InterPro domain: IPR010734

This represents a conserved region approximately 180 residues long within eukaryotic copines. Copines are Ca ²⁺ -dependent phospholipid-binding proteins that are thought to be involved in membrane-trafficking, and may also be involved in cell division and growth [ 1 ]. They were originally identified in paramecium. They are found in human and orthologues have been found in C. elegans and Arabidopsis Thaliana. None have been found in D. Melanogaster or S. Cereviciae. Phylogenetic distribution suggests that copines have been lost in some eukaryotes [ 2 ]. No functional properties have been assigned to the VWA domains present in copines. The members of this subgroup contain a functional MIDAS motif based on their preferential binding to magnesium and manganese. However, the MIDAS motif is not totally conserved, in most cases the MIDAS consists of the sequence DxTxS instead of the motif DxSxS that is found in most cases. The C2 domains present in copines mediate phospholipid binding [ 3 , 4 ].

1. Copines: a ubiquitous family of Ca(2+)-dependent phospholipid-binding proteins. Cell. Mol. Life Sci. 59, 1467-77
2. The copines, a novel class of C2 domain-containing, calcium-dependent, phospholipid-binding proteins conserved from Paramecium to humans. J. Biol. Chem. 273, 1393-402
3. Distribution and evolution of von Willebrand/integrin A domains: widely dispersed domains with roles in cell adhesion and elsewhere. Mol. Biol. Cell 13, 3369-87
4. Evolution of von Willebrand factor A (VWA) domains. Biochem. Soc. Trans. 27, 835-40