Novel heterotrimeric kinesin-related protein purified from sea urchin eggs.
Kinesin heavy chain and kinesin-related polypeptides (KRPs) comprise a family of motor proteins with diverse intracellular transport functions. Using pan-kinesin peptide antibodies that react with these proteins, we have previously purified from sea urchin eggs a trimeric microtubule-binding and bundling protein, KRP (85/95) (ref. 8) comprising subunits of M(r) 115,000 (115K), 95K and 85K. We report here that kinesin-related genes encode the 85K and 95K subunits, and that the protein can be immunoprecipitated from cytosol as a trimeric complex using an 85K monoclonal antibody. We also find that purified KRP(85/95) directs movements towards the 'plus' ends of microtubules. To our knowledge, this protein is the first kinesin-related motor to be purified from its natural host cell in a native multimeric state.
Cole
D G
DG
Section of Molecular and Cellular Biology, University of California, Davis 95616.
Chinn
S W
SW
Wedaman
K P
KP
Hall
K
K
Vuong
T
T
Scholey
J M
JM
D000595:Amino Acid Sequence; D000818:Animals; D002135:Calcium-Binding Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000502:physiology; D003001:Cloning, Molecular; D004527:Egg Proteins / Q000737:chemistry / Q000302:isolation & purification*; D016547:Kinesins / Q000737:chemistry*; D008870:Microtubules / Q000502:physiology; D008969:Molecular Sequence Data; D009124:Muscle Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000502:physiology; D009865:Oocytes / Q000737:chemistry*; D012617:Sea Urchins
D002135:Calcium-Binding Proteins; D004527:Egg Proteins; D009124:Muscle Proteins; C074152:kinesin-II; D016547:Kinesins