Association of human immunodeficiency virus Nef protein with actin is myristoylation dependent and influences its subcellular localization

Eur J Biochem. 1997 Aug 1;247(3):843-51. doi: 10.1111/j.1432-1033.1997.00843.x.

Abstract

Human immunodeficiency virus (HIV) Nef functions are thought to be mediated via interactions with cellular proteins. Utilizing zone velocity sedimentation in glycerol gradients we found that recombinant HIV-1 Nef non-covalently associates with actin forming a high-molecular-mass complex of 150-300 kDa. This Nef/actin complex was present in human B and T lymphocytes but not in insect cells and was dependent on the N-terminal myristoylation of Nef, whereas the SH3-binding proline motif of Nef was not involved. Despite being myristoylated, HIV-2 Nef did not associate with actin. This might reflect differences in the subcellular localization of Nef since cell-fractionation experiments revealed that HIV-1 Nef was virtually exclusively localized in the cytoskeletal (detergent-insoluble) fraction whereas HIV-2 Nef had significantly reduced affinity for the cytoskeleton. Colocalization experiments in HIV-1-infected CD4+ fibroblasts revealed that Nef/actin complexes may also exist in HIV-infected cells. This novel interaction of HIV-1 Nef with actin provides insight into the association of Nef with cellular structures and reveals general differences in the interactions of the Nef proteins from HIV-1 and HIV-2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism*
  • Animals
  • Cell Line
  • Gene Products, nef / chemistry
  • Gene Products, nef / metabolism*
  • HIV-1 / metabolism*
  • HIV-2 / metabolism*
  • Molecular Weight
  • Myristic Acid
  • Myristic Acids / metabolism
  • Protein Binding
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Spodoptera
  • Subcellular Fractions / metabolism*
  • T-Lymphocytes / metabolism
  • nef Gene Products, Human Immunodeficiency Virus

Substances

  • Actins
  • Gene Products, nef
  • Myristic Acids
  • Recombinant Proteins
  • nef Gene Products, Human Immunodeficiency Virus
  • Myristic Acid