Dephosphorylation of CTP-phosphocholine cytidylyltransferase is not required for binding to membranes.

摘要: The sequence of the reversible phosphorylation and activation CTP:phosphocholine cytidylyltransferase was investigated. Treatment primary rat hepatocytes with oleic acid or phospholipase C caused a significant increase in activity amount particulate which correlated decreased protein cytosol. membrane-associated is accompanied by decrease enzyme. Reversal membrane association resulted an increased phosphorylated We wished to determine if dephosphorylation enzyme were prerequisite for its translocation from cytosol membranes. In vitro studies membranes acid- C-treated cells showed that cytosolic associated these negligible dephosphorylation. Incubation different periods time demonstrated active, form subsequently dephosphorylated. This result supported comparison phosphopeptide maps 32P-labeled obtained cytosolic, as well fractions control, acid-treated, cells. These revealed on some sites other sites. Our data strengthen hypothesis change lipid composition can mediate initial binding becomes