beta-Arrestins facilitate ubiquitin-dependent degradation of apoptosis signal-regulating kinase 1 (ASK1) and attenuate H2O2-induced apoptosis

Cell Signal. 2009 Jul;21(7):1195-206. doi: 10.1016/j.cellsig.2009.03.010. Epub 2009 Mar 21.

Abstract

beta-Arrestins are ubiquitously expressed proteins that play important roles in receptor desensitization, endocytosis, proteosomal degradation, apoptosis and signaling. It has been reported that beta-Arrestin2 acts as a scaffold by directly interacting with the JNK3 isoform and recruiting MKK4 and the apoptosis-signaling kinase-1 (ASK1). Here, we report a novel function of beta-Arrestins in regulating H(2)O(2)-induced apoptosis. Our study demonstrates that beta-Arrestins physically associate with C-terminal domain of ASK1, and moreover, both over-expression and RNA interference (RNAi) experiments indicate that beta-Arrestins down-regulate ASK1 protein. In detail, beta-Arrestin-induced reduction of ASK1 protein is due to ubiquitination and proteasome-dependent degradation of ASK1 in response to association of beta-Arrestins and ASK1. Upon H(2)O(2) stimulation, the protein binding between beta-Arrestins and ASK1 increases and ASK1 degradation is expedited. In consequence, beta-Arrestins prevent ASK1-JNK signaling and as a result attenuate H(2)O(2)-induced apoptosis. Structurally, C-terminal domain of ASK1 is essential for beta-Arrestins and ASK1 association. We also found that CHIP is required for beta-Arrestins-induced ASK1 degradation, which suggested that beta-Arrestins function as a scaffold of ASK1 and CHIP, leading to CHIP-mediated ASK1 degradation. All these findings indicate that beta-Arrestins play a negative regulatory role in H(2)O(2)-induced apoptosis signaling through associating with ASK1 and CHIP and facilitating ASK1 degradation, which provides a new insight for analyzing the effects of beta-Arrestins on protecting cells from oxidative stress-induced apoptosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / drug effects*
  • Arrestins / metabolism*
  • Cell Line
  • Down-Regulation / drug effects
  • Enzyme Activation / drug effects
  • Humans
  • Hydrogen Peroxide / pharmacology*
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • MAP Kinase Kinase Kinase 5 / metabolism*
  • Proteasome Endopeptidase Complex / metabolism
  • Protein Binding / drug effects
  • Protein Processing, Post-Translational / drug effects*
  • Ubiquitin / metabolism*
  • Ubiquitin-Protein Ligases / metabolism
  • Ubiquitination / drug effects
  • Up-Regulation / drug effects
  • beta-Arrestins
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • Arrestins
  • Ubiquitin
  • beta-Arrestins
  • Hydrogen Peroxide
  • Ubiquitin-Protein Ligases
  • JNK Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • MAP Kinase Kinase Kinase 5
  • MAP3K5 protein, human
  • Proteasome Endopeptidase Complex