报告题目：Retrotransposons and genome evolution

报告人：Prof. David Adelson

报告时间：9月16日上午10:00-11:30

报告地点：闵行校区生命科学技术学院3号楼105会议室

联系人：　韦朝春 This e-mail address is being protected from spambots. You need JavaScript enabled to view it.

 

报告摘要：

We have carried out comprehensive genome analyses of repetitive DNA sequences, including retrotransposons in 10 species: human, mouse, rat, horse, cow, sheep, dog, elephant, opossum and platypus.  In addition, we have carried out characterisation of specific non-LTR retrotransposon sequences (BovB and LINE L1) in all publicly available metazoan sequence data.  Our data indicate that horizontal transfer (HT) of BovB is much more widespread in animals than previously believed, supporting a significant role for HT in genome evolution of higher organisms.  We have also found that the ancestral, LINE L2 retrotransposos and their derived SINE Mirs - inactive in eutheria and marsupials - have persisted in conserved regions of shared synteny.  Other recently derived (clade specific) SINEs or horizontally transferred BovB tend to accumulate more outside of these regions, hinting that these regions are resistant to incursion of currently active or horizontally transferred.  Finally, we have also examined the prevalence and “intactness” of LINE L1 retrotransposons in all publicly available animal genome sequences.  L1 elements are believed to be ancestrally derived and currently retrotranspositionally active in most genomes.  Our data however, indicate that in the genomes of many species with high L1 content, no L1s with intact and potentially functional open reading frames (ORFs) exist.  This suggests that in many species with inactive L1s along with their derived SINEs, there is a lower potential for new genetic diversity associated with retrotransposition. This has implications both for evolution and for the incidence of diseases stemming from somatic retrotransposition.