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Dictyostelium amoebae lacking an F-box protein form spores rather than stalk in chimeras with wild type.

ABSTRACT: Using a selection for Dictyostelium mutants that preferentially form spores, we have recovered a mutant called CheaterA. In chimeras with isogenic wild-type cells, the CheaterA mutant preferentially forms viable spores rather than inviable stalk cells. The mutant causes wild-type cells that have begun to express spore-specific genes to accumulate in the prestalk compartment of the developing organism. In the wild-type cells, the chtA transcript is absent in growing cells and appears early in development. No transcript was detected in the mutant by Northern blot. The chtA gene codes for a protein with an F-box and WD40 domains. This class of protein usually forms part of an Skp1, cullin, F-box (SCF) complex that targets specific protein substrates for ubiquitination and degradation.

SUBMITTER: Ennis HL

PROVIDER: S-EPMC16232 | biostudies-literature | 2000 Mar

REPOSITORIES: biostudies-literature

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Dictyostelium amoebae lacking an F-box protein form spores rather than stalk in chimeras with wild type.

Ennis H L HL Dao D N DN Pukatzki S U SU Kessin R H RH

Proceedings of the National Academy of Sciences of the United States of America 20000301 7

Using a selection for Dictyostelium mutants that preferentially form spores, we have recovered a mutant called CheaterA. In chimeras with isogenic wild-type cells, the CheaterA mutant preferentially forms viable spores rather than inviable stalk cells. The mutant causes wild-type cells that have begun to express spore-specific genes to accumulate in the prestalk compartment of the developing organism. In the wild-type cells, the chtA transcript is absent in growing cells and appears early in dev ...[more]

PMID: 10725352

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