Heat-shock protein 60 translocates to the surface of apoptotic cells and differentiated megakaryocytes and stimulates phagocytosis

Yaw Chong Goh, Celestial T. Yap, Bao Hua Huang, Andrew D. Cronshaw, Bernard P. Leung, Paul B. S. Lai, Simon P. Hart, Ian Dransfield, James A. Ross

Research output: Contribution to journalArticlepeer-review

Abstract

Heat-shock protein 60 (Hsp60) is a highly conserved stress protein which has chaperone functions in prokaryotes and mammalian cells. Hsp60 is associated with the mitochondria and the plasma membrane through phosphorylation by protein kinase A, and is incorporated into lipid membranes as a protein-folding chaperone. Its diverse intracellular chaperone functions include the secretion of proteins where it maintains the conformation of precursors and facilitates their translocation through the plasma membrane. We report here that Hsp60 is concentrated in apoptotic membrane blebs and translocates to the surface of cells undergoing apoptosis. Hsp60 is also enriched in platelets derived from terminally differentiated megakaryocytes and expressed at the surface of senescent platelets. Furthermore, the exposure of monocytic U937 cells to Hsp60 enhanced their phagocytic activity. Our results suggests that externalized Hsp60 in apoptotic cells and senescent platelets influences events subsequent to apoptosis, such as the clearance of apoptotic cells by phagocytes.

Original languageEnglish
Pages (from-to)1581-1592
Number of pages12
JournalCellular and Molecular Life Sciences
Volume68
Issue number9
Early online date16 Oct 2010
DOIs
Publication statusPublished - 30 May 2011

Keywords

  • Hsp60
  • Apoptosis
  • Translocation
  • Platelets
  • Phagocytosis

Cite this