Glucose regulated proteins 78 and 75 bind to the receptor for hyaluronan mediated motility in interphase microtubules.
The receptor for hyaluronan mediated motility (RHAMM), which is a hyaluronan-binding protein, is a centrosomal and microtubal protein. Here, we have identified two RHAMM-binding proteins, glucose regulated protein (GRP) 78 and GRP75, using co-immunoprecipitation analysis. These two proteins directly bound to glutathione-S-transferase-RHAMM fusion proteins. By double immunostaining, GRP78 and GRP75 colocalized with RHAMM in interphase microtubules, but were separated in mitotic spindles. Prevention of microtubule polymerization by TN-16 and vincristine sulfate induced RHAMM overexpression without a significant change in GRP78/75. Taken together, GRP78/75 and RHAMM complexes may stabilize microtubules in the interphase, associated with a downregulation of RHAMM. These results reveal a new biochemical activity of RHAMM.
Kuwabara
Hiroko
H
Department of Pathology, Osaka Medical College, 2-7, Takatsuki, Osaka 569-8686, Japan. pa2020@art.osaka-med.ac.jp
Yoneda
Masahiko
M
Hayasaki
Hana
H
Nakamura
Toshiya
T
Mori
Hiroshi
H
D045744:Cell Line, Tumor; D000091342:Endoplasmic Reticulum Chaperone BiP; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism*; D007399:Interphase; D019169:Jurkat Cells; D016393:Lymphoma, B-Cell / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D018832:Molecular Chaperones / Q000378:metabolism*; D011485:Protein Binding
D000091342:Endoplasmic Reticulum Chaperone BiP; D016326:Extracellular Matrix Proteins; D018840:HSP70 Heat-Shock Proteins; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D018960:Hyaluronan Receptors; D008565:Membrane Proteins; D018832:Molecular Chaperones; C018551:glucose-regulated proteins; C098946:hyaluronan-mediated motility receptor