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A viable hypomorphic allele of the essential IMP3 gene reveals novel protein functions in Saccharomyces cerevisiae.

ABSTRACT: In Saccharomyces cerevisiae, the essential IMP3 gene encodes a component of the SSU processome, a large ribonucleoprotein complex required for processing of small ribosomal subunit RNA precursors. Mutation of the IMP3 termination codon to a sense codon resulted in a viable mutant allele producing a C-terminal elongated form of the Imp3 protein. A strain expressing the mutant allele displayed ribosome biogenesis defects equivalent to IMP3 depletion. This hypomorphic allele represented a unique opportunity to investigate and better understand the Imp3p functions. We demonstrated that the +1 frameshifting was increased in the mutant strain. Further characterizations revealed involvement of the Imp3 protein in DNA repair and telomere length control, pointing to a functional relationship between both pathways and ribosome biogenesis.

SUBMITTER: Cosnier B

PROVIDER: S-EPMC3084874 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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A viable hypomorphic allele of the essential IMP3 gene reveals novel protein functions in Saccharomyces cerevisiae.

Cosnier Bruno B Kwapisz Marta M Hatin Isabelle I Namy Olivier O Hermann-Le Denmat Sylvie S Morillon Antonin A Rousset Jean-Pierre JP Fabret Céline C

PloS one 20110429 4

In Saccharomyces cerevisiae, the essential IMP3 gene encodes a component of the SSU processome, a large ribonucleoprotein complex required for processing of small ribosomal subunit RNA precursors. Mutation of the IMP3 termination codon to a sense codon resulted in a viable mutant allele producing a C-terminal elongated form of the Imp3 protein. A strain expressing the mutant allele displayed ribosome biogenesis defects equivalent to IMP3 depletion. This hypomorphic allele represented a unique op ...[more]

PMID: 21559332

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