| Primary Identifier | IPR037768 | Type | Domain |
| Short Name | C2B_Copine |
| description | 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 [, ]. In plants, they are known as BONZAI proteins []. The copine family in plants may have effects in promoting growth and development in addition to repressing cell death [, ]. Caenorhabditis elegans copine, also known as Nra1, is Involved in nicotinic acetylcholine receptor (nAChR)-mediated sensitivity to nicotine and levamisole []. C2 domains fold into an 8-standed β-sandwich that can adopt 2 structural arrangements: type I and type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This entry represents the second C2 repeat of copines, C2B, and has a type-I topology. The C2B domains of copine-2, copine-6 and copine-7 have been shown to be responsible for the protein calcium-dependent membrane association []. |
