Manel Nicolas, Battini Jean-Luc, Sitbon Marc
Institut de Génétique Moléculaire de Montpellier, CNRS UMR 5535, IFR 122, 1919 route de Mende, F-34293 Montpellier Cedex 5, France.
J Biol Chem. 2005 Aug 12;280(32):29025-9. doi: 10.1074/jbc.M504549200. Epub 2005 Jun 13.
The glucose transporter GLUT1, a member of the multimembrane-spanning facilitative nutrient transporter family, serves as a receptor for human T cell leukemia virus (HTLV) infection. Here, we show that the 7 amino acids of the extracellular loop 6 of GLUT1 (ECL6) placed in the context of the related GLUT3 transporter were sufficient for HTLV envelope binding. Glutamate residue 426 in ECL6 was identified as critical for binding. However, binding to ECL6 was not sufficient for HTLV envelope-driven infection. Infection required two additional determinants located in ECL1 and ECL5, which otherwise did not influence HTLV envelope binding. Moreover the single N-glycosylation chain located in ECL1 was not required for HTLV infection. Therefore, binding involves a discrete determinant in the carboxyl terminal ECL6, whereas post-binding events engage extracellular sequences in the amino and carboxyl terminus of GLUT1.
葡萄糖转运蛋白GLUT1是跨膜促进性营养物质转运蛋白家族的成员，它作为人类T细胞白血病病毒（HTLV）感染的受体。在此，我们表明，置于相关GLUT3转运蛋白背景下的GLUT1细胞外环6（ECL6）的7个氨基酸足以实现HTLV包膜结合。ECL6中的谷氨酸残基426被确定为结合的关键因素。然而，与ECL6的结合不足以实现HTLV包膜驱动的感染。感染需要位于ECL1和ECL5中的另外两个决定因素，否则它们不会影响HTLV包膜结合。此外，位于ECL1中的单个N-糖基化链对于HTLV感染不是必需的。因此，结合涉及羧基末端ECL6中的一个离散决定因素，而后结合事件涉及GLUT1氨基和羧基末端的细胞外序列。
