An actin point-mutation neighboring the 'hydrophobic plug' causes defects in the maintenance of cell polarity and septum organization in the fission yeast Schizosaccharomyces pombe.
The fission yeast cps8 mutation gives rise to abnormally enlarged and dispolarized cells, each of which contains several nuclei with aberrant multisepta. Molecular cloning and sequence analysis of the cps8 gene indicated that it encodes an actin with an amino acid substitution of aspartic acid for glycine at residue 273 in the hydrophobic loop that is located between actin subdomains 3 and 4. Fluorescence microscopy using phalloidin and anti-actin antibody revealed changes in the F-actin structure and distribution in the mutant cells. These results indicate that the hydrophobic loop plays an essential role for creating normal F-actin structure, only by which cell polarity and the late mitotic events can be maintained properly.
Ishiguro
J
J
Department of Biology, Faculty of Science, Konan University, Kobe, Japan.
Kobayashi
W
W
D000199:Actins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D016764:Cell Polarity / Q000235:genetics*; D003001:Cloning, Molecular; D003598:Cytoskeletal Proteins; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000737:chemistry; D008938:Mitosis; D008969:Molecular Sequence Data; D017354:Point Mutation; D011487:Protein Conformation; D015183:Restriction Mapping; D012568:Schizosaccharomyces / Q000235:genetics*; D029702:Schizosaccharomyces pombe Proteins
D000199:Actins; C101299:CPS8 protein, S pombe; D003598:Cytoskeletal Proteins; D005656:Fungal Proteins; D029702:Schizosaccharomyces pombe Proteins