Premium
Phosphorylation of a tyrosine at the N‐terminus regulates the surface expression of GIRK5 homomultimers
Author(s) -
Mora S. Ivonne,
Escobar Laura I.
Publication year - 2005
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/j.febslet.2005.04.056
Subject(s) - phosphorylation , tyrosine , tyrosine phosphorylation , n terminus , microbiology and biotechnology , expression (computer science) , protein tyrosine phosphatase , chemistry , c terminus , biochemistry , biology , computer science , peptide sequence , gene , amino acid , programming language
The G protein‐coupled inwardly rectifying GIRK5 and Δ5GIRK5 splicing variants do not express functional potassium channels. In contrast, Δ25GIRK5 forms functional homomultimers in Xenopus laevis oocytes. A tyrosine is present at the N‐term of the non‐functional isoforms. We studied the effect of endogenous tyrosine phosphorylation on the GIRK5 surface and functional expression. Unlike wild type channels, GIRK5Y16A and Δ5GIRK5Y16A mutants displayed inwardly rectifying currents and inhibitors of Src tyrosine kinase promoted the traffiking of GIRK5 to the cell surface. This is the first evidence that endogenous phosphorylation of a tyrosine residue in a GIRK channel inhibits its surface expression.