1f9v: Difference between revisions

Revision as of 13:36, 21 February 2008

CRYSTAL STRUCTURES OF MUTANTS REVEAL A SIGNALLING PATHWAY FOR ACTIVATION OF THE KINESIN MOTOR ATPASE

OverviewOverview

Molecular motors move along actin or microtubules by rapidly hydrolyzing ATP and undergoing changes in filament-binding affinity with steps of the nucleotide hydrolysis cycle. It is generally accepted that motor binding to its filament greatly increases the rate of ATP hydrolysis, but the structural changes in the motor associated with ATPase activation are not known. To identify the conformational changes underlying motor movement on its filament, we solved the crystal structures of three kinesin mutants that decouple nucleotide and microtubule binding by the motor, and block microtubule-activated, but not basal, ATPase activity. Conformational changes in the structures include a disordered loop and helices in the switch I region and a visible switch II loop, which is disordered in wild-type structures. Switch I moved closer to the bound nucleotide in two mutant structures, perturbing water-mediated interactions with the Mg2+. This could weaken Mg2+ binding and accelerate ADP release to activate the motor ATPASE: The structural changes we observe define a signaling pathway within the motor for ATPase activation that is likely to be essential for motor movement on microtubules.

About this StructureAbout this Structure

1F9V is a Single protein structure of sequence from Saccharomyces cerevisiae with and as ligands. Full crystallographic information is available from OCA.

ReferenceReference

A structural pathway for activation of the kinesin motor ATPase., Yun M, Zhang X, Park CG, Park HW, Endow SA, EMBO J. 2001 Jun 1;20(11):2611-8. PMID:11387196

Page seeded by OCA on Thu Feb 21 12:36:26 2008

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OCA

@@ Line 1: / Line 1: @@
-[[Image:1f9v.gif|left|200px]]<br /><applet load="1f9v" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:1f9v.gif|left|200px]]<br /><applet load="1f9v" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="1f9v, resolution 1.3&Aring;" />
 '''CRYSTAL STRUCTURES OF MUTANTS REVEAL A SIGNALLING PATHWAY FOR ACTIVATION OF THE KINESIN MOTOR ATPASE'''<br />
 ==Overview==
-Molecular motors move along actin or microtubules by rapidly hydrolyzing, ATP and undergoing changes in filament-binding affinity with steps of the, nucleotide hydrolysis cycle. It is generally accepted that motor binding, to its filament greatly increases the rate of ATP hydrolysis, but the, structural changes in the motor associated with ATPase activation are not, known. To identify the conformational changes underlying motor movement on, its filament, we solved the crystal structures of three kinesin mutants, that decouple nucleotide and microtubule binding by the motor, and block, microtubule-activated, but not basal, ATPase activity. Conformational, changes in the structures include a disordered loop and helices in the, switch I region and a visible switch II loop, which is disordered in, wild-type structures. Switch I moved closer to the bound nucleotide in two, mutant structures, perturbing water-mediated interactions with the Mg2+., This could weaken Mg2+ binding and accelerate ADP release to activate the, motor ATPASE: The structural changes we observe define a signaling pathway, within the motor for ATPase activation that is likely to be essential for, motor movement on microtubules.
+Molecular motors move along actin or microtubules by rapidly hydrolyzing ATP and undergoing changes in filament-binding affinity with steps of the nucleotide hydrolysis cycle. It is generally accepted that motor binding to its filament greatly increases the rate of ATP hydrolysis, but the structural changes in the motor associated with ATPase activation are not known. To identify the conformational changes underlying motor movement on its filament, we solved the crystal structures of three kinesin mutants that decouple nucleotide and microtubule binding by the motor, and block microtubule-activated, but not basal, ATPase activity. Conformational changes in the structures include a disordered loop and helices in the switch I region and a visible switch II loop, which is disordered in wild-type structures. Switch I moved closer to the bound nucleotide in two mutant structures, perturbing water-mediated interactions with the Mg2+. This could weaken Mg2+ binding and accelerate ADP release to activate the motor ATPASE: The structural changes we observe define a signaling pathway within the motor for ATPase activation that is likely to be essential for motor movement on microtubules.
 ==About this Structure==
-F9V is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with MG and ADP as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1F9V OCA].
+F9V is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with <scene name='pdbligand=MG:'>MG</scene> and <scene name='pdbligand=ADP:'>ADP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1F9V OCA].
 ==Reference==
@@ Line 13: / Line 13: @@
 [[Category: Saccharomyces cerevisiae]]
 [[Category: Single protein]]
-[[Category: Endow, S.A.]]
+[[Category: Endow, S A.]]
-[[Category: Park, C.G.]]
+[[Category: Park, C G.]]
-[[Category: Park, H.W.]]
+[[Category: Park, H W.]]
 [[Category: Yun, M.]]
 [[Category: Zhang, X.]]
@@ Line 25: / Line 25: @@
 [[Category: motor protein]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 14:44:43 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:36:26 2008''