Publication Date:
2003-12-06
Description:
Kinesin is a double-headed motor protein that moves along microtubules in 8-nanometer steps. Two broad classes of model have been invoked to explain kinesin movement: hand-over-hand and inchworm. In hand-over-hand models, the heads exchange leading and trailing roles with every step, whereas no such exchange is postulated for inchworm models, where one head always leads. By measuring the stepwise motion of individual enzymes, we find that some kinesin molecules exhibit a marked alternation in the dwell times between sequential steps, causing these motors to "limp" along the microtubule. Limping implies that kinesin molecules strictly alternate between two different conformations as they step, indicative of an asymmetric, hand-over-hand mechanism.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1523256/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1523256/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Asbury, Charles L -- Fehr, Adrian N -- Block, Steven M -- R01 GM051453/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2003 Dec 19;302(5653):2130-4. Epub 2003 Dec 4.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/14657506" target="_blank"〉PubMed〈/a〉
Keywords:
Adenosine Triphosphate/metabolism
;
Animals
;
Computer Simulation
;
Decapodiformes/enzymology
;
Dimerization
;
Drosophila Proteins/chemistry/physiology
;
Drosophila melanogaster/*enzymology
;
Humans
;
Kinesin/*chemistry/*physiology
;
Kinetics
;
Microspheres
;
Microtubules/metabolism
;
Models, Molecular
;
Molecular Motor Proteins/*chemistry/*physiology
;
Movement
;
Protein Conformation
;
Protein Structure, Secondary
;
Protein Structure, Tertiary
;
Recombinant Proteins/chemistry
;
Rotation
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
