The Saccharomyces cerevisiae RanGTP-binding protein msn5p is involved in different signal transduction pathways.
In eukaryotes, control of transcription by extracellular signals involves the translocation to the nucleus of at least one component of the signal transduction pathway. Transport through the nuclear envelope requires the activity of an import or export receptor that interacts with the small GTPase Ran. We have cloned the MSN5 gene of the yeast Saccharomyces cerevisiae that is postulated to encode one of these receptors. Msn5p belongs to a family of proteins with a conserved N-terminal sequence that acts as a RanGTP-binding domain. The results presented here provide genetic data supporting Msn5p involvement in several different signal transduction pathways. All of these pathways include changes in gene expression, and regulated nucleocytoplasmic redistribution of a component in response to external conditions has already been described in some of them. We have cloned MSN5 following two different strategies. Msn5p was constitutively localized in the nucleus. Phenotypic analysis of the msn5 mutant demonstrated that this protein participates in processes such as catabolite repression, calcium signaling, mating, and cell proliferation, as well as being involved in previously characterized phosphate utilization. Therefore, Msn5p could be a receptor for several proteins involved in different signaling pathways.
Alepuz
P M
PM
Departamento de Bioquímica y Biología Molecular (Universitat de Valencia) and Instituto de Agroquímica y Tecnología de Alimentos (CSIC), 46100 Burjassot (Valencia), Spain.
Matheos
D
D
Cunningham
K W
KW
Estruch
F
F
D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism*; D002467:Cell Nucleus / Q000502:physiology; D003001:Cloning, Molecular; D017931:DNA Primers; D005838:Genotype; D028884:Karyopherins; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009685:Nuclear Envelope / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins; D015398:Signal Transduction; D013489:Suppression, Genetic; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D020931:ran GTP-Binding Protein / Q000378:metabolism*
D002352:Carrier Proteins; D017931:DNA Primers; D028884:Karyopherins; C401306:MSN5 protein, S cerevisiae; D018160:Receptors, Cytoplasmic and Nuclear; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D020931:ran GTP-Binding Protein