Persistent tapetal cell1(PTC1) plays a curial role in pollen development, and is thought to function as a transcriptional activator in rice. However, the molecular mechanism of PTC1 in regulating pollen development an...Persistent tapetal cell1(PTC1) plays a curial role in pollen development, and is thought to function as a transcriptional activator in rice. However, the molecular mechanism of PTC1 in regulating pollen development and its cis-elements are not well understood. We identified a novel weak male sterility mutant(ms92) which exhibited expanded tapetum and shrink pollen grains. Map-based cloning and allelic analysis suggested that the male sterility of ms92 was caused by a DNA fragment substitution in the promoter of PTC1. The decreased expression of MS92/PTC1 in ms92 and cis-element analysis indicated that the substituted sequence contained several potential binding cis-element of negative feedback. MS92/PTC1 was specifically expressed in tapetum and microspores at the young microspore stage, and its protein was localized in nucleus. We further found that MS92/PTC1 functions as a transcription activator by recognizing H3K4me3. Transcriptomic analysis revealed that a number of genes involved in tapetum degeneration and pollen wall formation were down-regulated in ms92, which are the potential targets of MS92/PTC1. The substitution fragment in MS92/PTC1 promoter was essential for pollen development, and we provided a novel mutant for further identifying the cis-elements in promoter and the molecular network of MS92/PTC1.展开更多
【目的】通过NaCl胁迫下哈茨木霉(Trichoderma harzianum)ACCC32527差异转录组和代谢组数据分析,挖掘关键功能型差异表达基因(DEG)及次级代谢产物。【方法】采用RNAseq和GCTOFMS技术分别完成0(T1)、0.4(T2)、0.6(T3)mol·L^-1NaCl...【目的】通过NaCl胁迫下哈茨木霉(Trichoderma harzianum)ACCC32527差异转录组和代谢组数据分析,挖掘关键功能型差异表达基因(DEG)及次级代谢产物。【方法】采用RNAseq和GCTOFMS技术分别完成0(T1)、0.4(T2)、0.6(T3)mol·L^-1NaCl胁迫下哈茨木霉ACCC32527的差异表达基因和次级代谢产物检测,利用相关软件及数据库(GO、COG、KEGG pathway等)完成对差异表达基因(|log2fold change)|>1&FDR<0.01)和次级代谢产物(P-value≤0.05&VIP>1)的筛选、注释和分类,并进行RTqPCR验证。【结果】NaCl胁迫处理后,ACCC32527的生长受到抑制,繁殖速率明显降低,并在该条件下分别获得T1 vs T2和T1 vs T3比较组637、1570个DEG,获得DEG的16种表达模式,包括9种上调表达模式(950gene)、3种下调表达模式(662gene)和4种不规则表达模式(309gene),共有的GO功能分类为催化活性、结合、细胞器、细胞膜部分、细胞膜、细胞部分、细胞、单组织过程和代谢过程,且占主要比例,约为61%—94%,其中处理前后基因比例差异较大的分类为催化活性。KEGG代谢通路富集分析发现,不同NaCl浓度处理下的DEG富集到的代谢通路种类及数量存在较大差异,分别有225和535个差异基因富集于20条KEGG通路,包括代谢通路、抗生素的合成和次级代谢产物合成,其中T2和T3处理下核糖体的生物合成途径分别有12个和18个相关基因受到抑制。从NaCl胁迫下差异转录组中筛选出活性氧清除、离子转运和细胞壁及胞外结构等共73个相关基因,并且多数为上调表达基因。另外,差异代谢组学分析表明,T3处理下,胞内小分子代谢物出现明显变化,累积量增加的代谢产物有30种,包括氨基酸及其衍生物、糖类及其衍生物和醇类,而减少的代谢物有53种,涉及脂肪酸和有机酸等。其中,甘油是已知的真菌重要渗透保护物,T3处理下ACCC32527胞内甘油水平提高,可参与细胞的渗透调节,维持渗透压平衡。RTqPCR验证了7个差异表达显著基因,虽然在表达量上存在一定的差异,但表达趋势与RNAseq分析结果基本一致,表明转录组测序结果的可靠性。【结论】NaCl胁迫引起哈茨木霉ACCC32527大量基因及次级代谢产物变化,获得了与NaCl胁迫调节相关基因和代谢产物,这些机制共同作用减少盐离子对细胞的毒害作用,研究结果可为研究木霉菌的耐盐机理提供重要信息。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31301054)。
文摘Persistent tapetal cell1(PTC1) plays a curial role in pollen development, and is thought to function as a transcriptional activator in rice. However, the molecular mechanism of PTC1 in regulating pollen development and its cis-elements are not well understood. We identified a novel weak male sterility mutant(ms92) which exhibited expanded tapetum and shrink pollen grains. Map-based cloning and allelic analysis suggested that the male sterility of ms92 was caused by a DNA fragment substitution in the promoter of PTC1. The decreased expression of MS92/PTC1 in ms92 and cis-element analysis indicated that the substituted sequence contained several potential binding cis-element of negative feedback. MS92/PTC1 was specifically expressed in tapetum and microspores at the young microspore stage, and its protein was localized in nucleus. We further found that MS92/PTC1 functions as a transcription activator by recognizing H3K4me3. Transcriptomic analysis revealed that a number of genes involved in tapetum degeneration and pollen wall formation were down-regulated in ms92, which are the potential targets of MS92/PTC1. The substitution fragment in MS92/PTC1 promoter was essential for pollen development, and we provided a novel mutant for further identifying the cis-elements in promoter and the molecular network of MS92/PTC1.
文摘【目的】通过NaCl胁迫下哈茨木霉(Trichoderma harzianum)ACCC32527差异转录组和代谢组数据分析,挖掘关键功能型差异表达基因(DEG)及次级代谢产物。【方法】采用RNAseq和GCTOFMS技术分别完成0(T1)、0.4(T2)、0.6(T3)mol·L^-1NaCl胁迫下哈茨木霉ACCC32527的差异表达基因和次级代谢产物检测,利用相关软件及数据库(GO、COG、KEGG pathway等)完成对差异表达基因(|log2fold change)|>1&FDR<0.01)和次级代谢产物(P-value≤0.05&VIP>1)的筛选、注释和分类,并进行RTqPCR验证。【结果】NaCl胁迫处理后,ACCC32527的生长受到抑制,繁殖速率明显降低,并在该条件下分别获得T1 vs T2和T1 vs T3比较组637、1570个DEG,获得DEG的16种表达模式,包括9种上调表达模式(950gene)、3种下调表达模式(662gene)和4种不规则表达模式(309gene),共有的GO功能分类为催化活性、结合、细胞器、细胞膜部分、细胞膜、细胞部分、细胞、单组织过程和代谢过程,且占主要比例,约为61%—94%,其中处理前后基因比例差异较大的分类为催化活性。KEGG代谢通路富集分析发现,不同NaCl浓度处理下的DEG富集到的代谢通路种类及数量存在较大差异,分别有225和535个差异基因富集于20条KEGG通路,包括代谢通路、抗生素的合成和次级代谢产物合成,其中T2和T3处理下核糖体的生物合成途径分别有12个和18个相关基因受到抑制。从NaCl胁迫下差异转录组中筛选出活性氧清除、离子转运和细胞壁及胞外结构等共73个相关基因,并且多数为上调表达基因。另外,差异代谢组学分析表明,T3处理下,胞内小分子代谢物出现明显变化,累积量增加的代谢产物有30种,包括氨基酸及其衍生物、糖类及其衍生物和醇类,而减少的代谢物有53种,涉及脂肪酸和有机酸等。其中,甘油是已知的真菌重要渗透保护物,T3处理下ACCC32527胞内甘油水平提高,可参与细胞的渗透调节,维持渗透压平衡。RTqPCR验证了7个差异表达显著基因,虽然在表达量上存在一定的差异,但表达趋势与RNAseq分析结果基本一致,表明转录组测序结果的可靠性。【结论】NaCl胁迫引起哈茨木霉ACCC32527大量基因及次级代谢产物变化,获得了与NaCl胁迫调节相关基因和代谢产物,这些机制共同作用减少盐离子对细胞的毒害作用,研究结果可为研究木霉菌的耐盐机理提供重要信息。
