TY - JOUR
T1 - Regulation of kinesin activity by phosphorylation of kinesin-associated proteins
AU - McIlvain, James M.
AU - Burkhardt, Janis K.
AU - Hamm-Alvarez, Sarah
AU - Argon, Yair
AU - Sheetz, Michael P.
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 1994/7/22
Y1 - 1994/7/22
N2 - The mechanochemical motor proteins of the kinesin and cytoplasmic dynein families play important roles in microtubule-based intracellular motility. Although movement and distribution of organelles like secretory granules, vesicles, endoplasmic reticulum, and chromosomes depend on the activity of these motor proteins, little is known about the regulation of this movement. We report here that the hyperphosphorylation of components of the kinesin complex by treatment with okadaic acid increases kinesin motor activity at least 2-fold. The stimulation was observed using both a granule motility assay and a microtubule gliding assay, indicating that phosphorylation enhances the activity of the motor itself, rather than the affinity of the motor for membrane organelles. Under stimulatory conditions, three proteins that co-purify with kinesin (with mobilities of 150, 79, and 73 kDa) are consistently hyperphosphorylated. Dephosphorylation of these proteins reduces kinesin activity to basal levels. Therefore, we conclude that kinesin motor activity is directly modulated by the phosphorylation state of kinesin- associated proteins.
AB - The mechanochemical motor proteins of the kinesin and cytoplasmic dynein families play important roles in microtubule-based intracellular motility. Although movement and distribution of organelles like secretory granules, vesicles, endoplasmic reticulum, and chromosomes depend on the activity of these motor proteins, little is known about the regulation of this movement. We report here that the hyperphosphorylation of components of the kinesin complex by treatment with okadaic acid increases kinesin motor activity at least 2-fold. The stimulation was observed using both a granule motility assay and a microtubule gliding assay, indicating that phosphorylation enhances the activity of the motor itself, rather than the affinity of the motor for membrane organelles. Under stimulatory conditions, three proteins that co-purify with kinesin (with mobilities of 150, 79, and 73 kDa) are consistently hyperphosphorylated. Dephosphorylation of these proteins reduces kinesin activity to basal levels. Therefore, we conclude that kinesin motor activity is directly modulated by the phosphorylation state of kinesin- associated proteins.
UR - http://www.scopus.com/inward/record.url?scp=0028306899&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028306899&partnerID=8YFLogxK
M3 - Article
C2 - 8034676
AN - SCOPUS:0028306899
SN - 0021-9258
VL - 269
SP - 19176
EP - 19182
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 29
ER -