SLC22A11
Description
The SLC22A11 (solute carrier family 22 member 11) is a protein-coding gene located on chromosome 11.
Solute carrier family 22 member 11 (SLC22A11) is a protein encoded by the SLC22A11 gene in humans. It plays a crucial role in the sodium-independent transport and excretion of organic anions, some of which can be potentially toxic. SLC22A11 is an integral membrane protein primarily found in the kidney and placenta. In the placenta, it helps prevent harmful organic anions from reaching the fetus.
SLC22A11, also known as Organic anion transporter 4 (OAT4) and Organic anion:dicarboxylate exchanger OAT4, is an antiporter protein that facilitates the transport of conjugated steroids and other specific organic anions across cell membranes. It operates at the basal membrane of syncytiotrophoblast and the apical membrane of proximal tubule epithelial cells, exchanging these organic anions for anionic compounds. This exchange process is critical for various physiological functions. In the placenta, OAT4 is responsible for the absorption of fetal-derived steroid sulfates like estrone sulfate (E1S) and dehydroepiandrosterone sulfate (DHEA-S). Additionally, it plays a role in eliminating waste products and xenobiotics from the fetus, contributing to placental urate homeostasis. In the kidneys, OAT4 facilitates the reabsorption of organic anions such as urate and steroid sulfates. It utilizes glutarate as a counter-anion for E1S uptake in the kidneys. The transport mechanism involves exchange reactions, including DHEA-S/E1S, E1S/Cl(-), E1S/OH(-), urate/Cl(-), and urate/OH(-). OAT4 also participates in the transport of prostaglandins E2 and F2-alpha, potentially influencing their renal excretion. Furthermore, it can uptake anionic drugs, diuretics, bile salts, and ochratoxin A. Interestingly, OAT4 mediates the unidirectional efflux of glutamate and aspartate. Glutamate efflux down its transmembrane gradient may drive SLC22A11/OAT4-mediated placental uptake of E1S.
SLC22A11 is also known as OAT4, hOAT4.
