Kinesin light chain-independent function of the Kinesin heavy chain in cytoplasmic streaming and posterior localisation in the Drosophila oocyte.
Microtubules and the Kinesin heavy chain, the force-generating component of the plus end-directed microtubule motor Kinesin I are required for the localisation of oskar mRNA to the posterior pole of the Drosophila oocyte, an essential step in the determination of the anteroposterior axis. We show that the Kinesin heavy chain is also required for the posterior localisation of Dynein, and for all cytoplasmic movements within the oocyte. Furthermore, the KHC localises transiently to the posterior pole in an oskar mRNA-independent manner. Surprisingly, cytoplasmic streaming still occurs in kinesin light chain null mutants, and both oskar mRNA and Dynein localise to the posterior pole. Thus, the Kinesin heavy chain can function independently of the light chain in the oocyte, indicating that it associates with its cargoes by a novel mechanism.
Palacios
Isabel M
IM
Wellcome Trust/Cancer Research UK Institute and Department of Genetics, University of Cambridge, Tennis Court Road, UK.
St Johnston
Daniel
D
D000818:Animals; D001692:Biological Transport / Q000502:physiology; D002352:Carrier Proteins / Q000378:metabolism; D016764:Cell Polarity; D003595:Cytoplasmic Streaming / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics / Q000502:physiology*; D004398:Dyneins / Q000378:metabolism; D017403:In Situ Hybridization; D016547:Kinesins / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D009866:Oogenesis / Q000502:physiology; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism
D002352:Carrier Proteins; D029721:Drosophila Proteins; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; C091675:osk protein, Drosophila; C417671:syd protein, Drosophila; C069927:stau protein, Drosophila; D004398:Dyneins; D016547:Kinesins