Phosphoproteome dynamics reveal novel ERK1/2 MAP kinase substrates with broad spectrum of functions

Molecular Systems Biology

Mathieu Courcelles¹  Christophe Frémin¹  Laure Voisin¹  Sébastien Lemieux¹  Sylvain Meloche¹ 

[1] Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, Quebec, Canada

关键词: bioinformatics;    cell signaling;    MAP kinases;    phosphoproteomics;    phosphorylation dynamics;   

DOI  :  10.1038/msb.2013.25

来源: Wiley

【 摘 要 】

Abstract

The ERK1/2 MAP kinase pathway is an evolutionarily conserved signaling module that controls many fundamental physiological processes. Deregulated activity of ERK1/2 MAP kinases is associated with developmental syndromes and several human diseases. Despite the importance of this pathway, a comprehensive picture of the natural substrate repertoire and biochemical mechanisms regulated by ERK1/2 is still lacking. In this study, we used large-scale quantitative phosphoproteomics and bioinformatics analyses to identify novel candidate ERK1/2 substrates based on their phosphorylation signature and kinetic profiles in epithelial cells. We identified a total of 7936 phosphorylation sites within 1861 proteins, of which 155 classify as candidate ERK1/2 substrates, including 128 new targets. Candidate ERK1/2 substrates are involved in diverse cellular processes including transcriptional regulation, chromatin remodeling, RNA splicing, cytoskeleton dynamics, cellular junctions and cell signaling. Detailed characterization of one newly identified substrate, the transcriptional regulator JunB, revealed that ERK1/2 phosphorylate JunB on a serine adjacent to the DNA-binding domain, resulting in increased DNA-binding affinity and transcriptional activity. Our study expands the spectrum of cellular functions controlled by ERK1/2 kinases.

Synopsis

Quantitative phosphoproteomics was used to measure the dynamic changes in phosphorylation of ERK1/2 MAP kinases consensus sequences in epithelial cells and to identify 128 novel candidate substrates involved in a broad spectrum of biological functions.

• Global proteomic analysis of dynamic phosphorylation profiles identifies 7936 phosphorylation sites in 1861 proteins.
• A biological filtering strategy identifies 128 novel candidate ERK1/2 MAP kinases substrates.
• Candidate ERK1/2 substrates are involved in a broad spectrum of cellular processes including transcription, RNA splicing, cytoskeleton dynamics and signal transduction.
• ERK1/2 phosphorylation of JunB potentiates DNA binding of c-Fos/JunB heterodimers.

【 授权许可】

CC BY-NC-SA   
Copyright © 2013 EMBO and Macmillan Publishers Limited

Creative Commons Attribution License, which permits distribution, and reproduction in any medium, provided the original author and source are credited. This license does not permit commercial exploitation without specific permission.