旨在从基因组层面揭示梅花鹿与欧洲马鹿的起源进化,找到与进化过程相关的信号通路并与表型进行关联。本试验以成年雌性梅花鹿与成年雄性欧洲马鹿染色体水平基因组作为研究对象,利用比较基因组学的方法对梅花鹿和欧洲马鹿基因组进行染色...旨在从基因组层面揭示梅花鹿与欧洲马鹿的起源进化,找到与进化过程相关的信号通路并与表型进行关联。本试验以成年雌性梅花鹿与成年雄性欧洲马鹿染色体水平基因组作为研究对象,利用比较基因组学的方法对梅花鹿和欧洲马鹿基因组进行染色体共线性分析,获得两个物种间基因组序列的同源关系和基因组发生的染色体倒位现象,并对被倒位截断和在倒位内部未被截断的两类基因分别进行GO和KEGG功能富集分析;同时对两个物种染色体上的基因进行共线性分析,识别二者基因组间的直系同源区域,检测直系同源基因,估算两个物种的分化时间。结果显示,梅花鹿与欧洲马鹿基因组表现出同源性,有27条染色体的同源性在95%以上;通过基因组的比对确定了梅花鹿的23号染色体是X染色体;而对染色体倒位的统计及基因的GO和KEGG功能富集分析发现,梅花鹿基因组共有37847个倒位,片段长度为1~5 kb的倒位数目最多;而倒位涉及基因的GO功能富集的生物学过程及分子功能有嗅觉中化学刺激的检测、嗅觉感觉、嗅觉感受器活动、信号传感器活动;KEGG富集的是嗅觉传导信号通路。而梅花鹿与欧洲马鹿基因共线性分析共检测出79个同源区段,12629个直系同源基因,利用同源基因的同义突变率(Ks)估算出梅花鹿与欧洲马鹿的分化时间是0.318 MYA(millions of years ago)。本研究利用比较基因组学的方法,获得了梅花鹿与欧洲马鹿基因组间的同源关系以及两个物种染色体倒位现象,通过功能富集分析发现,染色体倒位与嗅觉表型有关,为鹿属动物染色体进化的研究提供新的理论基础。展开更多
For the past several years, a novel dwarf disease has been observed on rice (Oryza sativa) in some regions of Guangdong Province and Hainan Province, southern China. Infected plants showed stunting, dark leaf and smal...For the past several years, a novel dwarf disease has been observed on rice (Oryza sativa) in some regions of Guangdong Province and Hainan Province, southern China. Infected plants showed stunting, dark leaf and small enations on stem and leaf back. Typical Fijivirus viroplasma containing crystalline arrayed spherical virons approximately 70―75 nm in diameter and tubular structures were detected in ultrathin sections by an electron microscope in parenchyma phloem cells of the infected plants. The virus was transmitted to rice seedlings by white-backed planthoppers, Sogatella furcifera (Hemiptera: Delphacidae), collected in the diseased fields. Analysis of dsRNA extracts from infected plants revealed ten linear segments, which were similar to the electrophoretic profile of Rice black-streaked dwarf virus (RBSDV). RT-PCR with a single primer which matched to a linker sequence ligated to both 3′ ends of the viral genomic dsRNAs resulted in amplification of genome segments 9 (S9) and 10 (S10) cDNA products. The complete nucleotide sequences of S9 and S10 were obtained from clones of the RT-PCR amplicon exhibited characteristic properties of Fijivirus including low GC content (34.5% and 35.6%), genus conserved 5′ and 3′ termini sequences and similar genome organization. Blast searches indicated that the sequences of S9 and S10 shared 68.8%―74.9% and 67.1%―77.4% nucleotide identities with those of viruses in the Fijivirus group 2, respectively. These values were similar to those among other viruses in the Fijivirus group 2 and considerably lower than those among RBSDV isolates. Phylogenetic trees based on S9 and S10 nucleotide sequences and their putative amino acid sequences showed that this virus represented a separate branch among other Fijiviruses. The virus was also detected by a nested RT-PCR assay in corn (Zea mays), barnyard grass (Echinochloa crusgalli), Juncellus serotinus and flaccidgrass (Pennisetum flaccidum) in and/or adjacent to the infected rice fields. It is proposed that this virus be considered as a new species, Southern rice black-streaked dwarf virus, in the group 2 of the genus Fijivirus in the family Reoviridae.展开更多
文摘旨在从基因组层面揭示梅花鹿与欧洲马鹿的起源进化,找到与进化过程相关的信号通路并与表型进行关联。本试验以成年雌性梅花鹿与成年雄性欧洲马鹿染色体水平基因组作为研究对象,利用比较基因组学的方法对梅花鹿和欧洲马鹿基因组进行染色体共线性分析,获得两个物种间基因组序列的同源关系和基因组发生的染色体倒位现象,并对被倒位截断和在倒位内部未被截断的两类基因分别进行GO和KEGG功能富集分析;同时对两个物种染色体上的基因进行共线性分析,识别二者基因组间的直系同源区域,检测直系同源基因,估算两个物种的分化时间。结果显示,梅花鹿与欧洲马鹿基因组表现出同源性,有27条染色体的同源性在95%以上;通过基因组的比对确定了梅花鹿的23号染色体是X染色体;而对染色体倒位的统计及基因的GO和KEGG功能富集分析发现,梅花鹿基因组共有37847个倒位,片段长度为1~5 kb的倒位数目最多;而倒位涉及基因的GO功能富集的生物学过程及分子功能有嗅觉中化学刺激的检测、嗅觉感觉、嗅觉感受器活动、信号传感器活动;KEGG富集的是嗅觉传导信号通路。而梅花鹿与欧洲马鹿基因共线性分析共检测出79个同源区段,12629个直系同源基因,利用同源基因的同义突变率(Ks)估算出梅花鹿与欧洲马鹿的分化时间是0.318 MYA(millions of years ago)。本研究利用比较基因组学的方法,获得了梅花鹿与欧洲马鹿基因组间的同源关系以及两个物种染色体倒位现象,通过功能富集分析发现,染色体倒位与嗅觉表型有关,为鹿属动物染色体进化的研究提供新的理论基础。
基金the Guangdong Provincial Department of Science and Technology (Grant No. 2003B21604)Natural Science Foundation of Guandong Province (Grant No. 5006669)Agricultural Department of Hainan Province
文摘For the past several years, a novel dwarf disease has been observed on rice (Oryza sativa) in some regions of Guangdong Province and Hainan Province, southern China. Infected plants showed stunting, dark leaf and small enations on stem and leaf back. Typical Fijivirus viroplasma containing crystalline arrayed spherical virons approximately 70―75 nm in diameter and tubular structures were detected in ultrathin sections by an electron microscope in parenchyma phloem cells of the infected plants. The virus was transmitted to rice seedlings by white-backed planthoppers, Sogatella furcifera (Hemiptera: Delphacidae), collected in the diseased fields. Analysis of dsRNA extracts from infected plants revealed ten linear segments, which were similar to the electrophoretic profile of Rice black-streaked dwarf virus (RBSDV). RT-PCR with a single primer which matched to a linker sequence ligated to both 3′ ends of the viral genomic dsRNAs resulted in amplification of genome segments 9 (S9) and 10 (S10) cDNA products. The complete nucleotide sequences of S9 and S10 were obtained from clones of the RT-PCR amplicon exhibited characteristic properties of Fijivirus including low GC content (34.5% and 35.6%), genus conserved 5′ and 3′ termini sequences and similar genome organization. Blast searches indicated that the sequences of S9 and S10 shared 68.8%―74.9% and 67.1%―77.4% nucleotide identities with those of viruses in the Fijivirus group 2, respectively. These values were similar to those among other viruses in the Fijivirus group 2 and considerably lower than those among RBSDV isolates. Phylogenetic trees based on S9 and S10 nucleotide sequences and their putative amino acid sequences showed that this virus represented a separate branch among other Fijiviruses. The virus was also detected by a nested RT-PCR assay in corn (Zea mays), barnyard grass (Echinochloa crusgalli), Juncellus serotinus and flaccidgrass (Pennisetum flaccidum) in and/or adjacent to the infected rice fields. It is proposed that this virus be considered as a new species, Southern rice black-streaked dwarf virus, in the group 2 of the genus Fijivirus in the family Reoviridae.
