title: Transportation of Aspergillus nidulans Class III and V Chitin Synthases to the Hyphal Tips Depends on Conventional Kinesin.
abstract: Cell wall formation and maintenance are crucial for hyphal morphogenesis. In many filamentous fungi, chitin is one of the main structural components of the cell wall. Aspergillus nidulans ChsB, a chitin synthase, and CsmA, a chitin synthase with a myosin motor-like domain (MMD) at its N-terminus, both localize predominantly at the hyphal tip regions and at forming septa. ChsB and CsmA play crucial roles in polarized hyphal growth in A. nidulans. In this study, we investigated the mechanism by which CsmA and ChsB accumulate at the hyphal tip in living hyphae. Deletion of kinA, a gene encoding conventional kinesin (kinesin-1), impaired the localization of GFP-CsmA and GFP-ChsB at the hyphal tips. The transport frequency of GFP-CsmA and GFP-ChsB in both anterograde and retrograde direction appeared lower in the kinA-deletion strain compared to wild type, although the velocities of the movements were comparable. Co-localization of GFP-ChsB and GFP-CsmA with mRFP1-KinArigor, a KinA mutant that binds to microtubules but does not move along them, was observed in the posterior of the hyphal tip regions. KinA co-immunoprecipitated with ChsB and CsmA. Co-localization and association of CsmA with KinA did not depend on the MMD. These findings indicate that ChsB and CsmA are transported along microtubules to the subapical region by KinA.
authors.affiliation: Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany; Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Takeshita
authors.affiliation: Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
authors.forename: Valentin
authors.initials: V
authors.lastname: Wernet
authors.affiliation: Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors.forename: Makusu
authors.initials: M
authors.lastname: Tsuizaki
authors.affiliation: Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Grün
authors.affiliation: Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors.forename: Hiro-Omi
authors.initials: HO
authors.lastname: Hoshi
authors.affiliation: Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Ohta
authors.affiliation: Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Fischer
authors.affiliation: Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Horiuchi
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics* / Q000254:growth & development; D002473:Cell Wall / Q000235:genetics / Q000378:metabolism; D002686:Chitin / Q000378:metabolism; D002687:Chitin Synthase / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D025301:Hyphae / Q000235:genetics* / Q000254:growth & development; D016547:Kinesins / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D021381:Protein Transport / Q000235:genetics
chemical_list: D005656:Fungal Proteins; C445330:KinA protein, Aspergillus nidulans; D002686:Chitin; D002687:Chitin Synthase; D016547:Kinesins