Binding of human prothymosin alpha to the leucine-motif/activation domains of HTLV-I Rex and HIV-1 Rev

Eur J Biochem. 1995 Oct 1;233(1):48-54. doi: 10.1111/j.1432-1033.1995.048_1.x.

Abstract

Rex of human T-cell leukemia virus type I (HTLV-I) and Rev of human immunodeficiency virus 1 (HIV-1) are post-transcriptional regulators of viral gene expression. By means of affinity chromatography, we purified an 18-kDa cellular protein that bound to the conserved leucine-motif/activation domain of HTLV-I Rex or HIV-1 Rev. The protein that was purified through a Rev-affinity column was found to bind to Rex immunoprecipitated with anti-Rex IgG from an HTLV-I-producing cell line. We analyzed the purified approximately 18-kDa protein biochemically and identified it as prothymosin alpha. The binding activity of prothymosin alpha to Rev or Rex was completely abolished when the epsilon-amino groups of its lysine residues were chemically modified by N-succinimidyl-3-(4-hydroxy-3,5-diodo- phenyl)propionate. The functional relationship between the nuclear protein prothymosin alpha and Rex-Rev is discussed.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Carrier Proteins / genetics
  • Carrier Proteins / isolation & purification
  • Carrier Proteins / metabolism
  • Cell Line
  • Chromatography, Affinity
  • Gene Products, rev / genetics
  • Gene Products, rev / isolation & purification
  • Gene Products, rev / metabolism*
  • Gene Products, rex / genetics
  • Gene Products, rex / isolation & purification
  • Gene Products, rex / metabolism*
  • HIV-1 / chemistry
  • HIV-1 / genetics
  • HIV-1 / metabolism*
  • Human T-lymphotropic virus 1 / chemistry
  • Human T-lymphotropic virus 1 / genetics
  • Human T-lymphotropic virus 1 / metabolism*
  • Humans
  • Molecular Sequence Data
  • Precipitin Tests
  • Protein Binding
  • Protein Precursors / genetics
  • Protein Precursors / isolation & purification
  • Protein Precursors / metabolism*
  • Sequence Homology, Amino Acid
  • Thymosin / analogs & derivatives*
  • Thymosin / genetics
  • Thymosin / isolation & purification
  • Thymosin / metabolism
  • rev Gene Products, Human Immunodeficiency Virus

Substances

  • Carrier Proteins
  • Gene Products, rev
  • Gene Products, rex
  • Protein Precursors
  • prothymosin alpha
  • rev Gene Products, Human Immunodeficiency Virus
  • Thymosin