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

• Main Authors: Bruno Cosnier, Marta Kwapisz, Isabelle Hatin, Olivier Namy, Sylvie Hermann-Le Denmat, Antonin Morillon, Jean-Pierre Rousset, Céline Fabret
• Format: Article
• Language: English
• Published: Public Library of Science (PLoS) 2011-04-01
• Series: PLoS ONE
• Online Access: https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/21559332/?tool=EBI

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.