Language selection

Government of Canada / Gouvernement du Canada

Search

Localization of endogenous Grb10 to the mitochondria and its interaction with the mitochondrial-associated Raf-1 pool

From National Research Council Canada

DOIResolve DOI: https://doi.org/10.1074/jbc.274.50.35719
AuthorSearch for: 1; Search for: 1; Search for:
Affiliation
  1. National Research Council of Canada. NRC Biotechnology Research Institute
FormatText, Article
ISSN0021-9258
0021-9258
1083-351X
0021-9258
1083-351X
Subjectcell line; cell membrane; cloning, molecular; COS cells; fluorescent antibody technique; GRB10 adaptor protein; HeLa cells; HL-60 cells; insulin-like growth factor I; MAP kinase kinase 1; mitochondria; mitogen-activated protein kinase kinases; protein-serine-threonine kinases; proteins; proto-oncogene proteins c-raf; receptor, epidermal growth factor; recombinant proteins; tumor cells, cultured; ultraviolet rays
Abstract
Grb10 belongs to a small family of adapter proteins that are known to interact with a number of receptor tyrosine kinases and signaling molecules. We have recently demonstrated that the Grb10 SH2 domain interacts with both the Raf-1 and MEK1 kinases. Overexpression of Grb10 genes with mutations in their SH2 domains promotes apoptosis in cultured cells, a phenotype that is reversed by concomitant overexpression of the wild type gene. Using immunofluorescence microscopy and subcellular fractionation we now show that most of the Grb10 molecules are peripherally associated with mitochondria. Following insulin-like growth factor I or serum treatment, small pools of Grb10 can also be found at the plasma membrane and in actin-rich membrane ruffles, whereas overexpression of Grb10 leads to its mislocalization to the cytosol. Two-hybrid analysis shows that the Grb10-binding site on Raf-1 co-localizes with its Ras-binding domain. Finally, we show that the endogenous Grb10 and Raf-1 proteins can be co-immunoprecipitated from a partially purified mitochondrial extract, an interaction that is enhanced following the activation of Raf-1 by ultraviolet radiation. Thus, we infer that Grb10 may regulate signaling between plasma membrane receptors and the apoptosis-inducing machinery on the mitochondrial outer membrane by modulating the anti-apoptotic activity of mitochondrial Raf-1.
Publication date
PublisherAmerican Society for Biochemistry and Molecular Biology
In
  • The Journal of Biological Chemistry 274, no. 50: 35719–35724.
NoteUI - 20054454
LanguageEnglish
Peer reviewedYes
Identifier10008196
NRC numberNRC-BRI-41480
NPARC number12328572
Export citationExport as RIS
Report a correctionReport a correction (opens in a new tab)
Record identifierd315c1d0-7b1b-453f-be04-923e70dd501a
Record created2009-09-10
Record modified2020-03-20
Date modified: