Cytoplasmic binding partners of the platelet integrin alphaIIb beta3

Melissa A Bonner1, Ulhas P Naik

  • 1Delaware Biotechnology Institute, Newark, DE, USA.

Platelets function physiologically in mediating hemostasis, but are also associated with many pathological conditions, such as thrombosis, which can lead to myocardial infarction and/or stroke. Therefore, the study of platelet regulation and signaling has been of great interest and is necessary for generating effective anti-platelet therapeutics. One platelet signaling molecule of particular interest is the integrin alphaIIb beta3, which binds Fg and mediates platelet cross-linking. The integrin itself as well as cytoplasmic proteins that interact with alphaIIb beta3 have become potential targets for anti-platelet therapies. One such protein that has been shown to directly regulate alphaIIb beta3 function is calcium- and integrin-binding protein 1 (CIB1). CIB1 has been implicated in alphaIIb beta3 activation and outside-in signaling through the integrin. By increasing our understanding of CIB1 and other proteins that like it, associate with integrin alphaIIb beta3, and the signaling events that result from those interactions, we may bring ourselves closer to more effective therapies. In the present work, we explore known cytoplasmic binding partners of the integrin alphaIIb beta3 and their effect on alphaIIb beta3, focusing on CIB1.

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