Meu10 is required for spore wall maturation in Schizosaccharomyces pombe.
BACKGROUND
Many genes are meiosis and/or sporulation-specifically transcribed during this process. Isolation and analysis of these genes might help us to understand how meiosis and sporulation are regulated. For this purpose, we have isolated a large number of cDNA clones from Schizosaccharomyces pombe whose expression is up-regulated during meiosis.


RESULTS
We have isolated meu10+ gene, which encodes 416 amino acids and bears homology to SPS2 of Saccharomyces cerevisiae. A strain whose meu10+ gene has been deleted forms no viable spores. Thin-section electron micrographs showed that the meu10Delta strain has abnormally formed spore walls, and then they disrupt, allowing cytoplasmic material to escape. The Meu10-GFP fusion protein is localized to the spore periphery, thereafter returned to the cytoplasm after sporulation. Meu10-GFP localization to the spore wall was almost normal in the bgs2Delta or chs1Delta mutants that lack 1,3-beta-glucan or chitin, respectively. In contrast, 1,3-beta-glucan is abnormally localized in meu10Delta cells. Meu10 has an N-terminal domain with homology to the mammalian insulin receptor and a C-terminal domain with a transmembrane motif. Mutants whose N-terminal or C-terminal domain was truncated were severely defective for sporulation.


CONCLUSIONS
Meu10 is a spore wall component and plays a pivotal role in the formation of the mature spore wall structure.
Tougan
Takahiro
T
Department of Molecular Genetics, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita City, Osaka 565-0871, Japan.
Chiba
Yasuyoshi
Y
Kakihara
Yoshito
Y
Hirata
Aiko
A
Nojima
Hiroshi
H
D000595:Amino Acid Sequence; D005656:Fungal Proteins / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D012568:Schizosaccharomyces / Q000235:genetics / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics* / Q000502:physiology; D016415:Sequence Alignment; D017384:Sequence Deletion / Q000235:genetics; D013172:Spores, Fungal / Q000502:physiology* / Q000648:ultrastructure
D005656:Fungal Proteins; C460909:Meu10 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins