The conserved DNA damage repair complex,MMS21-SMC5/6(Methyl methane sulfonate 21-Structural maintenance of chromosomes 5/6),has been extensively studied in yeast,animals,and plants.However,its role in phytopathogenic ...The conserved DNA damage repair complex,MMS21-SMC5/6(Methyl methane sulfonate 21-Structural maintenance of chromosomes 5/6),has been extensively studied in yeast,animals,and plants.However,its role in phytopathogenic fungi,particularly in the highly destructive rice blast fungus Magnaporthe oryzae,remains unknown.In this study,we functionally characterized the homologues of this complex,MoMMS21 and MoSMC5,in M.oryzae.We first demonstrated the importance of DNA damage repair in M.oryzae by showing that the DNA damage inducer phleomycin inhibited vegetative growth,infection-related development and pathogenicity in this fungus.Additionally,we discovered that MoMMS21 and MoSMC5 interacted in the nuclei,suggesting that they also function as a complex in M.oryzae.Gene deletion experiments revealed that both MoMMS21 and MoSMC5 are required for infection-related development and pathogenicity in M.oryzae,while only MoMMS21 deletion affected growth and sensitivity to phleomycin,indicating its specific involvement in DNA damage repair.Overall,our results provide insights into the roles of MoMMS21 and MoSMC5 in M.oryzae,highlighting their functions beyond DNA damage repair.展开更多
真核生物基因组DNA主要以染色体的形式存在于细胞核中,染色体结构的稳定及其动态变化对于真核生物遗传信息从亲代到子代中的准确传递和维持细胞的正常功能是必不可少的。染色体结构维持蛋白(Structure Maintenance of Chromosome, Smc)...真核生物基因组DNA主要以染色体的形式存在于细胞核中,染色体结构的稳定及其动态变化对于真核生物遗传信息从亲代到子代中的准确传递和维持细胞的正常功能是必不可少的。染色体结构维持蛋白(Structure Maintenance of Chromosome, Smc)在染色体结构维持及DNA损伤修复方面发挥着关键性的作用。Smc蛋白家族包括3类:黏连蛋白(Cohesin)、凝缩蛋白(Condesin)和Smc5/6复合体(Smc5/6 complex)。Smc5/6复合体在真核生物中分布广泛且高度保守,在DNA损伤同源重组修复、DNA复制、端粒长度维持及胚胎发育中发挥重要作用。本文系统介绍了Smc5/6复合体结构特征和生物学功能领域的相关进展,为深入研究Smc5/6复合体提供理论参考。展开更多
染色体不仅仅由DNA构成,还包含一些使染色体能具有特定形态特征以及在基因表达和基因组稳定性中起作用的蛋白。而使染色体能具有特定形态特征的首要物质就是染色体结构维持蛋白(structural maintenance of chromosomes,SMC)复合体。SMC...染色体不仅仅由DNA构成,还包含一些使染色体能具有特定形态特征以及在基因表达和基因组稳定性中起作用的蛋白。而使染色体能具有特定形态特征的首要物质就是染色体结构维持蛋白(structural maintenance of chromosomes,SMC)复合体。SMC复合体包含凝聚蛋白(condensin)、黏结蛋白(cohesin)和SMC5-SMC6复合体,是染色体的重要组分。SMC蛋白的表达依赖于ATP的水解以及DNA的拓扑作用。SMC复合体参与了多重染色体行为,其中尤为显著的是染色体集缩和姐妹染色单体的黏着。此外,SMC复合体在DNA修复中也有重要的作用。近年来,随着分子生物学研究技术的发展,对该类复合体的结构、功能及作用机制等方面已有较多研究并取得一些重要进展,本文对SMC蛋白结构和功能的研究进展做一综述。展开更多
Hepatitis B virus(HBV) is still a worldwide health concern. While divergent factors are involved in its pathogenesis, it is now clear that HBV RNAs, principally templates for viral proteins and viral DNAs, have divers...Hepatitis B virus(HBV) is still a worldwide health concern. While divergent factors are involved in its pathogenesis, it is now clear that HBV RNAs, principally templates for viral proteins and viral DNAs, have diverse biological functions involved in HBV pathogenesis. These functions include viral replication, hepatic fibrosis and hepatocarcinogenesis. Depending on the sequence similarities, HBV RNAs may act as sponges for host mi RNAs and may deregulate mi RNA functions, possibly leading to pathological consequences. Some parts of the HBV RNA molecule may function as viralderived mi RNA, which regulates viral replication. HBV DNA can integrate into the host genomic DNA and produce novel viral-host fusion RNA, which may have pathological functions. To date, elimination of HBVderived covalently closed circular DNA has not been achieved. However, RNA transcription silencing may be an alternative practical approach to treat HBVinduced pathogenesis. A full understanding of HBV RNA transcription and the biological functions of HBV RNA may open a new avenue for the development of novel HBV therapeutics.展开更多
基金Research and Development Program of China(2023YFD1400200)the Natural Science Foundation of Fujian Province,China(2022J01125)+2 种基金the Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests,China(MIMCP-202301)the Fujian Provincial Science and Technology Key Project,China(2022NZ030014)the National Natural Science Foundation of China(NSFC31871914).
文摘The conserved DNA damage repair complex,MMS21-SMC5/6(Methyl methane sulfonate 21-Structural maintenance of chromosomes 5/6),has been extensively studied in yeast,animals,and plants.However,its role in phytopathogenic fungi,particularly in the highly destructive rice blast fungus Magnaporthe oryzae,remains unknown.In this study,we functionally characterized the homologues of this complex,MoMMS21 and MoSMC5,in M.oryzae.We first demonstrated the importance of DNA damage repair in M.oryzae by showing that the DNA damage inducer phleomycin inhibited vegetative growth,infection-related development and pathogenicity in this fungus.Additionally,we discovered that MoMMS21 and MoSMC5 interacted in the nuclei,suggesting that they also function as a complex in M.oryzae.Gene deletion experiments revealed that both MoMMS21 and MoSMC5 are required for infection-related development and pathogenicity in M.oryzae,while only MoMMS21 deletion affected growth and sensitivity to phleomycin,indicating its specific involvement in DNA damage repair.Overall,our results provide insights into the roles of MoMMS21 and MoSMC5 in M.oryzae,highlighting their functions beyond DNA damage repair.
文摘染色体不仅仅由DNA构成,还包含一些使染色体能具有特定形态特征以及在基因表达和基因组稳定性中起作用的蛋白。而使染色体能具有特定形态特征的首要物质就是染色体结构维持蛋白(structural maintenance of chromosomes,SMC)复合体。SMC复合体包含凝聚蛋白(condensin)、黏结蛋白(cohesin)和SMC5-SMC6复合体,是染色体的重要组分。SMC蛋白的表达依赖于ATP的水解以及DNA的拓扑作用。SMC复合体参与了多重染色体行为,其中尤为显著的是染色体集缩和姐妹染色单体的黏着。此外,SMC复合体在DNA修复中也有重要的作用。近年来,随着分子生物学研究技术的发展,对该类复合体的结构、功能及作用机制等方面已有较多研究并取得一些重要进展,本文对SMC蛋白结构和功能的研究进展做一综述。
基金Supported by the Research Program on Hepatitis from Japan Agency for Medical Research and Development,AMED to Otsuka M,No.JP18fk0210214the Project for Cancer Research and Therapeutic Evolution(P-CREATE)from AMED to Otsuka M,No.JP19cm0106602
文摘Hepatitis B virus(HBV) is still a worldwide health concern. While divergent factors are involved in its pathogenesis, it is now clear that HBV RNAs, principally templates for viral proteins and viral DNAs, have diverse biological functions involved in HBV pathogenesis. These functions include viral replication, hepatic fibrosis and hepatocarcinogenesis. Depending on the sequence similarities, HBV RNAs may act as sponges for host mi RNAs and may deregulate mi RNA functions, possibly leading to pathological consequences. Some parts of the HBV RNA molecule may function as viralderived mi RNA, which regulates viral replication. HBV DNA can integrate into the host genomic DNA and produce novel viral-host fusion RNA, which may have pathological functions. To date, elimination of HBVderived covalently closed circular DNA has not been achieved. However, RNA transcription silencing may be an alternative practical approach to treat HBVinduced pathogenesis. A full understanding of HBV RNA transcription and the biological functions of HBV RNA may open a new avenue for the development of novel HBV therapeutics.
