The name of this superfamily has been modified since the most recent official CATH+ release (v4_3_0). At the point of the last release, this superfamily was named:

Calcium release-activated calcium channel protein Orai

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.

Superfamily: Calcium release-activated calcium channel protein Orai

This superfamily includes Drosophila Orai and human Orai1, Orai2 and Orai3. Orai is a plasma membrane protein which forms the pore of the CRAC channel (calcium release-activated calcium channel) and generates sustained cytosolic calcium signals when triggered by depletion of calcium from the endoplasmic reticulum. Six Orai subunits assemble around a central ion pore to form a hexameric channel. The pore traverses the membrane and extends 20 angstroms into the cytosol. A ring of glutamates on its extracellular side forms the selectivity filter and a basic region near the intracellular side is able to bind anions that may stabilize the closed state. The architecture of this channel greatly differs from other ion channels, giving insight into the way selective calcium permeation and gating is achieved PMID:23180775.

GO Diversity

Unique GO annotations
26 Unique GO terms

EC Diversity

Unique EC annotations
0 Unique EC terms

Species Diversity

Unique species annotations
457 Unique species

Sequence/Structure Diversity

Overview of the sequence / structure diversity of this superfamily compared to other superfamilies in CATH. Click on the chart to view the data in more detail.

Superfamily Summary

A general summary of information for this superfamily.
Domains: 4
Domain clusters (>95% seq id): 1
Domain clusters (>35% seq id): 1
Unique PDBs: 2
Structural Clusters (5A): 1
Structural Clusters (9A): 1
FunFam Clusters: 11
Unique EC:
Unique GO: 26
Unique Species: 457