Heat shock proteins induce pores in membranes.
Human heat shock protein (hsp) 70 and bacterial protein groEL promote leakage of calcein from liposomes induced by human serum albumin signal peptide, by S. aureus alpha toxin or by diphtheria toxin. Hsp 70 and groEL, as well as two mycobacterial homologues hsp 71 and hsp 65, induce ion conducting pores across planar lipid bilayers at low or neutral pH. It is concluded that hsp induce pores in membranes and that this may contribute to their action within cells.
Alder
G M
GM
Department of Cellular and Molecular Sciences, St George's Hospital Medical School, London.
Austen
B M
BM
Bashford
C L
CL
Mehlert
A
A
Pasternak
C A
CA
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000494:pharmacology*; D002463:Cell Membrane Permeability / Q000187:drug effects / Q000502:physiology; D018834:Chaperonin 60; D004357:Drug Synergism; D005452:Fluoresceins / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D015640:Ion Channel Gating / Q000187:drug effects* / Q000502:physiology; D008081:Liposomes; D008969:Molecular Sequence Data; D021382:Protein Sorting Signals / Q000138:chemical synthesis / Q000494:pharmacology; D010738:Type C Phospholipases / Q000494:pharmacology
D001426:Bacterial Proteins; D018834:Chaperonin 60; D005452:Fluoresceins; D006360:Heat-Shock Proteins; D008081:Liposomes; D021382:Protein Sorting Signals; D010738:Type C Phospholipases; C007740:fluorexon