Title: | The yeast nuclear import receptor is required for mitosis |
Author(s): | Loeb JD; Schlenstedt G; Pellman D; Kornitzer D; Silver PA; Fink GR; |
Address: | "Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge 02142, USA" |
ISSN/ISBN: | 0027-8424 (Print) 1091-6490 (Electronic) 0027-8424 (Linking) |
Abstract: | "The nuclear import system is highly conserved among eukaryotes. Here we report the effects of a conditional mutation in SRP1, which encodes a Saccharomyces cerevisiae homolog of the vertebrate nuclear import receptor importin. Importin was isolated as a factor required for the initial targeting step of a nuclear import substrate to the nuclear envelope in a mammalian in vitro assay. We show that yeast Srp1 is similarly required for protein import. In addition, Srp1 is also required for the execution of mitosis: we demonstrate that cells containing a conditional mutation of SRP1 arrest with a G2/M phenotype in a manner analogous to classic cdc mutants. This defect may be due to the failure of the mutant to degrade the mitotic cyclin Clb2 and other proteins required for mitosis. The requirement of a nuclear import receptor for cell cycle-regulated proteolysis implies that import of cell cycle regulators into the nucleus is critical for cell cycle progression" |
Keywords: | "Animals Base Sequence Cell Nucleus/*physiology DNA Primers Genes, Fungal Genes, Lethal Genotype Karyopherins Mating Factor *Mitosis Molecular Sequence Data Mutagenesis Nuclear Proteins/genetics/*metabolism Peptides/metabolism Pheromones/metabolism Polymer;" |
Notes: | "MedlineLoeb, J D Schlenstedt, G Pellman, D Kornitzer, D Silver, P A Fink, G R eng GM-36373/GM/NIGMS NIH HHS/ GM-40266/GM/NIGMS NIH HHS/ Research Support, U.S. Gov't, P.H.S. 1995/08/15 Proc Natl Acad Sci U S A. 1995 Aug 15; 92(17):7647-51. doi: 10.1073/pnas.92.17.7647" |