The Tyrosine Kinase c-Src Specifically Binds to the Active Integrin αIIbβ3 to Initiate Outside-in Signaling in Platelets.

ABSTRACT: It is currently believed that inactive tyrosine kinase c-Src in platelets binds to the cytoplasmic tail of the β3 integrin subunit via its SH3 domain. Although a recent NMR study supports this contention, it is likely that such binding would be precluded in inactive c-Src because an auto-inhibitory linker physically occludes the β3 tail binding site. Accordingly, we have re-examined c-Src binding to β3 by immunoprecipitation as well as NMR spectroscopy. In unstimulated platelets, we detected little to no interaction between c-Src and β3. Following platelet activation, however, c-Src was co-immunoprecipitated with β3 in a time-dependent manner and underwent progressive activation as well. We then measured chemical shift perturbations in the (15)N-labeled SH3 domain induced by the C-terminal

SUBMITTER: Wu Y 

PROVIDER: S-EPMC4505490 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature