Dissociation of the eukaryotic initiation factor-4E/4E-BP1 complex involves phosphorylation of 4E-BP1 by an mTOR-associated kinase

FEBS Lett. 1999 Sep 3;457(3):489-93. doi: 10.1016/s0014-5793(99)01094-7.

Abstract

mTOR immunoprecipitates contain two 4E-BP1 protein kinase activities. One appears to be due to mTOR itself and results in the phosphorylation of 4E-BP1 on residues T(36) and T(45), as shown previously by others. The other is a kinase which can be separated from mTOR and which phosphorylates 4E-BP1 within a peptide(s) containing residues S(64) and T(69). This phosphorylation, which occurs predominantly on S(64), results in the dissociation of 4E-BP1 from eIF-4E.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Carrier Proteins*
  • Eukaryotic Initiation Factor-4E
  • Intracellular Signaling Peptides and Proteins
  • Male
  • Molecular Sequence Data
  • Peptide Initiation Factors / genetics
  • Peptide Initiation Factors / immunology
  • Peptide Initiation Factors / metabolism*
  • Phosphoproteins / genetics
  • Phosphoproteins / immunology
  • Phosphoproteins / metabolism*
  • Phosphorylation
  • Phosphotransferases (Alcohol Group Acceptor) / isolation & purification
  • Phosphotransferases (Alcohol Group Acceptor) / metabolism*
  • Precipitin Tests
  • Protein Kinases / immunology
  • Protein Kinases / isolation & purification
  • Protein Kinases / metabolism*
  • Rats
  • Rats, Wistar
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • TOR Serine-Threonine Kinases

Substances

  • Carrier Proteins
  • Eif4ebp1 protein, rat
  • Eukaryotic Initiation Factor-4E
  • Intracellular Signaling Peptides and Proteins
  • Peptide Initiation Factors
  • Phosphoproteins
  • Recombinant Proteins
  • Protein Kinases
  • Phosphotransferases (Alcohol Group Acceptor)
  • TOR Serine-Threonine Kinases
  • mTOR protein, rat