SUMOylation attenuates c-Maf-dependent IL-4 expression
Journal
European journal of immunology
Journal Volume
40
Journal Issue
4
Pages
1174
Date Issued
2010-04
Author(s)
Lin, Bo-Shiou
Tsai, Pei-Yun
Hsieh, Wan-Yun
Tsao, Hsiao-Wei
Liu, Meng-Wei
Grenningloh, Roland
Ho, I-Cheng
Abstract
The function of transcription factors can be critically regulated by SUMOylation. c-Maf, the cellular counterpart of v-maf oncogene, is a potent transactivator of the IL-4 gene in Th2 cells. We found in a yeast two-hybrid screen that c-Maf can interact with Ubc9 and PIAS1, two key enzymes of the SUMOylation pathway. In this study, we report that c-Maf co-localized with these two SUMO (small ubiquitin-like modifier) ligases in the nucleus and that c-Maf can be SUMOylated in vitro and also in primary Th2 cells. We also demonstrated that lysine-33 is the dominant, if not the only, SUMO acceptor site of c-Maf. SUMOylation of c-Maf attenuated its transcriptional activity. Reciprocally, a SUMOylation resistant c-Maf was more potent than WT-c-Maf in driving IL-4 production in c-Maf-deficient Th2 cells. Furthermore, we showed that ablation of the SUMO site did not alter the subcellular localization or the stability of c-Maf protein but instead enhanced its recruitment to the Il4-promoter. We conclude that SUMOylation at lysine-33 is a functionally critical post-translational modification event of c-Maf in Th cells.
Subjects
c-Maf; Il4 Gene regulation; SUMOylation
Publisher
WILEY
Type
journal article