Role of loop 9 on the function of neuronal nicotinic receptors

AbstractWe 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 α7 receptors destroyed their function by completely abolishing the current while preserving the expression at the membrane. In contrast, heteromeric receptor α3β4 with the same mutations retained some function. We conclude that loop 9 has a different role in the function of homomeric and heteromeric receptors

Role of loop 9 on the function of neuronal nicotinic receptors

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 alpha 7 receptors destroyed their function by completely abolishing the current while preserving the expression at the membrane. In contrast, heteromeric receptor alpha 3 beta 4 with the same mutations retained some function. We conclude that loop 9 has a different role in the function of homomeric and heteromeric receptors. (C) 2009 Elsevier B.V. All rights reserved.This work was supported by grants from the Ministerio de Educación y Ciencia of Spain and FEDER (SAF2005-00534, SAF2005- 02045 and SAF2006-03933) and grants BFU2008-02160 and CSD2008-00005 (The Spanish Ion Channel Initiative-CONSOLIDER INGENIO 2010) from the Ministerio de Ciencia e Innovación of Spain.Peer Reviewe