The 93 kDa protein gephyrin and tubulin associated with the inhibitory glycine receptor are phosphorylated by an endogenous protein kinase

FEBS Letters

Langosch, Dieter¹  Betz, Heinrich¹  Hoch, Werner¹ 

[1] Max-Planck-Institut für Hirnforschung, Abteilung Neurochemie, 6000 Frankfurt, Germany

关键词: Glycine receptor;    Tubulin;    Protein phosphorylation;    GlyR;    glycine receptor;    SDS-PAGE;    sodium dodecyl sulfate polyacrylamide gel electrophoresis;   

DOI  :  10.1016/0014-5793(92)80034-E

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The 93 kDa protein gephyrin is a tubulin binding peripheral membrane protein that is associated with the inhibitory glycine receptor and has been implicated in its anchoring at central synapses. Here, we demonstrate that gephyrin as well as co-purifying tubulin are phosphorylated by a kinase activity which is endogenous to highly purified glycine receptor preparations. This kinase phosphorylates serine and threonine residues and utilizes ATP, but not GTP, as phosphate donor. Its activity is not affected by various activators and/or inhibitors of cyclic nucleotide-dependent kinases, calcium/calmodulin-dependent kinases, or protein kinase C. A five-fold stimulation of kinase activity was, however, observed in the presence of poly-lysine. Phosphorylation of gephyrin and/or tubulin might regulate receptor/cytoskeleton interactions at postsynaptic membrane specializations.

【 授权许可】

Unknown