KCNK16 Q96T55

钾通道亚家族K成员16 (2P域钾通道Talk-1) (TWIK相关碱性pH激活K(+)通道1) (TALK-1)

功能描述

K(+)通道，在膜去极化时传导电压依赖性外向整流电流。电压感测以一种“离子流门控”模式与K(+)电化学梯度耦合，其中外向而非内向离子流打开门控 (PubMed:11263999, PubMed:12724142, PubMed:14985088, PubMed:26919430, PubMed:28928238, PubMed:34032641, PubMed:36063992)。同源和异源二聚化形成具有不同调节和门控特性的功能性通道 (PubMed:36063992)。在胰腺胰岛中，传导K(+)逆向电流以促进内质网 (ER) 释放Ca(2+)，并调节与胰腺激素分泌相关的胞质Ca(2+)振荡的频率和持续时间 (PubMed:26239056, PubMed:28928238, PubMed:29402588, PubMed:34032641)。在胰腺β细胞中，驱动ER Ca(2+)外流，进而激活Ca(2+)依赖性质膜K(+)慢电流和胞质Ca(2+)内流，总体上有助于同步的胞质Ca(2+)振荡。限制与第二时相INS分泌相关的葡萄糖诱导的胞质Ca(2+)振荡 (PubMed:26239056, PubMed:28928238, PubMed:34032641)。通过维持正常的胞质Ca(2+)水平和INS分泌，促进β细胞适应急性炎症 (By similarity)。可能通过ER Ca(2+)外流间接调节β细胞线粒体Ca(2+)水平，或通过超极化线粒体膜电位直接调节。在代谢应激下，限制参与葡萄糖稳态的线粒体Ca(2+)振荡和ATP产生 (By similarity)。在胰腺δ细胞中，限制参与生长抑素分泌的Ca(2+)诱导的Ca(2+)释放，并调节参与胰高血糖素分泌的胰岛旁分泌信号传导 (PubMed:29402588)。对其他单价阳离子如Rb(+)和Cs(+)具有通透性 (By similarity) (PubMed:26919430)。 {ECO:0000250|UniProtKB:G5E845, ECO:0000250|UniProtKB:Q96T54, ECO:0000269|PubMed:11263999, ECO:0000269|PubMed:12724142, ECO:0000269|PubMed:14985088, ECO:0000269|PubMed:26239056, ECO:0000269|PubMed:26919430, ECO:0000269|PubMed:28928238, ECO:0000269|PubMed:29402588, ECO:0000269|PubMed:34032641, ECO:0000269|PubMed:36063992}.

组织特异性

Highly expressed in pancreas, in both endocrine (alpha, beta, gamma, delta, and epsilon) and exocrine (acinar and ductal) cells. Expressed in pacreatic beta-cells (at protein level). Expressed in pacreatic delta-cells (at protein level). Not detectable in the other tissues tested.

亚细胞定位

[Isoform a]: Endoplasmic reticulum membrane