Functional requirement of p23 and Hsp90 in telomerase complexes

Shawn E. Holt, Dara L. Aisner, Joseph Baur, Valerie M. Tesmer, Marife Dy, Michel Ouellette, James B. Trager, Gregg B. Morin, David O. Toft, Jerry W. Shay, Woodring E. Wright, Michael A. White

Research output: Contribution to journalArticlepeer-review

481 Scopus citations


Most normal human diploid cells have no detectable telomerase; however, expression of the catalytic subunit of telomerase is sufficient to induce telomerase activity and, in many cases, will bypass normal senescence. We and others have previously demonstrated in vitro assembly of active telomerase by combining the purified RNA component with the reverse transcriptase catalytic component synthesized in rabbit reticulocyte extract. Here we show that assembly of active telomerase from in vitro-synthesized components requires the contribution of proteins present in reticulocyte extracts. We have identified the molecular chaperones p23 and Hsp90 as proteins that bind to the catalytic subunit of telomerase. Blockade of this interaction inhibits assembly of active telomerase in vitro. Also, a significant fraction of active telomerase from cell extracts is associated with p23 and Hsp90. Consistent with in vitro results, inhibition of Hsp90 function in cells blocks assembly of active telomerase. To our knowledge, p23 and Hsp90 are the first telomerase-associated proteins demonstrated to contribute to telomerase activity.

Original languageEnglish (US)
Pages (from-to)817-826
Number of pages10
JournalGenes and Development
Issue number7
StatePublished - Apr 1 1999


  • Cancer
  • Chaperones
  • Senescence
  • Telomerase
  • Telomeres

ASJC Scopus subject areas

  • Genetics
  • Developmental Biology


Dive into the research topics of 'Functional requirement of p23 and Hsp90 in telomerase complexes'. Together they form a unique fingerprint.

Cite this