| Primary Identifier | IPR004010 | Type | Domain |
| Short Name | Double_Cache_2 |
| description | Cache is an extracellular domain that is predicted to have a role in small-molecule recognition in a wide range of proteins, including the animal dihydropyridine-sensitive voltage-gated Ca2 channel alpha-2delta subunit, and various bacterial chemotaxis receptors. The name Cache comes from CAlcium channels and CHEmotaxis receptors. The Cache domain, also known as the extracellular PAS domain, consists of an N-terminal part with three predicted strands and an α-helix, and a C-terminal part with a strand dyad followed by a relatively unstructured region. The N-terminal portion of the Cache domain containing the three predicted strands could form a sheet analogous to that present in the core of the PAS domain structure. Cache domains are particularly widespread in bacteria, such as Vibrio cholerae. The animal calcium channel alpha-2delta subunits might have acquired a part of their extracellular domains from a bacterial source []. The Cache domain appears to have arisen from the GAF-PAS fold, despite their divergent functions [, ].This entry represents the double Cache domain 2 (dCache_2), which may be a result of single Cache domain 2 (sCache_2) duplication []. |