Heat shock protein 90 mediates protein-protein interactions between human aminoacyl-tRNA synthetases

Jeongwoo Kang, Taeho Kim, Young Gyu Ko, Seung Bae Rho, Sang Gyu Park, Min Jung Kim, Ho Jeong Kwon, Sunghoon Kim

Research output: Contribution to journalArticlepeer-review

30 Citations (Scopus)


Heat shock protein 90 (hsp90) is a molecular chaperone responsible for protein folding and maturation in vivo. Interaction of hsp90 with human glutamyl-prolyl-tRNA synthetase (EPRS) was found by genetic screening, co-immunoprecipitation, and in vitro binding experiments. This interaction was sensitive to the hsp90 inhibitor, geldanamycin, and also ATP, suggesting thai the chaperone activity of hsp90 is required for interaction with EPRS. Interaction of EPRS with hsp90 was targeted to the region of three tandem repeats linking the two catalytic domains of EPRS that is also responsible for the interaction with isoleucyl-tRNA synthetase (IRS). Interaction of EPRS and IRS also depended on the activity of hsp90, implying that their association was mediated by hsp90. EPRS and IRS form a macromolecular protein complex with at least six other tRNA synthetases and three cofactors, hsp90 preferentially binds to most of the complex-forming enzymes rather than those that are not found in the complex. In addition, inactivation of hsp90 interfered with the in vivo incorporation of the nascent aminoacyl-tRNA synthetases into the multi-ARS complex. Thus, hsp90 appears to mediate protein-protein interactions of mammalian tRNA synthetases.

Original languageEnglish
Pages (from-to)31682-31688
Number of pages7
JournalJournal of Biological Chemistry
Issue number41
Publication statusPublished - 2000 Oct 13
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'Heat shock protein 90 mediates protein-protein interactions between human aminoacyl-tRNA synthetases'. Together they form a unique fingerprint.

Cite this