池蝶蚌线粒体基因组双单性遗传现象分析  

Doubly Uniparental Inheritance Analysis of Mitochondrial Genome in Hyriopsis schlegelii

作　　者：盛军庆[1] 林巧惠[1] 王军花[1] 彭扣[1] 曾柳根[1,2] 洪一江[1] 

机构地区：[1]南昌大学生命科学与食品工程学院,南昌330031 [2]南昌市农业科学院,南昌330038

出　　处：《动物学杂志》2014年第4期597-604,共8页Chinese Journal of Zoology

基　　金：国家公益性行业科研专项(No.200903028);国家自然科学基金项目(No.31160534);江西省科技落地计划项目(No.KJLD12001);江西省自然科学基金项目(No.20122BAB204016)

摘　　要：部分双壳贝类的线粒体遗传方式不同于标准的母系遗传(SMI),被称为双单性遗传现象(DUI)。池蝶蚌(Hyriopsis schlegelii)是淡水双壳贝类,是否存在双单性遗传现象?本文采用普通PCR扩增、SHOT-GUN测序及软件拼接获得了雄性池蝶蚌线粒体基因组(以下简称Hs-mtDNA)全序列,并与本实验室已报道的雌性池蝶蚌线粒体基因组全序列进行差异性分析。结果表明,雄性和雌性Hs-mtDNA全长分别为15961 bp和15939 bp,雄性比雌性长22 bp,雌雄线粒体基因组成与排列顺序一致。各蛋白编码基因的碱基数目均一致,碱基转换率为1.01%～7.34%,颠换率为0.00%～0.62%,氨基酸差异率为0.00%～9.35%;其中,COX1基因变异率为2.72%;COX2基因碱基变异率最高,达7.50%,雄性COX2的3'末端没有出现编码延伸区。雄性12S rRNA基因发生5 bp的碱基转换,差异率为0.6%;16S rRNA基因比雌性长9 bp,碱基差异率仅为1.2%。雌雄tRNA-His均位于H链上,介于COX2与ND3之间,没有出现位置的差异性。雌雄Hs-mtDNA的非编码区共有28个1～393 bp的片段,但未见控制区。在tRNA-Glu与tRNA-Tyr间有一段长393 bp的非编码区存在蛋白质翻译功能,但非雄性特异性蛋白。以COX1基因建立系统进化树,池蝶蚌和三角帆蚌(H.cumingii)聚在一起,而含有双单性遗传现象的无齿蚌属的Pyganodon grandis、小方蚌亚科的Venustaconcha ellipsiformis及小方形蚌属的Quadrula quadrula三者雄性聚为一支,雌性聚为一支。因此,雌雄池蝶蚌线粒体存在一定的差异性,但其差异要比其他具有双单性遗传现象的淡水双壳类小得多,且池蝶蚌线粒体遗传可能不存在双单性遗传现象。Mitochondrial inheritance mode of some bivalves is different from standard mitochondrial inheritance（ SMI）,which is named doubly uniparental inheritance（ DUI）. Hyriopsis schlegelii is a freshwater bivalve,but whether it shows DUI is not known. The paper researched the complete mitochondrial genome of male H.schlegelii using PCR, shot-gun sequencing technology, and analyzed DUI of mitochondrial genome of H. schlegelii according to the mtDNA characteristics,protein-coding genes,tRNA-His gene and the difference of non-coding region of male and female H. schlegelii. The results showed that the mitochondrial genome sequences of male and female contained 15 961 and 15 939 base pairs,respectively. Two mtDNA sequences contained identical genetic constitution and gene arrangement including 13 protein-coding genes,22 transfer RNA genes,2 ribosomal RNA genes,and 28 non-coding regions ranged from 1 to 393 bp in size. When comparing the protein-coding genes of two sequences,there was no difference in sequence length,and the ratio of transition and transversion,and amino acid differences were 1. 01%- 7. 34%,0. 00%- 0. 62% and0. 00%- 9. 35%,respectively. There was 2. 72% transition and transversion of COX1 and 7. 50% of COX2 between the male and female. There was no extra male sequence of a 3’ C-terminus codon extension of COX2.12 S rRNA gene of male contained 5 bp transition and the ratio was only 0. 6%; 16 S rRNA of male was 9 bp longer than that of female and the transition ratio was 1. 2%. The location of tRNA-His was the same between the male and female,which was encoded on the H strand and was located between COX2 and ND3. There was no control region in non-coding regions. There were identical potential polypeptides in the non-coding regions between tRNA-Glu and tRNA-Tyr of the male and female, which were not the male-specific proteins.Constructing a molecular phylogenetic tree based on COX1 genes using neighbor-joining methods（ MEGA 4. 0software）,it was showed that H. schlegelii and H. cumingii had the clos

关 键 词：池蝶蚌 线粒体基因组 差异性分析 双单性遗传 

分 类 号：Q75[生物学—分子生物学]