Chloride channel accessory 3, also known as CLCA3, is a protein which in humans is encoded by the CLCA3Ppseudogene. The protein encoded by this gene is a chloride channel.[3] According to the HGNC, this protein is not expressed in humans but is in certain other species such as mouse. However, some conflicting reports state that human cells produce and glycosylate this protein.[3]
This gene is a transcribed pseudogene belonging to the calcium sensitive chloride conductance protein family. To date, all members of this gene family map to the same site on chromosome 1p31-p22 and share high degrees of homology in size, sequence and predicted structure, but differ significantly in their tissue distributions. This gene contains several nonsense codons compared to other family members that render the transcript a candidate for nonsense-mediated mRNA decay (NMD), although this gene is translated into a well characterized protein which has been shown to decorate mucin granule containing vesicles. Protein structure prediction methods suggest the N-terminal region of CLCA3 protein is a zinc metalloprotease, and the protein is not an ion channel per se.[4]
^Pawłowski K, Lepistö M, Meinander N, Sivars U, Varga M, Wieslander E (May 2006). "Novel conserved hydrolase domain in the CLCA family of alleged calcium-activated chloride channels". Proteins. 63 (3): 424–39. doi:10.1002/prot.20887. PMID16470849. S2CID40041491.
Pauli BU, Abdel-Ghany M, Cheng HC, Gruber AD, Archibald HA, Elble RC (November 2000). "Molecular characteristics and functional diversity of CLCA family members". Clinical and Experimental Pharmacology & Physiology. 27 (11): 901–5. doi:10.1046/j.1440-1681.2000.03358.x. PMID11071307. S2CID28762005.
Gruber AD, Pauli BU (October 1999). "Clustering of the human CLCA gene family on the short arm of chromosome 1 (1p22-31)". Genome. 42 (5): 1030–2. doi:10.1139/gen-42-5-1030. PMID10584316.