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A mutant defective in sexual development produces aseptate ascogonia.

ABSTRACT: The transition from the vegetative to the sexual cycle in filamentous ascomycetes is initiated with the formation of ascogonia. Here, we describe a novel type of sterile mutant from Sordaria macrospora with a defect in ascogonial septum formation. This mutant, named pro22, produces only small, defective protoperithecia and carries a point mutation in a gene encoding a protein that is highly conserved throughout eukaryotes. Sequence analyses revealed three putative transmembrane domains and a C-terminal domain of unknown function. Live-cell imaging showed that PRO22 is predominantly localized in the dynamic tubular and vesicular vacuolar network of the peripheral colony region close to growing hyphal tips and in ascogonia; it is absent from the large spherical vacuoles in the vegetative hyphae of the subperipheral region of the colony. This points to a specific role of PRO22 in the tubular and vesicular vacuolar network, and the loss of intercalary septation in ascogonia suggests that PRO22 functions during the initiation of sexual development.

SUBMITTER: Bloemendal S

PROVIDER: S-EPMC3008273 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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A mutant defective in sexual development produces aseptate ascogonia.

Bloemendal Sandra S Lord Kathryn M KM Rech Christine C Hoff Birgit B Engh Ines I Read Nick D ND Kück Ulrich U

Eukaryotic cell 20101015 12

The transition from the vegetative to the sexual cycle in filamentous ascomycetes is initiated with the formation of ascogonia. Here, we describe a novel type of sterile mutant from Sordaria macrospora with a defect in ascogonial septum formation. This mutant, named pro22, produces only small, defective protoperithecia and carries a point mutation in a gene encoding a protein that is highly conserved throughout eukaryotes. Sequence analyses revealed three putative transmembrane domains and a C-t ...[more]

PMID: 20952581

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A mutant defective in sexual development produces aseptate ascogonia.

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A mutant defective in sexual development produces aseptate ascogonia.

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