Maize is one of the most important crops in the world and is also an essential raw material for the food, fuel, and fodder industries. Maize hybrids are widely used today, and gain of elite inbred lines is a crucial s...Maize is one of the most important crops in the world and is also an essential raw material for the food, fuel, and fodder industries. Maize hybrids are widely used today, and gain of elite inbred lines is a crucial step for hybrid breeding.展开更多
Maize（Zea mays） root system architecture（RSA）mediates the key functions of plant anchorage and acquisition of nutrients and water. In this study,a set of 204 recombinant inbred lines（RILs） was derived from the w...Maize（Zea mays） root system architecture（RSA）mediates the key functions of plant anchorage and acquisition of nutrients and water. In this study,a set of 204 recombinant inbred lines（RILs） was derived from the widely adapted Chinese hybrid ZD958（Zheng58 Chang7-2）,genotyped by sequencing（GBS） and evaluated as seedlings for 24 RSA related traits divided into primary,seminal and total root classes. Signi ficant differences between the means of the parental phenotypes were detected for 18 traits,and extensive transgressive segregation in the RIL population was observed for all traits. Moderate to strong relationships among the traits were discovered. A total of 62 quantitative trait loci（QTL） were identi fied that individually explained from1.6% to 11.6%（total root dry weight/total seedling shoot dry weight） of the phenotypic variation. Eighteen,24 and 20 QTL were identi fied for primary,seminal and total root classes of traits,respectively. We found hotspots of 5,3,4 and 12 QTL in maize chromosome bins 2.06,3.02-03,9.02-04,and 9.05-06,respectively,implicating the presence of root gene clusters or pleiotropic effects. These results characterized the phenotypic variation and genetic architecture of seedling RSA in a population derived from a successful maize hybrid.展开更多
CRISPR/Cas （clustered regularly interspaced short palindromic repeats/CR1SPR-associated proteins） is an adaptive immune system in bacteria and archaea to defend against invasion from foreign DNA fragments. Recently,...CRISPR/Cas （clustered regularly interspaced short palindromic repeats/CR1SPR-associated proteins） is an adaptive immune system in bacteria and archaea to defend against invasion from foreign DNA fragments. Recently, it has been developed as a powerful targeted genome editing tool for a wide variety of species. However, its application in maize has only been tested with transiently expressed somatic cells or with a limited number of stable transgenic To plants. The exact efficiency and specificity of the CRISPR/Cas system in the highly complex maize genome has not been documented yet. Here we report an extensive study of the well-studied type II CRISPR-Cas9 system for targeted genome editing in maize, with the codon-optimized Cas9 protein and the short non-coding guide RNA generated through a functional maize U6 snRNA promoter. Targeted gene mutagenesis was detected for 90 loci by maize protoplast assay, with an average cleavage efficiency of 10.67 %. Stable knockout transformants for maize phytoene synthase gene （PSYI） were obtained. Mutations occurred in germ ceils can be stably inherited to the next generation. Moreover, no off-target effect was detected at the computationally predicted putative off-target loci. No significant difference between the transcriptomes of the Cas9 expressed and non-expressed lines was detected. Our results confirmed that the CRISPR-Cas9 could be successfully applied as a robust targeted genome editing system in maize.展开更多
Southern corn rust(SCR),caused by the fungal pathogen Puccinia polysora,is a major threat to maize pro-duction worldwide.Efficient breeding and deployment of resistant hybrids are key to achieving durable control of S...Southern corn rust(SCR),caused by the fungal pathogen Puccinia polysora,is a major threat to maize pro-duction worldwide.Efficient breeding and deployment of resistant hybrids are key to achieving durable control of SCR.Here,we report the molecular cloning and characterization of RppC,which encodes an NLR-type immune receptor and is responsible for a major SCR resistance quantitative trait locus.Further-more,we identified the corresponding avirulence effector,AvrRppC,which is secreted by P.polysora and triggers RppC-mediated resistance.Allelic variation of AvrRppC directly determines the effectiveness of RppC-mediated resistance,indicating that monitoring of AvrRppC variants in the field can guide the rational deployment of RppC-containing hybrids in maize production.Currently,RppC is the most frequently deployed SCR resistance gene in China,and a better understanding of its mode of action is crit-ical for extending its durability.展开更多
RNA editing is a posttranscriptional process that is important in mitochondria and plastids of higher plants. All RNA editing-specific trans-factors reported so far belong to PLS-class of pentatricopeptide repeat(PPR)...RNA editing is a posttranscriptional process that is important in mitochondria and plastids of higher plants. All RNA editing-specific trans-factors reported so far belong to PLS-class of pentatricopeptide repeat(PPR)proteins. Here, we report the map-based cloning and molecular characterization of a defective kernel mutant dek39 in maize. Loss of Dek39 function leads to delayed embryogenesis and endosperm development, reduced kernel size, and seedling lethality. Dek39 encodes an E subclass PPR protein that targets to both mitochondria and chloroplasts, and is involved in RNA editing in mitochondrial NADH dehydrogenase3(nad3) at nad3-247 and nad3-275. C-to-U editing of nad3-275 is not conserved and even lost in Arabidopsis, consistent with the idea that no close DEK39 homologs are present in Arabidopsis. However, the amino acids generated by editing nad3-247 and nad3-275 are highly conserved in many other plant species, and the reductions of editing at these two sites decrease the activity of mitochondria NADH dehydrogenase complex I,indicating that the alteration of amino acid sequence is necessary for Nad3 function. Our results indicate that Dek39 encodes an E sub-class PPR protein that is involved in RNA editing of multiple sites and is necessary for seed development of maize.展开更多
Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease,but the genetics and mechanisms of resistance are not well understood.In this study,GWAS performed by MLM and 3VmrMLM identi...Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease,but the genetics and mechanisms of resistance are not well understood.In this study,GWAS performed by MLM and 3VmrMLM identified 40 and 20 QTNs,associated with seedling blight resistance.These methods identified 49 and 36 genes,respectively.Functional verification of candidate gene ZmSBR1 identified by both methods showed that the resistance of a mutant line to seedling blight decreased by 0.37 grade points after inoculation with F.verticillioides,compared with the WT.The length of the stem rot lesion caused by F.verticillioides increased by 86%in mutant seedlings,and the relative length of the adult plant stalk rot increased by 35%in mutant plants compared to the wild type after inoculation with Fusarium graminearum.Transcriptome analysis showed that expression of defense-related genes after inoculation was down-regulated in the mutant compared to the wild type,synthesis of secondary metabolites associated with resistance was reduced,and the immune response triggered by PAMP decreased,resulting in decreased resistance of mutant maize seedlings.Candidate gene association analysis showed that most maize inbred lines carried the susceptible haplotype.A functional PCR marker was developed.The results demonstrated that ZmSBR1 conferred resistance to multiple Fusarium diseases at the seedling and adult growth stages and had important application value in breeding.展开更多
As the global human population continues to grow and is predicted to reach 10 billion by 2050,the demand for food volume and quality raises a tremendous challenge(OECD/FAO,2017).The worldwide arable land area is decre...As the global human population continues to grow and is predicted to reach 10 billion by 2050,the demand for food volume and quality raises a tremendous challenge(OECD/FAO,2017).The worldwide arable land area is decreasing,posing a major threat to crop production.To address these problems,we need to improve the endurance of major crops.展开更多
背景:心肌损伤修复过程涉及复杂的细胞和分子机制,尤其是线粒体钙稳态、巨噬细胞的自噬与焦亡途径。中药在改善心肌损伤方面有显著的临床疗效,但其作用机制尚需深入研究。目的:探讨线粒体钙稳态介导的巨噬细胞自噬与焦亡途径在心肌损伤...背景:心肌损伤修复过程涉及复杂的细胞和分子机制,尤其是线粒体钙稳态、巨噬细胞的自噬与焦亡途径。中药在改善心肌损伤方面有显著的临床疗效,但其作用机制尚需深入研究。目的:探讨线粒体钙稳态介导的巨噬细胞自噬与焦亡途径在心肌损伤中的作用,并总结中药在这一领域的研究进展。方法:计算机检索Web of Science、PubMed及中国知网等数据库,从建库至2024年3月的相关文献。中文检索词为“线粒体钙稳态,巨噬细胞自噬,巨噬细胞焦亡,中药,心肌损伤,心肌损伤再灌注”等;英文检索词为“Mitochondrial calcium homeostasis,Macrophage autophagy,Macrophage pyroptosis,Traditional Chinese medicine,Myocardial injury”等。通过文献回顾分析线粒体钙稳态与巨噬细胞自噬、焦亡之间的关系,探究其在心肌损伤中的作用机制,总结中药多靶点、多通路影响的途径。结果与结论:①研究发现,线粒体钙稳态的维持与心肌细胞功能的正常运转密切相关。巨噬细胞可通过自噬与焦亡途径参与心肌损伤的修复过程,自噬有助于细胞的清除和炎症反应的调节,而焦亡则可通过释放炎症因子影响心肌修复。②中医药通过多种机制调节线粒体钙稳态和巨噬细胞功能,如黄芪甲苷通过降低线粒体膜电位和抑制细胞色素C来调节钙稳态,淫羊藿苷通过减少β-淀粉样蛋白沉积来发挥作用;中药复方和单味药物通过激活或抑制特定的信号通路,如PI3K/AKT、核因子κB等通路来促进心肌损伤的修复。③未来的研究应关注线粒体钙稳态、自噬与焦亡途径的相互作用,以及中药如何通过这些途径发挥治疗作用,为心肌损伤的治疗提供新的策略和药物。展开更多
文摘Maize is one of the most important crops in the world and is also an essential raw material for the food, fuel, and fodder industries. Maize hybrids are widely used today, and gain of elite inbred lines is a crucial step for hybrid breeding.
基金supported by 863 Project (2012AA10A305)Chinese Universities Scientific Fund (2014XJ036)+1 种基金NSF (31301321)948 Project (2011-G15)
文摘Maize（Zea mays） root system architecture（RSA）mediates the key functions of plant anchorage and acquisition of nutrients and water. In this study,a set of 204 recombinant inbred lines（RILs） was derived from the widely adapted Chinese hybrid ZD958（Zheng58 Chang7-2）,genotyped by sequencing（GBS） and evaluated as seedlings for 24 RSA related traits divided into primary,seminal and total root classes. Signi ficant differences between the means of the parental phenotypes were detected for 18 traits,and extensive transgressive segregation in the RIL population was observed for all traits. Moderate to strong relationships among the traits were discovered. A total of 62 quantitative trait loci（QTL） were identi fied that individually explained from1.6% to 11.6%（total root dry weight/total seedling shoot dry weight） of the phenotypic variation. Eighteen,24 and 20 QTL were identi fied for primary,seminal and total root classes of traits,respectively. We found hotspots of 5,3,4 and 12 QTL in maize chromosome bins 2.06,3.02-03,9.02-04,and 9.05-06,respectively,implicating the presence of root gene clusters or pleiotropic effects. These results characterized the phenotypic variation and genetic architecture of seedling RSA in a population derived from a successful maize hybrid.
基金supported by the grants from the National Natural Science Foundation of China(Nos.31225020,31421005,and 91435206)grant from the National High Technology Research and Development of China(No.2012AA10A305)2011-G15 from the‘948’project
文摘CRISPR/Cas （clustered regularly interspaced short palindromic repeats/CR1SPR-associated proteins） is an adaptive immune system in bacteria and archaea to defend against invasion from foreign DNA fragments. Recently, it has been developed as a powerful targeted genome editing tool for a wide variety of species. However, its application in maize has only been tested with transiently expressed somatic cells or with a limited number of stable transgenic To plants. The exact efficiency and specificity of the CRISPR/Cas system in the highly complex maize genome has not been documented yet. Here we report an extensive study of the well-studied type II CRISPR-Cas9 system for targeted genome editing in maize, with the codon-optimized Cas9 protein and the short non-coding guide RNA generated through a functional maize U6 snRNA promoter. Targeted gene mutagenesis was detected for 90 loci by maize protoplast assay, with an average cleavage efficiency of 10.67 %. Stable knockout transformants for maize phytoene synthase gene （PSYI） were obtained. Mutations occurred in germ ceils can be stably inherited to the next generation. Moreover, no off-target effect was detected at the computationally predicted putative off-target loci. No significant difference between the transcriptomes of the Cas9 expressed and non-expressed lines was detected. Our results confirmed that the CRISPR-Cas9 could be successfully applied as a robust targeted genome editing system in maize.
基金supported by grants from the National Key Research and Development Program of China(2021YFF1000302)the National Natural Science Foundation of China(31901550)+2 种基金the Ministry of Science and Technology of China(2016YFD0101803)the National Natural Science Foundation of China(31501326)Innovative Talents in Colleges and Universities of Henan Province(19HASTIT010)was a funding pro-vided by Henan Province government of China.
文摘Southern corn rust(SCR),caused by the fungal pathogen Puccinia polysora,is a major threat to maize pro-duction worldwide.Efficient breeding and deployment of resistant hybrids are key to achieving durable control of SCR.Here,we report the molecular cloning and characterization of RppC,which encodes an NLR-type immune receptor and is responsible for a major SCR resistance quantitative trait locus.Further-more,we identified the corresponding avirulence effector,AvrRppC,which is secreted by P.polysora and triggers RppC-mediated resistance.Allelic variation of AvrRppC directly determines the effectiveness of RppC-mediated resistance,indicating that monitoring of AvrRppC variants in the field can guide the rational deployment of RppC-containing hybrids in maize production.Currently,RppC is the most frequently deployed SCR resistance gene in China,and a better understanding of its mode of action is crit-ical for extending its durability.
基金supported by the National Natural Science Foundation of China (91435206 31421005)+1 种基金National Key Technologies Research & Development ProgramSeven Major Crops Breeding Project (2016YFD0101803, 2016YFD0100404)the 948 project (2016-X33)
文摘RNA editing is a posttranscriptional process that is important in mitochondria and plastids of higher plants. All RNA editing-specific trans-factors reported so far belong to PLS-class of pentatricopeptide repeat(PPR)proteins. Here, we report the map-based cloning and molecular characterization of a defective kernel mutant dek39 in maize. Loss of Dek39 function leads to delayed embryogenesis and endosperm development, reduced kernel size, and seedling lethality. Dek39 encodes an E subclass PPR protein that targets to both mitochondria and chloroplasts, and is involved in RNA editing in mitochondrial NADH dehydrogenase3(nad3) at nad3-247 and nad3-275. C-to-U editing of nad3-275 is not conserved and even lost in Arabidopsis, consistent with the idea that no close DEK39 homologs are present in Arabidopsis. However, the amino acids generated by editing nad3-247 and nad3-275 are highly conserved in many other plant species, and the reductions of editing at these two sites decrease the activity of mitochondria NADH dehydrogenase complex I,indicating that the alteration of amino acid sequence is necessary for Nad3 function. Our results indicate that Dek39 encodes an E sub-class PPR protein that is involved in RNA editing of multiple sites and is necessary for seed development of maize.
基金supported by grants from the National Key Research and Development Program Project of China(2022YFD1201803)Research on Resistance Genetics of Maize Root Rot Disease,State Key Laboratory of Agronomy College,Henan Agricultural University,China(39990073/111)。
文摘Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease,but the genetics and mechanisms of resistance are not well understood.In this study,GWAS performed by MLM and 3VmrMLM identified 40 and 20 QTNs,associated with seedling blight resistance.These methods identified 49 and 36 genes,respectively.Functional verification of candidate gene ZmSBR1 identified by both methods showed that the resistance of a mutant line to seedling blight decreased by 0.37 grade points after inoculation with F.verticillioides,compared with the WT.The length of the stem rot lesion caused by F.verticillioides increased by 86%in mutant seedlings,and the relative length of the adult plant stalk rot increased by 35%in mutant plants compared to the wild type after inoculation with Fusarium graminearum.Transcriptome analysis showed that expression of defense-related genes after inoculation was down-regulated in the mutant compared to the wild type,synthesis of secondary metabolites associated with resistance was reduced,and the immune response triggered by PAMP decreased,resulting in decreased resistance of mutant maize seedlings.Candidate gene association analysis showed that most maize inbred lines carried the susceptible haplotype.A functional PCR marker was developed.The results demonstrated that ZmSBR1 conferred resistance to multiple Fusarium diseases at the seedling and adult growth stages and had important application value in breeding.
基金supported by the National Natural Science Foundation of China(32271541)the National Key Research and Development Program of China(2021YFD1200701)+1 种基金Key Project of Maize Germplasm Improvement(2022010202,B21HJ0509)supported by Pinduoduo-China Agricultural University Research Fund(PC2023A01004)。
文摘As the global human population continues to grow and is predicted to reach 10 billion by 2050,the demand for food volume and quality raises a tremendous challenge(OECD/FAO,2017).The worldwide arable land area is decreasing,posing a major threat to crop production.To address these problems,we need to improve the endurance of major crops.
文摘背景:心肌损伤修复过程涉及复杂的细胞和分子机制,尤其是线粒体钙稳态、巨噬细胞的自噬与焦亡途径。中药在改善心肌损伤方面有显著的临床疗效,但其作用机制尚需深入研究。目的:探讨线粒体钙稳态介导的巨噬细胞自噬与焦亡途径在心肌损伤中的作用,并总结中药在这一领域的研究进展。方法:计算机检索Web of Science、PubMed及中国知网等数据库,从建库至2024年3月的相关文献。中文检索词为“线粒体钙稳态,巨噬细胞自噬,巨噬细胞焦亡,中药,心肌损伤,心肌损伤再灌注”等;英文检索词为“Mitochondrial calcium homeostasis,Macrophage autophagy,Macrophage pyroptosis,Traditional Chinese medicine,Myocardial injury”等。通过文献回顾分析线粒体钙稳态与巨噬细胞自噬、焦亡之间的关系,探究其在心肌损伤中的作用机制,总结中药多靶点、多通路影响的途径。结果与结论:①研究发现,线粒体钙稳态的维持与心肌细胞功能的正常运转密切相关。巨噬细胞可通过自噬与焦亡途径参与心肌损伤的修复过程,自噬有助于细胞的清除和炎症反应的调节,而焦亡则可通过释放炎症因子影响心肌修复。②中医药通过多种机制调节线粒体钙稳态和巨噬细胞功能,如黄芪甲苷通过降低线粒体膜电位和抑制细胞色素C来调节钙稳态,淫羊藿苷通过减少β-淀粉样蛋白沉积来发挥作用;中药复方和单味药物通过激活或抑制特定的信号通路,如PI3K/AKT、核因子κB等通路来促进心肌损伤的修复。③未来的研究应关注线粒体钙稳态、自噬与焦亡途径的相互作用,以及中药如何通过这些途径发挥治疗作用,为心肌损伤的治疗提供新的策略和药物。
