大兴安岭野生笃斯越桔逆转座子逆转录酶的多样性分析  

Diversity Analysis of Retrotransposon Reverse Transposases From Wild Blueberry Vaccinium uliginosum L. in Greater Khingan

作　　者：张文波[1] 白杨 余利敏[1] 伏鸿峰 闫伟[1] 

机构地区：[1]内蒙古农业大学林学院,内蒙古呼和浩特010019

出　　处：《北方园艺》2018年第4期41-48,共8页Northern Horticulture

基　　金：国家自然科学基金资助项目(31660213;31560065;31160143;31260168;31060106);内蒙古自然科学基金资助项目(2015MS0354);内蒙古农业大学博士基金资助项目(BJ08-27)

摘　　要：以大兴安岭野生笃斯越桔为试材,采用同源克隆技术分离了Ty3-Gypsy类逆转座子逆转录酶序列,研究了其同源性及系统进化关系,以期为分析笃斯越桔的遗传多样性,开发可靠的分子标记提供参考依据。结果表明:分离的19条序列(分别命名为VuGRE1~19)长度范围为376~418bp,同源性范围为23.3%~97.8%,显示出较高的异质性。氨基酸序列分析结果显示,分离的19条序列中有8条序列发生了不同程度的变异,其中终止密码子突变的频率最高;因此推测终止密码子突变可能是导致笃斯越桔逆转座子异质性的主要原因。系统进化分析结果显示,VuGRE1~19隶属于2个不同的基因家族。Family I仅包含3条序列,序列间的同源性较低,且与其它物种逆转录酶的遗传距离较远;说明Family I的起源较为古老,种的特异性较强。Family II包含16条序列,由3个Subfamily组成;各亚家族成员间的同源性较高,亲缘关系较近;说明该基因家族的活性较高。另外,Family II基因家族成员与其它物种的Ty3-Gypsy类逆转座子逆转录酶序列具有较高的同源性,特别是Subfamily 3与兴安落叶松、苹果、银杏、绿豆、荸荠等植物的逆转录酶具有较近的亲缘关系;说明这些成员在物种间存在广泛的横向交流。以上结果说明,Family II是笃斯越桔中广泛存在的逆转座子基因家族,并在笃斯越桔适应性遗传进化中发挥了重要作用。For analyzing genetic diversity and empoldering credible molecular marker of wild blueberry,Vaccinium uliginosum in Greater Khingan,reverse transposases of Ty3-Gypsy-like retrotransposons were isolated using homology based cloning techniques,and homology and phylogenetic relation were analyzed.The results revealed that the length of the nucleotide sequences of the 19 isolated sequences（named as VuGRE1-19）varied from 376 bp to 418 bp with homology ranged from 19.8%-97.8%,showing a high heterogeneity.Sequence analysis for the VuGRE1-19 showed that the stop code mutation with a high frequency occured in eight sequences,suggesting terminator mutation was the major reason resulted in heterogeneity of retrotransposons in V.uliginosum.Phylogenetic analysis showed that the 19 of sequences are consisted of two families,Family I contained only 3 sequences which showed low homology between each other,and far relationships with reverse transposases from the other plants,revealing ancient origin and low transcriptional activity.Family II contained 16 sequences,which consisted of 3 Subfamilies,the sequences of the Subfamilies show high similarity and close relationships between each other.The sequences of Subfamily 3 had a closer relationship with reverse transposases from the other plants,such as Malus pumila,Larix gmelinii,Peperomia caperata,Vigna radiate,Prunus salicina and Eleocharis dulcis,indicating extensive transfer of the subfamily members among different plant species.These results suggested that the Family II retrotransposons widespreadly existed in genome and played an important role in adaptive genetic evolution of the V.uliginosum.

关 键 词：笃斯越桔 逆转座子 逆转录酶 遗传多样性 

分 类 号：S663.901[农业科学—果树学]