Submitted on May 10, 2004
Accepted on June 1, 2004
Bmx, a member of the Tec family of non-receptor tyrosine kinases, is a novel participant in pharmacological cardioprotection
Jun Zhang1, Peipei Ping1, Guang-wu Wang1, Ming Lu1, Dawn Pantaleon1, Xian-Liang Tang2, Roberto Bolli2, and Thomas M. Vondriska1*
1 Department of Physiology and Medicine/Division of Cardiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
2 Division of Cardiology, University of Louisville, Louisville, KY, USA
* To whom correspondence should be addressed. E-mail: tvondriska{at}mednet.ucla.edu.
Previous studies have indicated that PKC
is a central regulator of protective signal transduction in the heart. However, the signaling modules through which PKC exerts its protective effects have only begun to be understood. We have identified a novel participant in the PKC signaling system in cardioprotection, the non-receptor tyrosine kinase Bmx. Functional proteomic
analyses of PKC signaling complexes identified Bmx as a member of these complexes. Subsequent studies in rabbits have indicated that Bmx is activated by nitric oxide (NO) in the heart concomitant with the late phase of NO donor-induced protection and provide the first analysis of Bmx expression/distribution in the setting of cardioprotection. In addition, increased expression of Bmx induced by NO donors was blocked by the same mechanism that blocked cardioprotection: inhibition of PKC with chelerythrine. These findings indicate that a novel type
of PKC-tyrosine kinase module (involving Bmx) is formed in the heart and may be involved in pharmacological cardioprotection by NO donors.
