SELECTIVE PHOSPHORYLATION OF THE ALPHA-SUBUNIT OF THE SODIUM-CHANNEL BY CAMP-DEPENDENT PROTEIN-KINASE
- 1 January 1982
- journal article
- research article
- Vol. 257 (14), 7918-7921
Abstract
The .alpha. subunit of the sodium channel purified from rat brain is rapidly and selectively phosphorylated by the catalytic subunit of cAMP-dependent protein kinase to a level of 3 to 4 mol of 32P/mol of saxitoxin-binding activity. The rate of phosphorylation is comparable to that of the synthetic peptide analog of the phosphorylation site of pyruvate kinase, one of the best substrates for cAMP-dependent protein kinase. An endogenous cAMP-dependent protein kinase that is present in the partially purified sodium channel preparations also selectively phosphorylates the .alpha. subunit. The specificity and rapidity of the phosphorylation reaction are consistent with the hypothesis that the .alpha. subunit is phosphorylated by cAMP-dependent protein kinase in vivo.This publication has 3 references indexed in Scilit:
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