Immunophilins control T lymphocyte adhesion and migration by regulating CrkII binding to C3G Academic Article uri icon


  • Crk adaptor proteins are key players in signal transduction from a variety of cell surface receptors. CrkI and CrkII, the two alternative spliced forms of CRK, possess an N-terminal Src homology 2 domain, followed by a Src homology 3 (SH3) domain, whereas CrkII possesses in addition a C-terminal linker region plus a SH3 domain, which operate as regulatory moieties. In this study, we investigated the ability of immunophilins, which function as peptidyl-prolyl isomerases, to regulate Crk proteins in human T lymphocytes. We found that endogenous CrkII, but not CrkI, associates with the immunophilins, cyclophilin A, and 12- kDa FK506-binding protein, in resting human Jurkat T cells. In addition, cyclophilin A increased Crk SH3 domain–binding guanine-nucleotide releasing factor (C3G) binding to CrkII, whereas inhibitors of immunophilins, such as cyclosporine A (CsA) and FK506 …

publication date

  • October 15, 2014