Figure 3.
Muscarinic receptor signaling regulates the ability of PYK2 to phosphorylate the carboxy terminus of Kv1.2. (A) Autoradiograph of immune complex PYK2 kinase assays of PYK2 immunoprecipitated from cells expressing PYK2-HSV. Lysates prepared before (−) and after (+) carbachol stimulation (2 min, 50 μM) were mixed with purified GST, the cytosolic Kv1.2 amino terminus purified as a GST-fusion protein (GST-Kv1.2/N), or the cytosolic Kv1.2 carboxy terminus purified as a GST-fusion protein (GST-Kv1.2/C) in the presence of [γ-32P]ATP and kinase buffer. Control assays with the GST-Kv1.2/C substrate omitted the primary anti-HSV antibody. (B) The same gel visualized by Coomassie blue staining.