SLC22A4 Q9H015

溶质载体家族22成员4 (麦角硫因转运蛋白) (ET转运蛋白) (ETTh) (有机阳离子/肉碱转运蛋白1) (OCTN1)

功能描述

介导内源性和微生物两性离子及有机阳离子转运的转运蛋白 (PubMed:10215651, PubMed:15107849, PubMed:15795384, PubMed:16729965, PubMed:20601551, PubMed:22206629, PubMed:22569296, PubMed:29530864)。作为Na(+)依赖性和pH依赖性的高亲和力微生物同向转运蛋白，转运强效食物来源的抗氧化剂麦角硫因 (PubMed:15795384, PubMed:29530864, PubMed:33124720)。伴随一个麦角硫因分子转运一个钠离子 (By similarity)。参与小肠和肾小管细胞腔面/顶端侧以及非实质肝细胞对麦角硫因的吸收，从而有助于维持体内麦角硫因的稳态水平 (PubMed:20601551)。也介导乙酰胆碱的双向转运，尽管确切的转运机制尚未完全阐明 (PubMed:22206629)。极可能在非神经组织中输出抗炎乙酰胆碱，从而有助于非神经胆碱能系统 (PubMed:22206629, PubMed:22569296)。通过控制炎症和氧化应激显示出与更好存活率相关的一般生理作用，这可能与麦角硫因和乙酰胆碱的转运有关 (PubMed:15795384, PubMed:22206629)。也可能作为低亲和力Na(+)依赖性L-肉碱转运蛋白通过线粒体膜发挥作用，从而维持细胞内肉碱稳态 (PubMed:10215651, PubMed:15107849, PubMed:16729965)。可能有助于调节睾丸中跨血睾屏障的阳离子化合物转运 (PubMed:35307651)。 {ECO:0000250|UniProtKB:Q9R141, ECO:0000269|PubMed:10215651, ECO:0000269|PubMed:15107849, ECO:0000269|PubMed:15795384, ECO:0000269|PubMed:16729965, ECO:0000269|PubMed:20601551, ECO:0000269|PubMed:22206629, ECO:0000269|PubMed:22569296, ECO:0000269|PubMed:29530864, ECO:0000269|PubMed:35307651}。

组织特异性

Widely expressed (PubMed:9426230). Highly expressed in kidney, trachea, ileum, bone marrow and whole blood (PubMed:15795384, PubMed:9426230). Expressed in small intestines (PubMed:20601551). Weakly expressed in skeletal muscle, prostate, lung, pancreas, placenta, heart, uterus, spleen and spinal cord (PubMed:15795384, PubMed:16729965, PubMed:9426230). Expressed in testis, primarily to the basal membrane of Sertoli cells (PubMed:16729965, PubMed:35307651). Expressed in brain (PubMed:16729965). Expressed in liver (PubMed:16729965). Highly expressed in intestinal cell types affected by Crohn disease, including epithelial cells. Expressed in CD68 macrophage and CD43 T-cells but not in CD20 B-cells (PubMed:15107849). Predominantly expressed in CD14 cells in peripheral blood mononuclear cells (PubMed:14608356). Expressed in fetal liver, kidney and lung (PubMed:15795384, PubMed:9426230).

亚细胞定位

Apical cell membrane