서울대학교 생물정보연구소와 생물정보학 협동과정 공동 주최로 특별 세미나를 아래와 같이 열고자 하오니, 많은 참여 바랍니다.

일시 : 2016년 9월 28일 수요일 오전 11시

연사 : 한규동 (단국대학교 나노바이오의과학과)

장소 : 서울대학교 25동 411호

TITLE : Retrotransposon mediated genomic variations in the human lineage

ABSTRACT : LINE-1s (Long interspersed elements or L1s) and Alus are highly successful non-long terminal repeat retrotansposons with copy numbers of ~520,000 and >1 million within the human genome, respectively. They are associated with human genetic variation and genomic rearrangement. Although they are abundant throughout primate genomes, their propagation strategy remains poorly understood. The recently released human and chimpanzee draft genome sequences provide the opportunity to compare the human genome with the chimpanzee genome. Thus, we were able to assess how these elements expanded in primate genomes and how they create genomic instability during their integration into the host genome as well as subsequent post-insertion recombination between elements. To understand the expansion of Alu elements, we first analyzed the evolutionary history of the AluYb lineage which is one of most active Alu lineages in the human genome. We suggest that the evolutionary success of Alu elements is driven at least in part by “stealth driver” elements that maintain low retrotransposition activity over extended periods of time and occasionally produce short-lived hyperactive copies responsible for the formation and remarkable expansion of Alu elements within the genome. Second, we conducted a detailed characterization of chimpanzee-specific L1 subfamily diversity. Our results showed that L1 elements have experienced different evolutionary fates in humans and chimpanzees lineages. These differential evolutionary paths may be the result of random variation or the product of competition between L1 subfamily lineages. Third, we report 50 deletion events in human and chimpanzee genomes directly linked to the insertion of L1 elements, resulting in the loss of ~18 kb of human genomic sequence and ~15 kb of chimpanzee genomic sequence. This study provides the basis for developing models of the mechanisms for small and large L1 insertion-mediated deletions. Fourth, we analyzed the magnitude of Alu recombination-mediated deletions in the human lineage subsequent to the human-chimpanzee divergence. We identified 492 human-specific deletions (for a total of ~400 kb of sequence) attributable to this process. The majority of the deletions coincide with known or predicted genes, which implicates this process in creating a substantial portion of the genomic differences between humans and chimpanzees.

EDUCATION :

Ph.D.　 　 　Biological Sciences, Louisiana State University 2006

M.S.　 　 　　Microbiology, Dankook University, Korea 2002

B.S.　 　 　 　Microbiology, Dankook University, Korea 2000

EMPLOYMENT :

AWARDS, MEMBERSHIP AND SERVICE :

Award of Excellent Scientists (given to 10 people) in Korea, 2007.

William H. Gates Award for Teaching Excellence, Louisiana State University, 2006.

ASM Travel Grant, MobileDNAConference,2006.

Vice Chancellor’s Graduate Enhancement, Louisiana State University, 2003-2006.

Associate Editor for Gene, Meta Gene, Genes & Genomics, Genomics & Informatics 2014-Present

Editor for The Open Access Journal of Science and Technology, 2013-Present

Guest Editor for Comparative and Functional Genomics, The Scientific World Journal

Reviewer (ad hoc) for Clinical Genetics, PLoS ONE, Genes & Genomics, Zoological Science, Analytical Biochemistry, Journal of Biomedical Science, Molecules & Cells, Genetica, Gene, Mobile DNA, Journal of Clinical Pathology

PUBLICATIONS : More than 70 SCI(E) papers including SCIENCE, PNAS, Genome Res etc.