Phosphorylation of Rabphilin-3A, a putative target protein for Rab3A, by cyclic AMP-dependent protein kinase

Biochem Biophys Res Commun. 1994 Sep 30;203(3):1927-34. doi: 10.1006/bbrc.1994.2413.

Abstract

Rab3A small GTP-binding protein and its associated proteins, such as Rabphilin-3A, a putative target protein for Rab3A, MSS4, a stimulatory GDP/GTP exchange protein for Rab3A, and Rab GDI, a translocator for the Rab family members including Rab3A, are implicated in neurotransmitter release. We have investigated here the phosphorylation of these proteins by cyclic AMP-dependent protein kinase (protein kinase A). Neither Rab3A, MSS4, nor Rab GDI was phosphorylated, but Rabphilin-3A was phosphorylated Rab GDI was phosphorylated, but Rabphilin-3A was phosphorylated at its N-terminal region. About 0.8 mol of phosphate was maximally incorporated into one mol of Rabphilin-3A. These results suggest that Rabphilin-3A is one of the targets for protein kinase A which modulates neurotransmitter release.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Animals
  • Cell Line
  • Cell Membrane / metabolism
  • Cyclic AMP-Dependent Protein Kinases / metabolism*
  • GTP-Binding Proteins / isolation & purification
  • GTP-Binding Proteins / metabolism*
  • Kinetics
  • Nerve Tissue Proteins / isolation & purification
  • Nerve Tissue Proteins / metabolism*
  • Oligopeptides / metabolism
  • Phosphorylation
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Spodoptera
  • Substrate Specificity
  • Transfection
  • Vesicular Transport Proteins
  • rab GTP-Binding Proteins*
  • rab3 GTP-Binding Proteins

Substances

  • Adaptor Proteins, Signal Transducing
  • Nerve Tissue Proteins
  • Oligopeptides
  • Recombinant Proteins
  • Vesicular Transport Proteins
  • rabphilin-3A
  • kemptide
  • Cyclic AMP-Dependent Protein Kinases
  • GTP-Binding Proteins
  • rab GTP-Binding Proteins
  • rab3 GTP-Binding Proteins