Identification of a direct interaction between interleukin 2 and the p64 interleukin 2 receptor gamma chain

Proc Natl Acad Sci U S A. 1993 Mar 15;90(6):2428-32. doi: 10.1073/pnas.90.6.2428.

Abstract

The interleukin 2 receptor (IL-2R) consists of at least two subunits, alpha and beta, both of which can bind interleukin 2 (IL-2). Recent studies have demonstrated the existence of a third subunit, a 64-kDa molecule termed IL-2R gamma chain, and have suggested that gamma chain functions to regulate the rate of IL-2 dissociation from the receptor. In the present report we have addressed whether the gamma chain modulates IL-2R affinity by contributing contact sites for IL-2 binding. Using reagents that allow the IL-2R complex to be immunoprecipitated through the IL-2 molecule itself, we demonstrate the existence of a stable IL-2-IL-2R gamma-chain complex. These studies thus establish that the IL-2R gamma chain directly contributes to the IL-2-binding site, consistent with the hypothesis that gamma chain influences IL-2R affinity through its direct interaction with IL-2.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Antibodies, Monoclonal
  • Electrophoresis, Gel, Two-Dimensional
  • Electrophoresis, Polyacrylamide Gel
  • Epitopes / analysis
  • Humans
  • Interleukin-2 / chemistry
  • Interleukin-2 / isolation & purification
  • Interleukin-2 / metabolism*
  • Lymphoma
  • Macromolecular Substances
  • Models, Structural
  • Molecular Sequence Data
  • Receptors, Interleukin-2 / chemistry
  • Receptors, Interleukin-2 / isolation & purification
  • Receptors, Interleukin-2 / metabolism*
  • Recombinant Proteins / metabolism
  • Spectrometry, Fluorescence
  • Thymus Neoplasms
  • Tumor Cells, Cultured

Substances

  • Antibodies, Monoclonal
  • Epitopes
  • Interleukin-2
  • Macromolecular Substances
  • Receptors, Interleukin-2
  • Recombinant Proteins