KCNS3 Antibody - #DF9769

Potassium channel subunit that does not form functional channels by itself. Can form functional heterotetrameric channels with KCNB1; modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1. Heterotetrameric channel activity formed with KCNB1 show increased current amplitude with the threshold for action potential activation shifted towards more negative values in hypoxic-treated pulmonary artery smooth muscle cells (By similarity).

Cell membrane>Multi-pass membrane protein.
Note: May not reach the plasma membrane but remain in an intracellular compartment in the absence of KCNB1 (PubMed:10484328).

Detected in whole normal term placental and placental chorionic plate arteries and veins. Detected in syncytiotrophoblast and in blood vessel endothelium within intermediate villi and chorionic plate (at protein level). Detected in most tissues, but not in peripheral blood lymphocytes. The highest levels of expression are in lung.

Heterotetramer with KCNB1. Does not form homomultimers.

The transmembrane segment S4 functions as voltage-sensor and is characterized by a series of positively charged amino acids at every third position. Channel opening and closing is effected by a conformation change that affects the position and orientation of the voltage-sensor paddle formed by S3 and S4 within the membrane. A transmembrane electric field that is positive inside would push the positively charged S4 segment outwards, thereby opening the pore, while a field that is negative inside would pull the S4 segment inwards and close the pore. Changes in the position and orientation of S4 are then transmitted to the activation gate formed by the inner helix bundle via the S4-S5 linker region.

Belongs to the potassium channel family. S (TC 1.A.1.2) subfamily. Kv9.3/KCNS3 sub-subfamily.