水稻氨基酸通透酶（AAPs）的转运功能

Transport Function of Rice Amino Acid Permeases (AAPs).

作者信息

Taylor Margaret R, Reinders Anke, Ward John M

机构信息

Department of Plant Biology, University of Minnesota, St. Paul, MN 55108, USA.

Department of Plant Biology, University of Minnesota, St. Paul, MN 55108, USA

出版信息

Plant Cell Physiol. 2015 Jul;56(7):1355-63. doi: 10.1093/pcp/pcv053. Epub 2015 Apr 22.

DOI:10.1093/pcp/pcv053

PMID:25907566

Abstract

The transport function of four rice (Oryza sativa) amino acid permeases (AAPs), OsAAP1 (Os07g04180), OsAAP3 (Os06g36180), OsAAP7 (Os05g34980) and OsAAP16 (Os12g08090), was analyzed by expression in Xenopus laevis oocytes and electrophysiology. OsAAP1, OsAAP7 and OsAAP16 functioned, similarly to Arabidopsis AAPs, as general amino acid permeases. OsAAP3 had a distinct substrate specificity compared with other rice or Arabidopsis AAPs. OsAAP3 transported the basic amino acids lysine and arginine well but selected against aromatic amino acids. The transport of basic amino acids was further analyzed for OsAAP1 and OsAAP3, and the results support the transport of both neutral and positively charged forms of basic amino acids by the rice AAPs. Cellular localization using the tandem enhanced green fluorescent protein (EGFP)-red fluorescent protein (RFP) reporter pHusion showed that OsAAP1 and OsAAP3 localized to the plasma membrane after transient expression in onion epidermal cells or stable expression in Arabidopsis.

摘要

通过在非洲爪蟾卵母细胞中表达并利用电生理学方法，分析了四种水稻（Oryza sativa）氨基酸通透酶（AAPs），即OsAAP1（Os07g04180）、OsAAP3（Os06g36180）、OsAAP7（Os05g34980）和OsAAP16（Os12g08090）的转运功能。与拟南芥AAPs类似，OsAAP1、OsAAP7和OsAAP16作为通用氨基酸通透酶发挥作用。与其他水稻或拟南芥AAPs相比，OsAAP3具有独特的底物特异性。OsAAP3能很好地转运碱性氨基酸赖氨酸和精氨酸，但对芳香族氨基酸有选择性排斥。对OsAAP1和OsAAP3的碱性氨基酸转运进行了进一步分析，结果支持水稻AAPs对碱性氨基酸的中性和带正电荷形式均有转运。使用串联增强型绿色荧光蛋白（EGFP）-红色荧光蛋白（RFP）报告基因pHusion进行细胞定位显示，OsAAP1和OsAAP3在洋葱表皮细胞中瞬时表达或在拟南芥中稳定表达后定位于质膜。