title: A non-mitotic CENP-E homolog in Dictyostelium discoideum with slow motor activity.
abstract: Kinesins are ATP-dependent molecular motors that mediate unidirectional intracellular transport along microtubules. Dictyostelium discoideum has 13 different kinesin isoforms including two members of the kinesin-7 family, Kif4 and Kif11. While Kif4 is structurally and functionally related to centromere-associated CENP-E proteins involved in the transport of chromosomes to the poles during mitosis, the function of the unusually short CENP-E variant Kif11 is unclear. Here we show that orthologs of short CENP-E variants are present in plants and fungi, and analyze functional properties of the Dictyostelium CENP-E version, Kif11. Gene knockout mutants reveal that Kif11 is not required for mitosis or development. Imaging of GFP-labeled Kif11 expressing Dictyostelium cells indicates that Kif11 is a plus-end directed motor that accumulates at microtubule plus ends. By multiple motor gliding assays, we show that Kif11 moves with an average velocity of 38nm/s, thus defining Kif11 as a very slow motor. The activity of the Kif11 motor appears to be modulated via interactions with the non-catalytic tail region. Our work highlights a subclass of kinesin-7-like motors that function outside of a role in mitosis.
authors: Institute for Anatomy and Cell Biology, Ludwig Maximilian University of Munich, Schillerstr. 42, 80336 Munich, Germany.
authors: Süleyman
authors: S
authors: Kösem
authors: Zeynep
authors: Z
authors: Ökten
authors: Thi-Hieu
authors: TH
authors: Ho
authors: Gudrun
authors: G
authors: Trommler
authors: Michael P
authors: MP
authors: Koonce
authors: Matthias
authors: M
authors: Samereier
authors: Annette
authors: A
authors: Müller-Taubenberger
mesh_terms: D000251:Adenosine Triphosphatases / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D004023:Dictyostelium / Q000235:genetics / Q000378:metabolism*; D055786:Gene Knockout Techniques; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D016547:Kinesins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008938:Mitosis; D010802:Phylogeny; D017433:Protein Structure, Secondary
chemical_list: D002868:Chromosomal Proteins, Non-Histone; C068688:centromere protein E; D049452:Green Fluorescent Proteins; D000251:Adenosine Triphosphatases; D016547:Kinesins