Transposons, a Selfish Friend in Mammalian Preimplantation Development

Thursday, March 21, 2024 | 12:00 to 1:00 p.m. ET

Lin He, Ph.D.

Professor Dept of Molecular & Cell Biology

University of California, Berkeley

lhe@berkeley.edu

Website

Lin He is a professor in molecular & cell biology and UC Berkeley with research interests in the functional importance of the non-coding genome. The number of protein-coding genes clearly fails to correlate with the developmental and pathological complexity in mammals. Her research group's overall research interest is to understand the unique biological functions and molecular regulation of various non-coding RNAs and transposable elements in development and disease. Her group aims to understand the distinct biological functions and molecular regulation conferred by miRNAs, long ncRNAs and retrotransposons in development and disease using an interdisciplinary approach combining mouse genetics, genomics, imaging studies, cell biology, and molecular biology. Their studies have provided important insights on the fundamental molecular mechanisms that govern the unique functional complexity of the non-coding genome.

Summary

https://videocast.nih.gov/watch=51131

Since the discovery of transposons, their sheer abundance in host genomes has puzzled many. While historically viewed as largely harmless 'parasitic' DNAs during evolution, transposons are not a mere record of ancient genome invasion. Instead, nearly every element of transposon biology has been integrated into host biology. My lab has discovered cell-type and context-dependent expression of many retrotransposon-derived transcripts in preimplantation embryos, and characterized their biological significance. Many retrotransposon elements, upon reactivation, can provide alternative promoter, cause alternative splicing, or generate alternative polyadenylation signals to the proximal protein coding genes. Thus, these parasitic sequences in the mammalian genome can be exploited by the host genome to impose gene regulatory functions during defined developmental and pathological contexts. Hence, genome sequences introduced by transposon activities provide raw material for genome innovation and document the distinct evolutionary path of each species.

Presentation Objectives:

1. The regulation of transposons in preimplantation development
2. The role of transposon-dependent gene regulation in preimplantation development
3. The role of transposon encoded proteins in preimplantation development