蝎蝽次目线粒体基因组22个tRNA基因的比较研究(半翅目:异翅亚目)  

Comparative study of 22 mitochondrial tRNA genes in Nepomorpha (Hemiptera: Heteroptera)

作　　者：张丹丽 张苗苗 田菁 李悦锐 张虎芳 Zhang Danli;Zhang Miaomiao;Tian Jing;Li Yuerui;Zhang Hufang(Department of Biology, Taiyuan Normal University, Jinzhong 030619,China;Department of Biology, Xinzhou Normal University, Xinzhou 034000,China)

机构地区：[1]太原师范学院生物系,山西晋中030619 [2]忻州师范学院生物系,山西忻州034000

出　　处：《山西农业大学学报（自然科学版）》2019年第1期27-34,共8页Journal of Shanxi Agricultural University(Natural Science Edition)

基　　金：山西省来晋博士奖励科研启动基金(I170258);太原师范学院博士科研启动基金(I170174)

摘　　要：[目的]本研究旨在对蝎蝽次目11科线粒体基因组中22个tRNA基因的序列特征、遗传距离、同源基因相同核苷酸百分比和二级结构进行比较研究,同时基于22个tRNA序列构建蝎蝽次目的系统发育树。[方法]通过GenBank获得蝎蝽次目所有12个代表种的tRNA序列,在MEGA 6.0中计算tRNA基因序列特征和遗传距离,同源基因相同核苷酸百分比在BioEdit 7.1中进行,tRNA二级结构在RNA structure 5.8中构建。在RAxML 8.2.8和Mrbayes 3.2.5中构建系统发育树。[结果]结果显示蝎蝽次目11科核苷酸碱基组成(A+T)%平均含量为76.41%,碱基A和T的含量均高于G和C,其中多数种呈现A高于T,所有种呈现G高于C。蝎蝽次目11科间的遗传距离在0.13～0.26之间。核苷酸保守性较高的tRNA-L2、tRNA-T和tRNA-M基因均位于线粒体基因组的J链,核苷酸保守性较低的tRNA-V和tRNA-F基因均位于线粒体基因组的N链。蝎蝽次目11科内tRNA二级结构中氨基酸接受茎表现为较高的保守性,而环中除了反密码子环相对保守外,其余环都有不同程度的碱基变异。系统发育结果显示固蝽总科、仰泳蝽总科和划蝽总科均为单系,其中固蝽总科和仰泳蝽总科为姐妹群关系,其余总科的单系性没有得到很好的解析,可能与tRNA基因序列能够提供的有效系统发育信号较少有关。[结论]本研究补充了tRNA在蝎蝽次目研究中的不足,揭示了tRNA基因及其二级结构在比较线粒体基因组学研究中的重要性。[Objective]Present study was conducted to comparatively analyze the sequence character,genetic distance,percentage of identical nucleotides,and the secondary structure of 22 tRNA genes from 11 families of Nepomorpha and to construct phylogeny based on those determined gene informaiton.[Methods]All tRNA genes of 12 representative species of Nepomorpha were obtained from GenBank.Sequence character and genetic distance were computed in MEGA 6.0.Percentage of identical nucleotides was calculated in BioEdit 7.1.The secondary structure of tRNA genes were constructed in RNA structure 5.8,and phylogenetic trees were constructed in RAxML 8.2.8 and Mrbayes 3.2.5.[Results]The results showed that the average nucleotide composition of(A+T)%was 76.41%.The content of both A and T were higher than G and C,and A was higher than T in most species with G higher than C in all species.The genetic distance between inter-families was 0.13~0.26.The tRNA-L2,tRNA-T,and tRNA-M genes with higher nucleotide conservation were located in the major strand,and the tRNA-V and tRNA-F genes with low nucleotide conservation were located in the minority strand.The amino acid acceptor stem in the secondary structure showed a higher conservation,while the anticodon loops were relatively conservative and the other loops had different degrees of base variation.The phylogenetic results showed that Pleoidea,Notonectoidea,and Corixoidea were all monophyletic,and Pleoidea and Notonectoidea were sister groups.The monophyly of other superfamilies were not well received,which might be associated with less effective phylogenetic signals that tRNA gene sequences provided.[Conclusion]This study provided positive impact on knowledge gap of Nepomorpha tRNA and revealed the importance of tRNA gene and its secondary structure in comparative mitochondrial genomic study.

关 键 词：蝎蝽次目 线粒体基因组 TRNA 比较研究 系统发育 

分 类 号：S433.3[农业科学—农业昆虫与害虫防治]