Ultrastructure of cell wall of the cps8 actin mutant cell in Schizosaccharomyces pombe.
A Schizosaccharomyces pombe cps8 mutant, of which the gene encodes a mutant actin with an amino acid substitution of Asp for Gly(273) [J. Ishiguro and W. Kobayashi (1996) FEBS Lett. 392, 237-241], was used to determine the role of the actin cytoskeleton in cell wall formation. In the cps8 mutant cells, atomic force microscopic and scanning electron microscopic images showed abnormal depolarized and branched morphology. Fibrous material covered a part of the surface of growing cps8 cells. Transmission electron microscopic images showed variable thickness of the cell wall due to multilayering of cell wall materials, and aberrant multisepta due to diagonal growth of the primary septum, whereas the normal primary septum grows at a right angle from the cortex. This abnormal septum formation may induce abnormality of the cell with multinuclei and/or multisepta, caused by non-separation of daughter cells. These results indicate that actin plays an important role in cell wall and septum formation.
Ishijima
S A
SA
Department of Chemical and Biological Sciences, Faculty of Science, Japan Women's University, 2-8-1, Mejirodai, Bunkyo-ku, Tokyo, Japan.
Konomi
M
M
Takagi
T
T
Sato
M
M
Ishiguro
J
J
Osumi
M
M
D000199:Actins / Q000235:genetics*; D003598:Cytoskeletal Proteins; D005656:Fungal Proteins / Q000235:genetics*; D018625:Microscopy, Atomic Force; D008854:Microscopy, Electron; D017354:Point Mutation; D012568:Schizosaccharomyces / Q000737:chemistry / Q000235:genetics / Q000648:ultrastructure*; D029702:Schizosaccharomyces pombe Proteins
D000199:Actins; C101299:CPS8 protein, S pombe; D003598:Cytoskeletal Proteins; D005656:Fungal Proteins; D029702:Schizosaccharomyces pombe Proteins