InterPro domain: IPR045052

Copines are a widely distributed class of Ca2+-dependent lipid-binding proteins. Most have a characteristic domain structure: two C2 domains in the N-terminal region and a von Willebrand A (VWA) domain in the C-terminal region. They are potentially involved in membrane trafficking, protein-protein interactions, and perhaps even cell division and growth [ 1 , 2 ]. In plants, they are known as BONZAI proteins [ 3 ]. The copine family in plants may have effects in promoting growth and development in addition to repressing cell death [ 4 , 5 ]. Caenorhabditis elegans copine, also known as Nra1, is Involved in nicotinic acetylcholine receptor (nAChR)-mediated sensitivity to nicotine and levamisole [ 6 ].

1. 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
2. Copines: a ubiquitous family of Ca(2+)-dependent phospholipid-binding proteins. Cell. Mol. Life Sci. 59, 1467-77
3. Identification and analysis of copine/BONZAI proteins among evolutionarily diverse plant species. Genome 59, 565-73
4. Plant growth homeostasis is controlled by the Arabidopsis BON1 and BAP1 genes. Genes Dev. 15, 2263-72
5. The BON/CPN gene family represses cell death and promotes cell growth in Arabidopsis. Plant J. 45, 166-79
6. Identification and characterization of novel nicotinic receptor-associated proteins in Caenorhabditis elegans. EMBO J. 24, 2566-78