AQP4

Also known as aquaporin 4, HMIWC2, MIWC, WCH4, hAQP4

thumb|Secondary (A), Tertiary (B), and Quaternary (C) depictions of an aquaporin channel

Gene data

AQP4

Name: aquaporin 4
Type: protein-coding
Position: 26,852,043–26,865,771 (−)
Aliases: MIWC, MLC4, WCH4, hAQP4
Ensembl: ENSG00000171885
RefSeq RNA: NM_001317384.3, NM_001317387.3, NM_001364286.1, NM_001364287.1, NM_001364289.2
RefSeq protein: NP_001304313.1, NP_001304316.1, NP_001351215.1, NP_001351216.1, NP_001351218.1

This gene encodes a member of the aquaporin family of intrinsic membrane proteins that function as water-selective channels in the plasma membranes of many cells. This protein is the predominant aquaporin found in brain and has an important role in brain water homeostasis. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. Additional isoforms, resulting from the use of alternative in-frame translation initiation codons, have also been described. Recent studies provided evidence for translational readthrough in this gene, and expression of C-terminally extended isoforms via the use of an alternative in-frame translation termination codon. [provided by RefSeq, Jun 2018].

Gene Ontology

Biological process

Article

8 sections

Contents

Structure
Tissue and cellular distribution
Function
Clinical significance
Research
References
Further reading
External links

thumb|Secondary (A), Tertiary (B), and Quaternary (C) depictions of an aquaporin channel

Aquaporin-4, also known as AQP-4, is a water channel protein encoded by the AQP4 gene in humans. AQP-4 belongs to the aquaporin family of integral membrane proteins that conduct water through the cell membrane. A limited number of aquaporins are found within the central nervous system (CNS): AQP1, 3, 4, 5, 8, 9, and 11, but more exclusive representation of AQP1, 4, and 9 are found in the brain and spinal cord. AQP4 shows the largest presence in the cerebellum and spinal cord grey matter. In the CNS, AQP4 is the most prevalent aquaporin channel, specifically located at the perimicrovessel astrocyte foot processes, glia limitans, and ependyma. In addition, this channel is commonly found facilitating water movement near cerebrospinal fluid and vasculature.