CCM1 and CCM2 protein interactions in cell signaling: implications for cerebral cavernous malformations pathogenesis.

Published

Journal Article

Cerebral cavernous malformations (CCMs) are sporadically acquired or inherited vascular lesions of the central nervous system consisting of clusters of dilated thin-walled blood vessels that predispose individuals to seizures and stroke. Familial CCM is caused by mutations in KRIT1 (CCM1) or in malcavernin (CCM2), the murine ortholog of which was concurrently characterized as osmosensing scaffold for MEKK3 (OSM). The roles of the CCM proteins in the pathogenesis of the disorder remain largely unknown. Here, we use co-immunoprecipitation, fluorescence resonance energy transfer and subcellular localization strategies to show that the CCM1 gene product, KRIT1, interacts with the CCM2 gene product, malcavernin/OSM. Analogous to the established interactions of CCM1 and beta1 integrin with ICAP1, the CCM1/CCM2 association is dependent upon the phosphotyrosine binding (PTB) domain of CCM2. A familial CCM2 missense mutation abrogates the CCM1/CCM2 interaction, suggesting that loss of this interaction may be critical in CCM pathogenesis. CCM2 and ICAP1 bound to CCM1 via their respective PTB domains differentially influence the subcellular localization of CCM1. Furthermore, we expand upon the established involvement of CCM2 in the p38 mitogen-activated protein kinase signaling module by demonstrating that CCM1 associates with CCM2 and MEKK3 in a ternary complex. These data indicate that the genetic heterogeneity observed in familial CCM may reflect mutation of different molecular members of a coordinated signaling complex.

Full Text

Duke Authors

Cited Authors

  • Zawistowski, JS; Stalheim, L; Uhlik, MT; Abell, AN; Ancrile, BB; Johnson, GL; Marchuk, DA

Published Date

  • September 1, 2005

Published In

Volume / Issue

  • 14 / 17

Start / End Page

  • 2521 - 2531

PubMed ID

  • 16037064

Pubmed Central ID

  • 16037064

International Standard Serial Number (ISSN)

  • 0964-6906

Digital Object Identifier (DOI)

  • 10.1093/hmg/ddi256

Language

  • eng

Conference Location

  • England