Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
EMBO Rep. 2005 Nov;6(11):1082-7. Epub 2005 Sep 23.

The RING-finger scaffold protein Plenty of SH3s targets TAK1 to control immunity signalling in Drosophila.

Author information

  • 1Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji-shi, Tokyo 192-0397, Japan.

Abstract

Imd-mediated innate immunity is activated in response to infection by Gram-negative bacteria and leads to the activation of Jun amino-terminal kinase (JNK) and Relish, a nuclear factor-kappaB transcription factor responsible for the expression of antimicrobial peptides. Plenty of SH3s (POSH) has been shown to function as a scaffold protein for JNK activation, leading to apoptosis in mammals. Here, we report that POSH controls Imd-mediated immunity signalling in Drosophila. In POSH-deficient flies, JNK activation and Relish induction were delayed and sustained, which indicated that POSH is required for properly timed activation and termination of the cascade. The RING finger of POSH, possessing ubiquitin-ligase activity, was essential for termination of JNK activation. We show that POSH binds to and degrades TAK1, a crucial activator of both the JNK and the Relish signalling pathways. These results establish a novel role for POSH in the Drosophila immune system.

PMID:
16179944
[PubMed - indexed for MEDLINE]
PMCID:
PMC1371032
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk