Criado Manuel, Castillo Mar, Mulet José, Sala Francisco, Sala Salvador
Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, 03550-Alicante, Spain.
Biochim Biophys Acta. 2010 Mar;1798(3):654-9. doi: 10.1016/j.bbamem.2009.12.013. Epub 2010 Jan 1.
We have studied the role of loop 9 in the function of neuronal nicotinic receptors. By systematically mutating the residues in the loop we have determined that the most important amino acids determining the coupling of binding to gating are the ones closer to the transmembrane region. Single mutations at location E173 in homomeric alpha7 receptors destroyed their function by completely abolishing the current while preserving the expression at the membrane. In contrast, heteromeric receptor alpha3beta4 with the same mutations retained some function. We conclude that loop 9 has a different role in the function of homomeric and heteromeric receptors.
我们研究了第9环在神经元烟碱样受体功能中的作用。通过系统地突变该环中的残基，我们确定决定结合与门控偶联的最重要氨基酸是那些更靠近跨膜区域的氨基酸。同聚α7受体中E173位点的单突变通过完全消除电流而破坏了它们的功能，同时保留了膜上的表达。相比之下，具有相同突变的异聚受体α3β4保留了一些功能。我们得出结论，第9环在同聚和异聚受体的功能中具有不同的作用。
