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5m5i

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Revision as of 03:33, 16 November 2017

Pseudo-atomic model of microtubule-bound S.pombe kinesin-5 motor domain in the AMPPNP state (based on cryo-electron microscopy experiment): the N-terminus conformation allows formation of a cover neck bundle.

Structural highlights

5m5i is a 3 chain structure with sequence from Bos taurus and Fission yeast. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, , , ,
Gene:	cut7, SPAC25G10.07c (Fission yeast)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[TBA1D_BOVIN] Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain (By similarity). [CUT7_SCHPO] Could be a spindle pole body motor. On transition from G2 to M phase of the cell cycle, the spindle pole body duplicates; the daughter pole bodies seed microtubules which interdigitate to form a short spindle that elongates to span the nucleus at metaphase. Mutations at cut7 block spindle formation. [TBB2B_BOVIN] Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain (By similarity).

Publication Abstract from PubMed

Cut7, the sole kinesin-5 in Schizosaccharomyces pombe, is essential for mitosis. Like other yeast kinesin-5 motors, Cut7 can reverse its stepping direction, by mechanisms that are currently unclear. Here we show that for full-length Cut7, the key determinant of stepping direction is the degree of motor crowding on the microtubule lattice, with greater crowding converting the motor from minus end-directed to plus end-directed stepping. To explain how high Cut7 occupancy causes this reversal, we postulate a simple proximity sensing mechanism that operates via steric blocking. We propose that the minus end-directed stepping action of Cut7 is selectively inhibited by collisions with neighbors under crowded conditions, whereas its plus end-directed action, being less space-hungry, is not. In support of this idea, we show that the direction of Cut7-driven microtubule sliding can be reversed by crowding it with non-Cut7 proteins. Thus, crowding by either dynein microtubule binding domain or Klp2, a kinesin-14, converts Cut7 from net minus end-directed to net plus end-directed stepping. Biochemical assays confirm that the Cut7 N terminus increases Cut7 occupancy by binding directly to microtubules. Direct observation by cryoEM reveals that this occupancy-enhancing N-terminal domain is partially ordered. Overall, our data point to a steric blocking mechanism for directional reversal through which collisions of Cut7 motor domains with their neighbors inhibit their minus end-directed stepping action, but not their plus end-directed stepping action. Our model can potentially reconcile a number of previous, apparently conflicting, observations and proposals for the reversal mechanism of yeast kinesins-5.

Schizosaccharomyces pombe kinesin-5 switches direction using a steric blocking mechanism.,Britto M, Goulet A, Rizvi S, von Loeffelholz O, Moores CA, Cross RA Proc Natl Acad Sci U S A. 2016 Nov 22;113(47):E7483-E7489. Epub 2016 Nov 9. PMID:27834216^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Britto M, Goulet A, Rizvi S, von Loeffelholz O, Moores CA, Cross RA. Schizosaccharomyces pombe kinesin-5 switches direction using a steric blocking mechanism. Proc Natl Acad Sci U S A. 2016 Nov 22;113(47):E7483-E7489. Epub 2016 Nov 9. PMID:27834216 doi:http://dx.doi.org/10.1073/pnas.1611581113

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5m5i"

@@ Line 3: / Line 3: @@
 <StructureSection load='5m5i' size='340' side='right' caption='[[5m5i]], [[Resolution|resolution]] 9.30&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5m5i]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/ ] and [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5M5I OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5M5I FirstGlance]. <br>
+<table><tr><td colspan='2'>[[5m5i]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] and [http://en.wikipedia.org/wiki/Fission_yeast Fission yeast]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5M5I OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5M5I FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ANP:PHOSPHOAMINOPHOSPHONIC+ACID-ADENYLATE+ESTER'>ANP</scene>, <scene name='pdbligand=GDP:GUANOSINE-5-DIPHOSPHATE'>GDP</scene>, <scene name='pdbligand=GTP:GUANOSINE-5-TRIPHOSPHATE'>GTP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=TA1:TAXOL'>TA1</scene></td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">cut7, SPAC25G10.07c ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=284812 Fission yeast])</td></tr>
 <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5m5i FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5m5i OCA], [http://pdbe.org/5m5i PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5m5i RCSB], [http://www.ebi.ac.uk/pdbsum/5m5i PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5m5i ProSAT]</span></td></tr>
 </table>
@@ Line 23: / Line 24: @@
 </StructureSection>
 [[Category: Bos taurus]]
+[[Category: Fission yeast]]
 [[Category: Cross, R A]]
 [[Category: Goulet, A]]

5m5i

From Proteopedia

Revision as of 03:33, 16 November 2017

Pseudo-atomic model of microtubule-bound S.pombe kinesin-5 motor domain in the AMPPNP state (based on cryo-electron microscopy experiment): the N-terminus conformation allows formation of a cover neck bundle.

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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