SLC38A4 Q969I6

钠耦合中性氨基酸转运蛋白4 (氨基酸转运蛋白A3) (Na(+)耦合中性氨基酸转运蛋白4) (溶质载体家族38成员4) (系统A氨基酸转运蛋白3) (系统N氨基酸转运蛋白3)

功能描述

同向转运蛋白，将中性氨基酸和钠离子从细胞膜外侧共转运至细胞膜内侧 (PubMed:11342143, PubMed:19015196, PubMed:33928121)。该转运是生电性的，依赖于pH，且部分耐受Na(+)被Li(+)替换 (PubMed:11414754)。优先转运较小的氨基酸，如甘氨酸、L-丙氨酸、L-丝氨酸、L-天冬酰胺和L-苏氨酸，其次是L-半胱氨酸、L-组氨酸、L-脯氨酸、L-谷氨酰胺和L-甲硫氨酸 (PubMed:11414754, PubMed:33928121)。 {ECO:0000269|PubMed:11342143, ECO:0000269|PubMed:11414754, ECO:0000269|PubMed:19015196, ECO:0000269|PubMed:33928121}。

组织特异性

Expressed almost exclusively in embryonic and adult liver, and at lower levels in the kidney (PubMed:11342143, PubMed:11414754). Expressed at lower levels in adult muscle and pancreas (PubMed:11414754). Detected in fetal blood vessels (PubMed:16148032). Expressed in syncytiotrophoblas of placenta during first trimester and at term (PubMed:16148032, PubMed:19015196). Highly expressed in first trimester placenta compared to term placenta (PubMed:19015196).

亚细胞定位

Cell membrane