Multiple site phosphorylation of tyrosine hydroxylase. Differential regulation in situ by a 8-bromo-cAMP and acetylcholine.

Suspension cultures of purified bovine adrenal chromaffin cells incorporated 32P from exogenous 32Pi into a protein of approximately M4 = 60,000 (isolated by discontinuous, sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis). Phosphorylated tyrosine hydroxylase, purified from chromaffin cell supernatants by immunoprecipitation, co-migrated with the Mr = 60,000 band. Tryptic fragments p…