title: Effects of α-tubulin K40 acetylation and detyrosination on kinesin-1 motility in a purified system.
abstract: Long-range transport in cells is achieved primarily through motor-based transport along a network of microtubule tracks. Targeted transport by kinesin motors can be correlated with posttranslational modifications (PTMs) of the tubulin subunits in specific microtubules. To directly examine the influence of specific PTMs on kinesin-1 motility, we generated tubulin subunits that were either enriched in or lacking acetylation of α-tubulin lysine 40 (K40) or detyrosination of the α-tubulin C-terminal tail. We show that K40 acetylation does not result in significant changes in kinesin-1's landing rate or motility parameters (velocity and run length) across experimental conditions. In contrast, detyrosination causes a moderate increase in kinesin-1's landing rate. The fact that the effects of detyrosination are dampened by prior K40 acetylation indicates that the combination of PTMs may be an important aspect of the functional output of microtubule heterogeneity. Importantly, our results indicate that the moderate influences that single PTMs have on kinesin-1 in vitro do not explain the strong correlation between specific PTMs and kinesin-1 transport in cells. Thus, additional mechanisms for regulating kinesin-1 transport in cells must be explored in future work.
authors.affiliation: Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan. Electronic address: nehakaul@email.unc.edu.
authors.forename: Neha
authors.initials: N
authors.lastname: Kaul
authors.affiliation: Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan.
authors.forename: Virupakshi
authors.initials: V
authors.lastname: Soppina
authors.affiliation: Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan.
authors.forename: Kristen J
authors.initials: KJ
authors.lastname: Verhey
mesh_terms: D000107:Acetylation; D000818:Animals; D002417:Cattle; D006367:HeLa Cells; D006801:Humans; D016547:Kinesins / Q000378:metabolism*; D008239:Lysine / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism; D021381:Protein Transport; D051381:Rats; D014404:Tubulin / Q000737:chemistry / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D014404:Tubulin; D014443:Tyrosine; D016547:Kinesins; D008239:Lysine