Palacín M, Estévez R, Zorzano A
Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Spain.
Curr Opin Cell Biol. 1998 Aug;10(4):455-61. doi: 10.1016/s0955-0674(98)80058-6.
The proteins rBAT (related to bo,+ amino acid transporter) and 4F2hc (the heavy chain of the surface antigen 4F2) are homologous proteins that induce amino acid transport in Xenopus oocytes. The role of rBAT in amino acid transport is substantiated by the fact that mutations in the gene encoding it cause cystinuria, a heritable disease characterised by high concentrations of cystine in the urine. Structural and functional evidence supports the hypothesis that both rBAT and 4F2hc proteins form part of heterodimeric amino acid transporters. There is new evidence that the functional unit of system y+L amino acid transporter is a disulfide bridge-dependent complex of 4F2hc with a Xenopus oocyte plasma membrane protein.
蛋白质rBAT（与b⁰，+氨基酸转运体相关）和4F2hc（表面抗原4F2的重链）是同源蛋白，可诱导非洲爪蟾卵母细胞中的氨基酸转运。编码rBAT的基因突变会导致胱氨酸尿症，这是一种遗传性疾病，其特征是尿液中胱氨酸浓度很高，这一事实证实了rBAT在氨基酸转运中的作用。结构和功能证据支持这样的假说，即rBAT和4F2hc蛋白都是异二聚体氨基酸转运体的组成部分。有新证据表明，y⁺L系统氨基酸转运体的功能单元是4F2hc与非洲爪蟾卵母细胞质膜蛋白形成的二硫键依赖性复合物。
