Monomer arrangement in HSP90 dimer as determined by decoration with N and C-terminal region specific antibodies.
Electron microscopy using the low-angle rotary shadowing replica method showed that the HSP90 dimer consists of four globular domains aligning in a tandem fashion. When decorated with two monoclonal antibodies against epitopes mapped on the N-terminal region of HSP90, these antibodies bound to both ends of the HSP90 dimer. A C-terminal region specific antibody was shown to bind to the side of HSP90. These results support a model for HSP90 dimer whereby two HSP90 monomers are arranged in an antiparallel fashion and dimerize through the C-terminal domain. Treatment of HSP90 at elevated temperatures or with ATP at room temperature, though not with ADP, induces molecular transformation of the linear HSP90 dimer into an O-ring-shaped structure.
Maruya
M
M
Department of Cell Biology, The Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, 113-8613, Japan.
Sameshima
M
M
Nemoto
T
T
Yahara
I
I
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000276:immunology* / Q000648:ultrastructure; D001426:Bacterial Proteins; D019281:Dimerization; D000939:Epitopes / Q000276:immunology; D018841:HSP90 Heat-Shock Proteins / Q000276:immunology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D011485:Protein Binding / Q000276:immunology; D012260:Ribonucleases / Q000276:immunology* / Q000648:ultrastructure; D013696:Temperature
D000911:Antibodies, Monoclonal; D001426:Bacterial Proteins; D000939:Epitopes; D018841:HSP90 Heat-Shock Proteins; D000255:Adenosine Triphosphate; D012260:Ribonucleases; C019760:Bacillus amyloliquefaciens ribonuclease