title: Transport of fungal RAB11 secretory vesicles involves myosin-5, dynein/dynactin/p25, and kinesin-1 and is independent of kinesin-3.
abstract: Hyphal tip cells of the fungusAspergillus nidulansare useful for studying long-range intracellular traffic. Post-Golgi secretory vesicles (SVs) containing the RAB11 orthologue RabE engage myosin-5 as well as plus end- and minus end-directed microtubule motors, providing an experimental system with which to investigate the interplay between microtubule and actin motors acting on the same cargo. By exploiting the fact that depolymerization of F-actin unleashes SVs focused at the apex by myosin-5 to microtubule-dependent motors, we establish that the minus end-directed transport of SVs requires the dynein/dynactin supercomplex. This minus end-directed transport is largely unaffected by genetic ablation of the Hook complex adapting early endosomes (EEs) to dynein but absolutely requires p25 in dynactin. Thus dynein recruitment to two different membranous cargoes, namely EEs and SVs, requires p25, highlighting the importance of the dynactin pointed-end complex to scaffold cargoes. Finally, by studying the behavior of SVs and EEs in null and rigor mutants of kinesin-3 and kinesin-1 (UncA and KinA, respectively), we demonstrate that KinA is the major kinesin mediating the anterograde transport of SVs. Therefore SVs arrive at the apex ofA. nidulansby anterograde transport involving cooperation of kinesin-1 with myosin-5 and can move away from the apex powered by dynein.
authors.affiliation: Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid 28040, Spain penalva@cib.csic.es.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Peñalva
authors.affiliation: Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4799.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4799.
authors.forename: Xin
authors.initials: X
authors.lastname: Xiang
authors.affiliation: Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid 28040, Spain.
authors.forename: Areti
authors.initials: A
authors.lastname: Pantazopoulou
mesh_terms: D000199:Actins / Q000378:metabolism; D001233:Aspergillus nidulans / Q000378:metabolism; D001692:Biological Transport; D000072159:Dynactin Complex / Q000378:metabolism; D004398:Dyneins / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism; D005656:Fungal Proteins / Q000378:metabolism; D016547:Kinesins / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D020409:Molecular Motor Proteins / Q000378:metabolism*; D009218:Myosins / Q000378:metabolism; D021381:Protein Transport / Q000502:physiology; D022142:Secretory Vesicles / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000378:metabolism*
chemical_list: D000199:Actins; D000072159:Dynactin Complex; D005656:Fungal Proteins; D008869:Microtubule-Associated Proteins; D020409:Molecular Motor Proteins; D009218:Myosins; D004398:Dyneins; D016547:Kinesins; D020691:rab GTP-Binding Proteins