Calcium And Integrin Binding Protein 4 (CIB4)

By database analysis, Gentry et al. (2005) identified CIB4 as a homolog of CIB1. The deduced 185-amino acid CIB4 protein shares structural features with other CIBs, including 10 helices that are separated from one another by loop regions and form 4 EF-hand motifs. All CIBs have a large insertion within EF1, suggesting that this EF-hand cannot bind Ca(2+). In addition, all CIBs have a proline that causes a kink between helices H3a and H3b, which is important for the overall structure of the hydrophobic ligand-binding pocket. Hartz (2006) mapped the CIB4 gene to chromosome 2p23.3 based on an alignment of the CIB4 sequence (GenBank NM_001029881) with the genomic sequence (build 36.1).