title: Shaping fission yeast cells by rerouting actin-based transport on microtubules.
abstract: Kinesins and myosins transport cargos to specific locations along microtubules and actin filaments, respectively. The relative contribution of the two transport systems for cell polarization varies extensively in different cell types, with some cells relying exclusively on actin-based transport while others mainly use microtubules. Using fission yeast, we asked whether one transport system can substitute for the other. In this organism, microtubules and actin cables both contribute to polarized growth by transporting cargos to cell poles, but with distinct roles: microtubules transport landmarks to label cell poles for growth and actin assembly but do not directly contribute to the growth process [1]. Actin cables serve as tracks for myosin V delivery of growth vesicles to cell poles [2-4]. We engineered a chimera between the motor domain of the kinesin 7 Tea2 and the globular tail of the myosin V Myo52, which we show transports Ypt3, a myosin cargo receptor, to cell poles along microtubules. Remarkably, this chimera restores polarized growth and viability to cells lacking actin cables. It also bypasses the normal microtubule-dependent marking of cell poles for polarized growth, but not for other functions. Thus, a synthetic motor protein successfully redirects cargos along a distinct cytoskeletal route.
authors.affiliation: Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland.
authors.forename: Libera
authors.initials: L
authors.lastname: Lo Presti
authors.forename: Sophie G
authors.initials: SG
authors.lastname: Martin
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism*; D000199:Actins / Q000378:metabolism; D002455:Cell Division; D016764:Cell Polarity; D005456:Fluorescent Dyes / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism*; D024701:Myosin Type V / Q000378:metabolism; D009218:Myosins / Q000378:metabolism; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D012568:Schizosaccharomyces / Q000166:cytology / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism; D022142:Secretory Vesicles / Q000378:metabolism*; D020691:rab GTP-Binding Proteins / Q000378:metabolism
chemical_list: D000199:Actins; D005456:Fluorescent Dyes; D008869:Microtubule-Associated Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; C415481:Tea2 protein, S pombe; C075976:ypt3 protein, S pombe; C554097:Myo52 protein, S pombe; D024701:Myosin Type V; D009218:Myosins; D020691:rab GTP-Binding Proteins