title: A comparison of the ability of XMAP215 and tau to inhibit the microtubule destabilizing activity of XKCM1.
abstract: During mitosis, microtubules not only grow fast, but also have a high rate of catastrophe. This is achieved in part by the activity of the MAP, XMAP215, which can stimulate the growth rate of microtubules without fully inhibiting the function of the catastrophe-kinesin XKCM1. We do not know whether this activity is particular to XMAP215, or is a general property of all MAPs. Here, we compare the activities of XMAP215 with the neuronal MAP tau, in opposing the destabilizing activity of the non-conventional kinesin XKCM1. We show that tau is a much more potent inhibitor of XKCM1 than XMAP215. Because tau completely suppresses XKCM1 activity, even at low concentrations, the combination of tau and XKCM1 is unable to generate mitotic microtubule dynamics.
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany.
authors.forename: Tim L
authors.initials: TL
authors.lastname: Noetzel
authors.forename: David N
authors.initials: DN
authors.lastname: Drechsel
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Hyman
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Kinoshita
mesh_terms: D005453:Fluorescence; D016547:Kinesins / Q000037:antagonists & inhibitors*; D008869:Microtubule-Associated Proteins / Q000378:metabolism* / Q000494:pharmacology; D008870:Microtubules / Q000378:metabolism* / Q000502:physiology; D008938:Mitosis / Q000502:physiology*; D008954:Models, Biological; D013997:Time Factors; D014404:Tubulin / Q000378:metabolism; D029867:Xenopus Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism* / Q000494:pharmacology; D016875:tau Proteins / Q000378:metabolism* / Q000494:pharmacology
chemical_list: C486738:CKAP5 protein, Xenopus; C088335:KIF11 protein, Xenopus; D008869:Microtubule-Associated Proteins; D014404:Tubulin; D029867:Xenopus Proteins; D016875:tau Proteins; D016547:Kinesins