[대학원 생명과학과 세미나 안내]
연사 : 이강석 교수(중앙대학교 생명과학과)
연제 : Uncoventional regulation of gene expression by old ncRNAs
일시 : 2018년 10월 19일 (금) 오후 5시
장소 : 하나과학관 A동 B131호
초청교수 : 윤철원 교수
Abstract
Two examples of non-coding RNA-mediated regulation of gene expression that affect cellular pathophysiology will be presented.
Part I: Divergent rRNAs contribute to differential protein synthesis.
It is generally thought that each organism has evolved to possess a unique ribosomal RNA (rRNA) species that is optimal for its physiological needs; this assumption has provided the basis for the wide use of rRNA sequences as ‘evolutionary clock’. However, some organisms express heterogeneous rRNAs, of which functional role remains largely unknown. Here, we show that ribosomes containing the most variant rRNAs encoded by the rrnI operon mediate preferential translation of a subset of mRNAs and consequently modulate cellular physiology in Vibrio vulnificus CMCP6, which normally expresses 4-6 kinds of rRNAs in a cell. This study identifies divergent rRNAs as regulators in differential protein synthesis.
Part II: A miRNA targeting a coding mutation site induces haploinsufficiency of the tumour suppressor FOXL2
Animal microRNAs (miRNAs) are generally thought to act primarily on the 3′ untranslated region (UTR) of target mRNAs. However, growing evidence suggests that miRNAs can also act on sites in the coding sequence (CDS) of mRNAs, although the physiological relevance of these sites in normal and pathological contexts remains unclear. Here, we show that a somatic heterozygous missense mutation (c.402C>G; p.C134W) in the CDS of FOXL2, a feature shared by approximately 97% of adult-type granulosa cell tumors (AGCTs), introduces a target site for an miRNA, which induces haploinsufficiency of the tumor suppressor FOXL2. This study reveals a previously unsuspected mechanism of pathogenesis in which disease-associated missense mutations can cause miRNA-mediated mRNA degradation.