation. It yields some of the oldest known complex macroorganisms, including fan-shaped...The Lantian biota at the Lantian Town of Xiuning County, Anhui Province, is preserved in black shales of the Ediacaran Lantian Formation. It yields some of the oldest known complex macroorganisms, including fan-shaped seaweeds and possible animal fossils with tentacles and intestinal-like structures reminiscent of modern coelenterates and bilaterians. The Lantian Lagerst^itte sheds new light on the origin and early evolution of multicellular organisms in relatively quiet and deep environments soon after the Neoproterozoic Marinoan glaciation. The morphological complexity and diversity of early multicellular organisms may be closely related to sexual reproduction and alternation of generations. The fluctuation of oceanic redox conditions during this peri- od may have played a role in the ecology and preservation of the Lantian biota.展开更多
Recapitulating the tumor microenvironment is a major challenge in the development of in vitro tumor model for the study of cancer biology and therapeutic treatments. 3D multicellular tumor spheroids (MCTS) have been u...Recapitulating the tumor microenvironment is a major challenge in the development of in vitro tumor model for the study of cancer biology and therapeutic treatments. 3D multicellular tumor spheroids (MCTS) have been used as reliable models of mimicking in vivo solid tumors. Macrophages and extracellular matrix (ECM), regarded as two key factors of the tumor microenvironment, play significant roles in tumor progression and drug resistance. In order to investigate their effects on tumor cell migration, a microfluidic chip-based 3D breast cancer model was developed by co-culturing monodisperse MCTS with monocytes in 3 D collagen matrix. A reversible bonding technique was employed for the fabrication of the microfluidic chip, which made it easier for MCTS formation and tailoring the MCTS co-culture conditions. When co-culturing monocytes with low invasive T47D spheroids or high invasive MD-MBA-231 spheroids, we found that T47 D cells with the stimulation of macrophage colony-stimulating factor (M-CSF) and MD-MBA-231 cells could polarize monocytes into tumor-associated macrophages (TAMs). The increased stiffness via increasing collagen concentration decreased tumor cell migration, whereas the presence of TAMs enhanced the migration ability of cells.Moreover, M-CSF-activated TAMs promoted the migration of T47 D tumor cells via the regulation of TGFβ1. Overall, this 3D co-culture microfluidic model may be useful for studying tumor progress and may offer a reliable and low-cost method for evaluation of drug efficiency.展开更多
BACKGROUND To solve the problem of liver transplantation donor insufficiency,an alternative cell transplantation therapy was investigated.We focused on amniotic epithelial cells(AECs)as a cell source because,unlike in...BACKGROUND To solve the problem of liver transplantation donor insufficiency,an alternative cell transplantation therapy was investigated.We focused on amniotic epithelial cells(AECs)as a cell source because,unlike induced pluripotent stem cells,they are cost-effective and non-tumorigenic.The utilization of AECs in regenerative medicine,however,is in its infancy.A general profile for AECs has not been comprehensively analyzed.Moreover,no hepatic differentiation protocol for AECs has yet been established.To this end,we independently compiled human AEC libraries,purified amniotic stem cells(ASCs),and co-cultured them with mesenchymal stem cells(MSCs)and human umbilical vein endothelial cell(HUVECs)in a 3D system which induces functional hepatic organoids.AIM To characterize AECs and generate functional hepatic organoids from ASCs and other somatic stem cells METHODS AECs,MSCs,and HUVECs were isolated from the placentae and umbilical cords of cesarean section patients.Amnion and primary AEC stemness characteristics and heterogeneity were analyzed by immunocytochemistry,Alkaline phosphatase(AP)staining,and flow cytometry.An adherent AEC subpopulation was selected and evaluated for ASC purification quality by a colony formation assay.AEC transcriptomes were compared with those for other hepatocytes cell sources by bioinformatics.The 2D and 3D culture were compared by relative gene expression using several differentiation protocols.ASCs,MSCs,and HUVECs were combined in a 3D co-culture system to generate hepatic organoids whose structure was compared with a 3D AEC sphere and whose function was elucidated by immunofluorescence imaging,periodic acid Schiff,and an indocyanine green(ICG)test.RESULTS AECs have certain stemness markers such as EPCAM,SSEA4,and E-cadherin.One AEC subpopulation was also either positive for AP staining or expressed the TRA-1-60 and TRA-1-81 stemness markers.Moreover,it could form colonies and its frequency was enhanced ten-fold in the adherent subpopulation after selective primary passage.Bioinfo展开更多
Multicellular magnetotactic prokaryotes （MMPs） are a group of aggregates composed of 7-45 gram-negative cells synthesizing intracellular magnetic crystals. Although they are thought to be globally distributed, MMPs ...Multicellular magnetotactic prokaryotes （MMPs） are a group of aggregates composed of 7-45 gram-negative cells synthesizing intracellular magnetic crystals. Although they are thought to be globally distributed, MMPs have been observed only in marine environments in America and Europe. Most MMPs share a rosette-like morphology and biomineralize iron sulfide crystals. In the present study, abundant MMPs were observed, with a density of 26 ind./cm^3, in the sediments of a coastal lagoon, Lake Yuehu, in the Yellow Sea. Optical microscopy showed that all of them were rosette shaped with a diameter of 5.5±0.8 μm. Transmission electron microscopy revealed that these MMPs were composed of 10- 16 ovoid cells and flagellated peritrichously. High-resolution transmission electron microscopy and energy dispersive X-ray analysis indicated that they biomineralized bullet-shaped magnetite crystals in highly organized parallel chains within which the magnetosomes were oriented in the same direction. This is the first report of MMPs from Asia and demonstrates the ubiquitous distribution of MMPs.展开更多
Traumatic brain injuries are serious clinical incidents associated with some of the poorest outcomes in neurological practice.Coupled with the limited regenerative capacity of the brain,this has significant implicatio...Traumatic brain injuries are serious clinical incidents associated with some of the poorest outcomes in neurological practice.Coupled with the limited regenerative capacity of the brain,this has significant implications for patients,carers,and healthcare systems,and the requirement for life-long care in some cases.Clinical treatment currently focuses on limiting the initial neural damage with longterm care/support from multidisciplinary teams.Therapies targeting neuroprotection and neural regeneration are not currently available but are the focus of intensive research.Biomaterial-based interventions are gaining popularity for a range of applications including biomolecule and drug delive ry,and to function as cellular scaffolds.Experimental investigations into the development of such novel therapeutics for traumatic brain injury will be critically underpinned by the availability of appropriate high thro ughput,facile,ethically viable,and pathomimetic biological model systems.This represents a significant challenge for researchers given the pathological complexity of traumatic brain injury.Specifically,there is a concerted post-injury response mounted by multiple neural cell types which includes microglial activation and astroglial scarring with the expression of a range of growth inhibito ry molecules and cytokines in the lesion environment.Here,we review common models used for the study of traumatic brain injury(ranging from live animal models to in vitro systems),focusing on penetrating traumatic brain injury models.We discuss their relative advantages and drawbacks for the developmental testing of biomaterial-based therapies.展开更多
文摘Charophytic algae and land plants together make up a monophyletic group, streptophytes, which represents one of the main lineages of multicellular eukaryotes and has contributed greatly to the change of the environment on earth in the Phanerozoic Eon. Significant progress has been made to understand phylogenetic relationships among members of this group by phylogenetic studies of morphological and molecular data over the last twenty-five years. Mesostigma viride is now regarded as among the earliest diverging unicellular organisms in streptophytes. Characeae are the sister group to land plants. Liverworts represent the first diverging lineage of land plants. Hornworts and lycophytes are extant representatives of bryophytes and vascular plants, respectively, when early land plants changed from gametophyte to sporophyte as the dominant generation in the life cycle. Equisetum, Psilotaceae, and ferns constitute the monophyletic group of monilophytes, which are sister to seed plants. Gnetales are related to conifers, not to angiosperms as previously thought. Amborella, Nymphaeales, Hydatellaceae, Illiciales, Trimeniaceae, and Austrobaileya represent the earliest diverging lineages of extant angiosperms. These phylogenetic results, together with recent progress on elucidating genetic and developmental aspects of the plant life cycle, multicellularity, and gravitropism, will facilitate evolutionary developmental studies of these key traits, which will help us to gain mechanistic understanding on how plants adapted to environmental challenges when they colonized the land during one of the major transitions in evolution of life.
基金supported by the National Natural Science Foundation of China(31530084,32000558,32000483,and31800504)the Programme of Introducing Talents of Discipline to Universities(111 project,B13007)the China Postdoctoral Science Foundation Grant(2019M660494)。
文摘In multicellular and even single-celled organisms,individual components are interconnected at multiscale levels to produce enormously complex biological networks that help these systems maintain homeostasis for development and environmental adaptation.Systems biology studies initially adopted network analysis to explore how relationships between individual components give rise to complex biological processes.Network analysis has been applied to dissect the complex connectivity of mammalian brains across different scales in time and space in The Human Brain Project.In plant science,network analysis has similarly been applied to study the connectivity of plant components at the molecular,subcellular,cellular,organic,and organism levels.Analysis of these multiscale networks contributes to our understanding of how genotype determines phenotype.In this review,we summarized the theoretical framework of plant multiscale networks and introduced studies investigating plant networks by various experimental and computational modalities.We next discussed the currently available analytic methodologies and multi-level imaging techniques used to map multiscale networks in plants.Finally,we highlighted some of the technical challenges and key questions remaining to be addressed in this emerging field.
基金National Natural Science Foundation of China,Grant/Award Numbers:82072396,32271379CAMS Innovation Fund for Medical Sciences,Grant/Award Numbers:CIFMS,2019-I2M-5-037+3 种基金Shanghai's Top Priority Research Center,Grant/Award Number:2022ZZ01017Interdisciplinary Program of Shanghai Jiao Tong University,Grant/Award Number:YG2021ZD12Science and Technology Commission of Shanghai Municipality,Grant/Award Number:21490711700Science and Technology Project of Xuzhou Health Commission,Grant/Award Number:XWKYHT20230077。
文摘Due to tissue lineage variances and the anisotropic physiological character-istics,regenerating complex osteochondral tissues(cartilage and subchondral bone)remains a great challenge,which is primarily due to the distinct requirements for cartilage and subchondral bone regeneration.For cartilage regeneration,a significant amount of newly generated chondrocytes is required while maintaining their phenotype.Conversely,bone regeneration necessitates inducing stem cells to differentiate into osteoblasts.Additionally,the construction of the osteochondral interface is crucial.In this study,we fabricated a biphasic multicellular bioprinted scaffold mimicking natural osteochondral tissue employing three-dimensional(3D)bioprinting technol-ogy.Briefly,gelatin-methacryloyl(GelMA)loaded with articular chondrocytes and bone marrow mesenchymal stem cells(ACs/BMSCs),serving as the cartilage layer,preserved the phenotype of ACs and promoted the differentia-tion of BMSCs into chondrocytes through the interaction between ACs and BMSCs,thereby facilitating cartilage regeneration.GelMA/strontium-substituted xonotlite(Sr-CSH)loaded with BMSCs,serving as the subchondral bone layer,regulated the differentiation of BMSCs into osteoblasts and enhanced the secretion of cartilage matrix by ACs in the cartilage layer through the slow release of bioactive ions from Sr-CSH.Additionally,GelMA,serving as the matrix material,contributed to the reconstruction of the osteochondral interface.Ultimately,this biphasic multicellular bioprinted scaffold demonstrated satisfactory simultaneous regeneration of osteochondral defects.In this study,a promising strategy for the application of 3D bioprinting technology in complex tissue regeneration was proposed.
基金supported by NYUAD Faculty Research Funds(AD060)Tamkeen under the NYU Abu Dhabi Research Institute Award to the NYUAD Center for Genomics and Systems Biology(7371210 CGSB9)。
文摘Macroalgae are multicellular,aquatic autotrophs that play vital roles in global climate maintenance and have diverse applications in biotechnology and eco-engineering,which are directly linked to their multicellularity phenotypes.However,their genomic diversity and the evolutionary mechanisms underlying multicellularity in these organisms remain uncharacterized.In this study,we sequenced 110 macroalgal genomes from diverse climates and phyla,and identified key genomic features that distinguish them from their microalgal relatives.Genes for cell adhesion,extracellular matrix formation,cell polarity,transport,and cell differentiation distinguish macroalgae from microalgae across all three major phyla,constituting conserved and unique gene sets supporting multicellular processes.Adhesome genes show phylum-and climate-specific expansions that may facilitate niche adaptation.Collectively,our study reveals genetic determinants of convergent and divergent evolutionary trajectories that have shaped morphological diversity in macroalgae and provides genome-wide frameworks to understand photosynthetic multicellular evolution in aquatic environments.
文摘背景:组织工程骨构建体的血管化性能不足是限制骨组织工程用于修复大尺寸骨缺损临床应用的主要挑战。目的:对近年来利用骨形成细胞和血管生成细胞构建组织工程构建体(基于支架或无支架)在骨修复中的应用进行了概述,以期实现组织工程骨可持续的血管生成及生成功能完善的血管,从而提高骨组织工程在大尺寸骨缺损修复应用中的细胞存活率、并为促进骨的形成和重塑提供参考。方法:应用计算机对中国知网、PubMed及Web of Science数据库2000-2021年发表的文献进行了检索,中文检索词为“骨组织工程、成骨成血管、多细胞”,英文检索词为“Bone Tissue Engineering,Osteogenesis and angiogenesis,Multicellular”,根据纳入和排除标准,最终纳入63篇文献进行结果分析。结果与结论:①目前最常用的骨形成细胞主要有间充质干细胞、脂肪干细胞和成骨细胞,常用的血管生成细胞有人脐静脉内皮细胞和内皮祖细胞。②支架内包封细胞在实现各类细胞的精准定位方面优于在支架上接种细胞。③将两种单一细胞膜片相叠加或者共培养单层细胞膜片相叠加的方法,可以调控各类细胞的位置,从而构建血管化网络。④目前,基于支架的组织工程技术还需克服支架降解速率与组织再生速率的不匹配性、细胞与生物材料相互作用不可控等问题,而基于无支架细胞膜片的组织工程还需要克服力学强度低的难题。⑤未来研究需构建具有临床所需大小的功能性3D血管化组织工程骨,还需关注包括细胞培养和生物学作用机制;结合组织工程、细胞工程和基因工程构建组织工程骨,有望实现刺激早期血管生成、保持血液循环,防止构建体内部的细胞死亡,并起到加速构建体修复临床大体积骨缺损的作用。
文摘Escherichia coli RecA has been considered traditionally a cellular protein with multiple vital functions working to ensure the maintenance of integrity of genome in each individual bacterial cell as well as promoting swarming migration in collectivity. On the contrary, recently it has been described that RecA promotes cellular apoptotic-like death (ALD), a pathway of programmed cellular death (PCD). In fact, RecA has been dubbed as the major apoptotic executor in E. coli. From these studies, RecA emerges as a prototypical Gin/Gan protein that despite of their intrinsic vital and lethal anfi-funcionality becomes in a WISE factor: a Worker to Integrate Survival and Evolution in E. coli evolving populations living in community. Here, I provide a review of recent experimental and conceptual advances trying to understand these RecA’s antagonistic roles in appearance contradictory under a unified biological vision.
文摘Cilia and flagella are organelles of motility that enable cells to swim or move liquid over its surface. An exhaustive literature survey for the presence of the organelle in organisms across phyla showed that most animal cells harbor cilia in contrast to very few fungal cells. While this was not unexpected, it was the position and arrangement of this organelle in each cell that intrigued our attention. Natural selection might have favored motility over chemotaxis;and it would have done so to evolve a stable structure that could have undergone an optimization process requiring a precise geometry in the shape of cells and the structure that would help cells to move. The positioning of such a structure would play a pre-dominant role in optimal motility. It is now known that the flagellar position of a cell is a genetically distinct trait, occasionally used in phylogeny of bacteria, distributed in distinguishing patterns over cellular surface, but basically are of two types, either polar (one flagellum arising from one pole per cell) or peritrichous (lateral flagella distributed over the entire cell surface). Irrespective of the cellular habitat, flagella origin, ultrastructure and proteome, the present investigation surveyed 26 sub-types of flagellar arrangements from as many species as possible. A peculiar pattern ensued-Prokaryotes harbored predominantly polar and peritrichous types;eukaryotes showed a mere change of the peritrichous one. These numbers when used to create a Similarity tree depicted a similarity distance of 14 between the Eubacteria and Archaebacteria forming the first neighborhood;Protozoans, Algae, Fungi, Plantae and Animalia formed a second neighborhood. We offer a working hypothesis for this pattern and the gradual shift in the flagellar arrangement from polar, peritrichous, sub-apical, and apical to lateral throughout evolution.
文摘In 1997 and 1998, hundreds of specimens of megascopic carbonaceous compressions or algal fossils were found from - 1800-million-year old Changzhougou Formation, which is the lowermost unit of the latest Palaeoproterozoic Changcheng Group (~1 600-1 800 Ma) in the Xinglong-Kuancheng areas at the middle Yanshan Range, North China. They are discoid, ellipsoid and sausage-like, namely shaped like Chuaria Shouhsiennia (Ellipsophyta) and Tawuia. By adopting HF acid-resistant maceration coupled with scanning electron microscope and petrologic section, the authors made a preliminary research on the histology for some circular and ellipsoid carbonaceous compressions, namely Chuaria- and Shouhsienia-llke forms, in addition to their morphology. The following three types of multicellular tissues have been found in the fragments of them: colony-like, pseudoparenchyma-like and parenchyma-like. All of the new data about multicelluar tissues not only supply a very important basis in histology to determine the
基金supported by the China 973 Program(2012CB113900)National Natural Science Foundation of China(31271291,31471156)+2 种基金Shanghai Municipal Committee of Science and Technology(13JC1403600)China Innovative Research Team,Ministry of EducationShanghai Graduate Education and Innovation Program (Horticulture)
文摘Plant trichomes serve as a highly suitable model for investigating cell differentiation at the single-cell level. The regulatory genes involved in unicellular trichome develop- ment in Arabidopsis thaliana have been intensively studied, but genes regulating multicellular trichome development in plants remain unclear. Here, we characterized Cucumis sativus （cucumber） trichomes as representative multicellular and unbranched structures, and identified Micro-trichome （Mict）, using map-based cloning in an F2 segregating population of 7,936 individuals generated from a spontaneous mict mutant. In mitt plants, trichomes in both leaves and fruits, are small, poorly developed, and denser than in the wild type. Sequence analysis revealed that a 2,649-bp genomic deletion, spanning the first and second exons, occurred in a plant-specific class I homeodomain-leucine zipper gene. Tissue-specific expression analysis indicated that Mict is strongly expressed in the trichome cells. Transcriptome profiling identified potential targets of Mict including putative homologs of genes known in other systems to regulate trichome development, meristem determinacy, and hormone responsiveness. Phylo- genic analysis charted the relationships among putative homologs in angiosperms. Our paper represents initial steps toward understanding the development of multicellular trichomes.
基金This work was supported by a fund for doctorate candidate scientific research from the Ministry of Education (98042303)doctor start fund of Suzhou University (Q4114928)
文摘Vegetative cells of Porphyra yezoensis are isolated with sea snail enzyme and cultured on the solidified agar medium. The results of experiments show that the isolated cells can survive,divide and regenerate well on the medium solidified with agar. The first division on the solid medium starts after 7 days' culture, 4 days later than the liquid culture. The survival rate of isolated cells is 71.3% on the solid medium, lower than the 86.2% of that in seawater.Thalli, thalloids,conchocelis, spermatangia and multicellular masses are developed on the solid/medium in the first month, slowly but normally. Spermatangia sacs disappear within 4 weeks. Without adding nutrient liquid onto the surface of solid medium or injecting seawater under the agar layer in order to keep moisture, the thalli and cell groups release monospores to form new thalli instead of enlarging their areas after 5 weeks' culturing. Some monospores regenerate new thalli. Other monospores lose their pigments and minimize their volume and divide quickly to form light pink calli. After 16 weeks, numerous calli can be seen on the solid medium and after 24 weeks' culturing, almost only calli and conchocelis can be seen. If the calli are immersed in seawater, the monospores are released and may develop into young thallus.
文摘Until recently, ovarian cancer research has mainly focused on the tumor cells themselves ignoring for the most part the surrounding tumor environment which includes malignant peritoneal effusions. However, one of the major conceptual advances in oncology over the last few years has been the appreciation that cancer progression cannot be explained by aberrations in cancer cells themselves and is strongly influenced by the surrounding tumor environment. The mechanisms of ovarian cancer progression differ from that of other solid tumors because ovarian cancer cells primarily disseminate within the peritoneal cavity.Malignant peritoneal effusion accumulates in the peritoneal cavity during ovarian cancer progression. These exudative fluids act as a unique tumor environment providing a framework that orchestrates cellular and molecular changes contributing to aggressiveness and disease progression. The composition of ascites, which includes cellular and acellular components, constantly adapts during the course of the disease in response to various cellular cues originating from both tumor and stromal cells. The tumor environment that represents peritoneal effusions closely constitute an ecosystem, with specific cell types and signaling molecules increasing and decreasing during the course of the disease progression creating a single complex network. Although recent advances aiming to understand the ovarian tumor environment have focused one at a time on components, the net impact of the whole environment cannot be understood simply from its parts or outside is environmental context.
文摘Multicellular layers(MCLs) have previously been used to determine the pharmacokinetics of a variety of different cancer drugs including paclitaxel, doxorubicin, methotrexate, and 5-fluorouracil across a number of cell lines. It is not known how nanoparticles(NPs) navigate through the tumor microenvironment once they leave the tumor blood vessel.In this study, we used the MCL model to study the uptake and penetration dynamics of NPs. Gold nanoparticles(GNPs)were used as a model system to map the NP distribution within tissue-like structures. Our results show that NP uptake and transport are dependent on the tumor cell type. MDA-MB-231 tissue showed deeper penetration of GNPs as compared to MCF-7 one. Intracellular and extracellular distributions of NPs were mapped using Cyto Viva imaging. The ability of MCLs to mimic tumor tissue characteristics makes them a useful tool in assessing the efficacy of particle distribution in solid tumors.
基金supported by the National Natural Science Foundation of China(41030209,41130209and40625006)the Chinese Academy of Sciences(KZZD-EW02,KZCX2-YW-153and KZCX2-EW-119)
文摘The Lantian biota at the Lantian Town of Xiuning County, Anhui Province, is preserved in black shales of the Ediacaran Lantian Formation. It yields some of the oldest known complex macroorganisms, including fan-shaped seaweeds and possible animal fossils with tentacles and intestinal-like structures reminiscent of modern coelenterates and bilaterians. The Lantian Lagerst^itte sheds new light on the origin and early evolution of multicellular organisms in relatively quiet and deep environments soon after the Neoproterozoic Marinoan glaciation. The morphological complexity and diversity of early multicellular organisms may be closely related to sexual reproduction and alternation of generations. The fluctuation of oceanic redox conditions during this peri- od may have played a role in the ecology and preservation of the Lantian biota.
基金supported by the National Natural Science Foundation of China (Nos. 21675096 and 21475073)Youth Scientific Research Funds from Graduate School at Shenzhen, Tsinghua University (No. QN20160002)
文摘Recapitulating the tumor microenvironment is a major challenge in the development of in vitro tumor model for the study of cancer biology and therapeutic treatments. 3D multicellular tumor spheroids (MCTS) have been used as reliable models of mimicking in vivo solid tumors. Macrophages and extracellular matrix (ECM), regarded as two key factors of the tumor microenvironment, play significant roles in tumor progression and drug resistance. In order to investigate their effects on tumor cell migration, a microfluidic chip-based 3D breast cancer model was developed by co-culturing monodisperse MCTS with monocytes in 3 D collagen matrix. A reversible bonding technique was employed for the fabrication of the microfluidic chip, which made it easier for MCTS formation and tailoring the MCTS co-culture conditions. When co-culturing monocytes with low invasive T47D spheroids or high invasive MD-MBA-231 spheroids, we found that T47 D cells with the stimulation of macrophage colony-stimulating factor (M-CSF) and MD-MBA-231 cells could polarize monocytes into tumor-associated macrophages (TAMs). The increased stiffness via increasing collagen concentration decreased tumor cell migration, whereas the presence of TAMs enhanced the migration ability of cells.Moreover, M-CSF-activated TAMs promoted the migration of T47 D tumor cells via the regulation of TGFβ1. Overall, this 3D co-culture microfluidic model may be useful for studying tumor progress and may offer a reliable and low-cost method for evaluation of drug efficiency.
基金Supported by National Natural Science Foundation of China,No.81770621Ministry of Education,Culture,Sports,Science,and Technology of Japan,KAKENHI,No.16K15604,No.18H02866Japan Science and Technology Agency-Japan International Cooperation Agency’s(JST-JICA)Science and Technology Research Partnership for Sustainable Development(SATREPS)Project
文摘BACKGROUND To solve the problem of liver transplantation donor insufficiency,an alternative cell transplantation therapy was investigated.We focused on amniotic epithelial cells(AECs)as a cell source because,unlike induced pluripotent stem cells,they are cost-effective and non-tumorigenic.The utilization of AECs in regenerative medicine,however,is in its infancy.A general profile for AECs has not been comprehensively analyzed.Moreover,no hepatic differentiation protocol for AECs has yet been established.To this end,we independently compiled human AEC libraries,purified amniotic stem cells(ASCs),and co-cultured them with mesenchymal stem cells(MSCs)and human umbilical vein endothelial cell(HUVECs)in a 3D system which induces functional hepatic organoids.AIM To characterize AECs and generate functional hepatic organoids from ASCs and other somatic stem cells METHODS AECs,MSCs,and HUVECs were isolated from the placentae and umbilical cords of cesarean section patients.Amnion and primary AEC stemness characteristics and heterogeneity were analyzed by immunocytochemistry,Alkaline phosphatase(AP)staining,and flow cytometry.An adherent AEC subpopulation was selected and evaluated for ASC purification quality by a colony formation assay.AEC transcriptomes were compared with those for other hepatocytes cell sources by bioinformatics.The 2D and 3D culture were compared by relative gene expression using several differentiation protocols.ASCs,MSCs,and HUVECs were combined in a 3D co-culture system to generate hepatic organoids whose structure was compared with a 3D AEC sphere and whose function was elucidated by immunofluorescence imaging,periodic acid Schiff,and an indocyanine green(ICG)test.RESULTS AECs have certain stemness markers such as EPCAM,SSEA4,and E-cadherin.One AEC subpopulation was also either positive for AP staining or expressed the TRA-1-60 and TRA-1-81 stemness markers.Moreover,it could form colonies and its frequency was enhanced ten-fold in the adherent subpopulation after selective primary passage.Bioinfo
基金Supported by the National Natural Science Foundation of China(Nos. 40906069,40776094)Shangdong 908 Project (No. SD-908-02-08)+1 种基金the Haiwaijiechuxuezhe-Fund of Chinese Academy of Sciences (No.2006-1-15)K. C. WONG Education Foundation
文摘Multicellular magnetotactic prokaryotes （MMPs） are a group of aggregates composed of 7-45 gram-negative cells synthesizing intracellular magnetic crystals. Although they are thought to be globally distributed, MMPs have been observed only in marine environments in America and Europe. Most MMPs share a rosette-like morphology and biomineralize iron sulfide crystals. In the present study, abundant MMPs were observed, with a density of 26 ind./cm^3, in the sediments of a coastal lagoon, Lake Yuehu, in the Yellow Sea. Optical microscopy showed that all of them were rosette shaped with a diameter of 5.5±0.8 μm. Transmission electron microscopy revealed that these MMPs were composed of 10- 16 ovoid cells and flagellated peritrichously. High-resolution transmission electron microscopy and energy dispersive X-ray analysis indicated that they biomineralized bullet-shaped magnetite crystals in highly organized parallel chains within which the magnetosomes were oriented in the same direction. This is the first report of MMPs from Asia and demonstrates the ubiquitous distribution of MMPs.
基金funded by awards from the EPSRC Doctoral Training Centre in Regenerative Medicine and an NHS bursary。
文摘Traumatic brain injuries are serious clinical incidents associated with some of the poorest outcomes in neurological practice.Coupled with the limited regenerative capacity of the brain,this has significant implications for patients,carers,and healthcare systems,and the requirement for life-long care in some cases.Clinical treatment currently focuses on limiting the initial neural damage with longterm care/support from multidisciplinary teams.Therapies targeting neuroprotection and neural regeneration are not currently available but are the focus of intensive research.Biomaterial-based interventions are gaining popularity for a range of applications including biomolecule and drug delive ry,and to function as cellular scaffolds.Experimental investigations into the development of such novel therapeutics for traumatic brain injury will be critically underpinned by the availability of appropriate high thro ughput,facile,ethically viable,and pathomimetic biological model systems.This represents a significant challenge for researchers given the pathological complexity of traumatic brain injury.Specifically,there is a concerted post-injury response mounted by multiple neural cell types which includes microglial activation and astroglial scarring with the expression of a range of growth inhibito ry molecules and cytokines in the lesion environment.Here,we review common models used for the study of traumatic brain injury(ranging from live animal models to in vitro systems),focusing on penetrating traumatic brain injury models.We discuss their relative advantages and drawbacks for the developmental testing of biomaterial-based therapies.
