Proteomics shows Hsp70 does not bind peptide sequences indiscriminately in vivo

Michael E. Grossmann, Benjamin J. Madden, Fan Gao, Yuan Ping Pang, John E. Carpenter, Daniel McCormick, Charles Y.F. Young

Research output: Contribution to journalArticle

38 Scopus citations

Abstract

Heat shock protein 70 (Hsp70) binds peptide and has several functions that include protein folding, protein trafficking, and involvement with immune function. However, endogenous Hsp70-binding peptides had not previously been identified. Therefore, we eluted and identified several hundred endogenously bound peptides from Hsp70 using liquid chromatography ion trap mass spectrophotometry (LC-ITMS). Our work shows that the peptides are capable of binding Hsp70 as previously described. They are generally 8-26 amino acids in length and correspond to specific regions of many proteins. Through computationally assisted analysis of peptides eluted from Hsp70 we determined variable amino acid sequences, including a 5 amino acid core sequence that Hsp70 favorably binds. We also developed a computer algorithm that predicts Hsp70 binding within proteins. This work helps to define what peptides are bound by Hsp70 in vivo and suggests that Hsp70 facilitates peptide selection by aiding a funneling mechanism that is flexible but allows only a limited number of peptides to be processed.

Original languageEnglish (US)
Pages (from-to)108-117
Number of pages10
JournalExperimental Cell Research
Volume297
Issue number1
DOIs
StatePublished - Jul 1 2004

    Fingerprint

Keywords

  • Binding
  • Heat shock proteins
  • Hsp70
  • MHC and processing
  • Mass spectrophotometry
  • Peptides

ASJC Scopus subject areas

  • Cell Biology

Cite this