title: A large nonconserved region of the tethering protein Leashin is involved in regulating the position, movement, and function of Woronin bodies in Aspergillus oryzae.
abstract: The Woronin body is a Pezizomycotina-specific organelle that is typically tethered to the septum, but upon hyphal wounding, it plugs the septal pore to prevent excessive cytoplasmic loss. Leashin (LAH) is a large Woronin body tethering protein that contains highly conserved N- and C-terminal regions and a long (∼2,500-amino-acid) nonconserved middle region. As the involvement of the nonconserved region in Woronin body function has not been investigated, here, we functionally characterized individual regions of the LAH protein of Aspergillus oryzae (AoLAH). In an Aolah disruptant, no Woronin bodies were tethered to the septum, and hyphae had a reduced ability to prevent excessive cytoplasmic loss upon hyphal wounding. Localization analysis revealed that the N-terminal region of AoLAH associated with Woronin bodies dependently on AoWSC, which is homologous to Neurospora crassa WSC (Woronin body sorting complex), and that the C-terminal region was localized to the septum. Elastic movement of Woronin bodies was observed when visualized with an AoLAH N-terminal-region-enhanced green fluorescent protein (EGFP) fusion protein. An N- and C-terminal fusion construct lacking the nonconserved middle region of AoLAH was sufficient for the tethering of Woronin bodies to the septum. However, Woronin bodies were located closer to the septum and exhibited impaired elastic movement. Moreover, expression of middle-region-deleted AoLAH in the Aolah disruptant did not restore the ability to prevent excessive cytoplasmic loss. These findings indicate that the nonconserved middle region of AoLAH has functional importance for regulating the position, movement, and function of Woronin bodies.
authors.affiliation: Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors.forename: Pei
authors.initials: P
authors.lastname: Han
authors.affiliation: Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors.forename: Feng Jie
authors.initials: FJ
authors.lastname: Jin
authors.affiliation: Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan amarujun@mail.ecc.u-tokyo.ac.jp.
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Maruyama
authors.affiliation: Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kitamoto
mesh_terms: D001236:Aspergillus oryzae / Q000378:metabolism* / Q000648:ultrastructure; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D025301:Hyphae / Q000378:metabolism* / Q000648:ultrastructure; D011485:Protein Binding; D017434:Protein Structure, Tertiary
chemical_list: D005656:Fungal Proteins