CIB1 polyclonal antibody

Platelets regulate the function of Integrin α2b/β3 (GPIIb/IIIa), the platelet Fibrinogen receptor, which is involved in the binding of proteins to integrin cytoplasmic domains. A novel protein, CIB, for calcium- and integrin-binding protein (also designated as Kip for kinase interacting protein, SIP2-28 and DNA-PKcs interacting protein), binds specifically at the cytoplasmic domain of α2b by a number of positively charged residues in its binding site. Binding of CIB to the α2b is affected by fluctuations in the intracellular calcium concentration. In aggregated platelets, endogenous CIB and α2b/β3 translocate to the Triton X-100-insoluble cytoskeleton, demonstrating that the cellular localization of CIB is regulated. CIB also binds to DNA-PKcs, which is a nu-clear protein serine/threonine kinase that plays a role in the DNA repair and recombination process of lymphoid development. Fnk also binds to the CIB, suggesting that CIB may be a regulatory subunit of polo-like kinases. CIB shows significant homology to calcineurin B and calmodulin, and its mRNA levels are ubiquitously expressed in various human tissues.