title: New Insights into the Coupling between Microtubule Depolymerization and ATP Hydrolysis by Kinesin-13 Protein Kif2C.
abstract: Kinesin-13 proteins depolymerize microtubules in an ATP hydrolysis-dependent manner. The coupling between these two activities remains unclear. Here, we first studied the role of the kinesin-13 subfamily-specific loop 2 and of the KVD motif at the tip of this loop. Shortening the loop, the lysine/glutamate interchange and the additional Val to Ser substitution all led to Kif2C mutants with decreased microtubule-stimulated ATPase and impaired depolymerization capability. We rationalized these results based on a structural model of the Kif2C-ATP-tubulin complex derived from the recently determined structures of kinesin-1 bound to tubulin. In this model, upon microtubule binding Kif2C undergoes a conformational change governed in part by the interaction of the KVD motif with the tubulin interdimer interface. Second, we mutated to an alanine the conserved glutamate residue of the switch 2 nucleotide binding motif. This mutation blocks motile kinesins in a post-conformational change state and inhibits ATP hydrolysis. This Kif2C mutant still depolymerized microtubules and yielded complexes of one Kif2C with two tubulin heterodimers. These results demonstrate that the structural change of Kif2C-ATP upon binding to microtubule ends is sufficient for tubulin release, whereas ATP hydrolysis is not required. Overall, our data suggest that the conformation reached by kinesin-13s upon tubulin binding is similar to that of tubulin-bound, ATP-bound, motile kinesins but that this conformation is adapted to microtubule depolymerization.
authors.affiliation: From the Institute of Protein Research, Tongji University, Shanghai 200092, China, the Institute for Integrative Biology of the Cell, CEA, CNRS, Université Paris-Sud, Gif-sur-Yvette 91198, France, and.
authors.forename: Weiyi
authors.initials: W
authors.lastname: Wang
authors.affiliation: From the Institute of Protein Research, Tongji University, Shanghai 200092, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Shen
authors.affiliation: the Institute for Integrative Biology of the Cell, CEA, CNRS, Université Paris-Sud, Gif-sur-Yvette 91198, France, and the From CEA, Institut de Biologie et de la Technologies de Saclay (iBiTecS), Gif-sur-Yvette 91191, France.
authors.forename: Raphael
authors.initials: R
authors.lastname: Guerois
authors.affiliation: From the Institute of Protein Research, Tongji University, Shanghai 200092, China.
authors.forename: Fuming
authors.initials: F
authors.lastname: Zhang
authors.affiliation: From the Institute of Protein Research, Tongji University, Shanghai 200092, China.
authors.forename: Hureshitanmu
authors.initials: H
authors.lastname: Kuerban
authors.affiliation: From the Institute of Protein Research, Tongji University, Shanghai 200092, China.
authors.forename: Yuncong
authors.initials: Y
authors.lastname: Lv
authors.affiliation: the Institute for Integrative Biology of the Cell, CEA, CNRS, Université Paris-Sud, Gif-sur-Yvette 91198, France, and benoit.gigant@i2bc.paris-saclay.fr.
authors.forename: Benoît
authors.initials: B
authors.lastname: Gigant
authors.affiliation: the Institute for Integrative Biology of the Cell, CEA, CNRS, Université Paris-Sud, Gif-sur-Yvette 91198, France, and marcel.knossow@i2bc.paris-saclay.fr.
authors.forename: Marcel
authors.initials: M
authors.lastname: Knossow
authors.affiliation: From the Institute of Protein Research, Tongji University, Shanghai 200092, China, chunguangwang@tongji.edu.cn.
authors.forename: Chunguang
authors.initials: C
authors.lastname: Wang
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019943:Amino Acid Substitution / Q000235:genetics; D001665:Binding Sites; D018360:Crystallography, X-Ray; D006801:Humans; D006868:Hydrolysis; D016547:Kinesins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D012694:Serine / Q000235:genetics; D013329:Structure-Activity Relationship; D014404:Tubulin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014633:Valine / Q000235:genetics
chemical_list: C091489:KIF2C protein, human; D014404:Tubulin; D012694:Serine; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D016547:Kinesins; D014633:Valine
keywords: ATPase; conformational change; kinesin; microtubule; molecular motor