446회 Implication of Staufen1-mediated mRNA decay in adipogenesis

446회 

연사:  김윤기 박사

제목 : Implication of Staufen1-mediated mRNA decay in adipogenesis

Abstract 

A double-stranded RNA binding protein Staufen1 (Stau1) is a multifunctional protein involved in a various cellular processes including mRNA decay, mRNA localization, and translation. For Staufen1-mediated mRNA decay (SMD), Stau1 recognizes and binds to a specific stem-loop structure in 3’ untranslated region (3’UTR) of target mRNA. After binding to mRNA, Stau1 recruits Upf1, which is known to be a key factor in nonsense-mediated mRNA decay (NMD), so as to trigger a rapid mRNA degradation. However, the downstream molecular events occurring after Upf1 recruitment remain unclear. Recently, we found that Stau1 recruits decapping complex via a protein interaction relay of Stau1-Upf1-PNRC2 (human proline-rich nuclear receptor coregulatory protein 2)-Dcp1a. We also found that Stau1 interacts with hyperphosphorylated Upf1 more strongly than wild-type Upf1. Intriguingly, Upf1 undergoes hyperphosphorylation during adipogenesis, the process of cellular differentialtion by which preadipocytes become adipocytes. Consistently, SMD efficiency increases during adipogenesis. The details for the underlying molecular mechanism and the possible implication of SMD in adipogenesis will be discussed. In addition, a molecular comparison between SMD and NMD will be discussed.