Control of cell fate by Hsp70: more than an evanescent meeting.
During their lifetime, proteins inevitably expose hydrophobic segments within the polypeptide chains on a molecule's surface, which may be otherwise buried inside the molecules in the proper conformation. This potentially dangerous situation is managed with the aid of the 70-kDa heat shock proteins (Hsp70s) and other molecular chaperones. Although a major function of Hsp70 is assisting in efficient folding of anonymous proteins in unfolded states, recent studies have revealed that Hsp70 plays a variety of specific roles, sometimes deciding the cell fate. These multiple activities are based on the specific binding of Hsp70 to proteins in native states, which regulate cell growth and/or death. It is now well recognized that unfolding of some proteins may cause serious diseases, especially those associated with neurodegeneration, such as Alzheimer's disease. It is suggested that Hsp70 might be a potential drug against these diseases, but caution should be taken because Hsp70 exerts multiple effects by binding to specific proteins.
Morishima
Nobuhiro
N
Bioarchitect Research Group, RIKEN (the Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198. morishim@riken.jp
D000251:Adenosine Triphosphatases / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics / Q000378:metabolism; D019143:Evolution, Molecular; D018840:HSP70 Heat-Shock Proteins / Q000502:physiology*; D018832:Molecular Chaperones / Q000502:physiology; D017510:Protein Folding; D029701:Saccharomyces cerevisiae Proteins
D018840:HSP70 Heat-Shock Proteins; D018832:Molecular Chaperones; D029701:Saccharomyces cerevisiae Proteins; C037725:SCEI protein, S cerevisiae; D015252:Deoxyribonucleases, Type II Site-Specific; D000251:Adenosine Triphosphatases