[대학원 생명과학과 세미나 안내]
연사 : 온탁범 교수 (조선대학교 의학과)
연제 : NEDDylation promotes stress granule assembly
일시 : 2016년 6월 10일 (금) 오후 4시
장소 : 하나과학관 A동 109호
초청교수 : 김윤기 교수
Abstract
Stress granules (SGs) harbor translationally stalled mRNPs and play important roles in regulating gene expression and cell fate. The cellular signaling pathways that lead to SG assembly are incompletely understood. Here we show that neddylation promotes SG assembly in response to arsenite-induced oxidative stress. Inhibition or depletion of key components of the neddylation machinery concomitantly inhibits stress-induced polysome disassembly and SG assembly. Affinity purification and subsequent mass-spectrometric analysis of Nedd8-conjugated proteins from translationally stalled ribosomal fractions identifies ribosomal proteins, translation factors and RNA-binding proteins (RBPs), including SRSF3, a previously identified SG regulator. We show that SRSF3 is selectively neddylated at Lys 85 in response to arsenite. Cells expressing a non-neddylatable SRSF3 (K85R) mutant do not affect arsenite-induced polysome disassembly, but are unable to support the SG assembly. Our observations suggest that the neddylation pathway plays an important role in the SG assembly.