Role for the Ran binding protein, Mog1p, in Saccharomyces cerevisiae SLN1-SKN7 signal transduction.
Yeast Sln1p is an osmotic stress sensor with histidine kinase activity. Modulation of Sln1 kinase activity in response to changes in the osmotic environment regulates the activity of the osmotic response mitogen-activated protein kinase pathway and the activity of the Skn7p transcription factor, both important for adaptation to changing osmotic stress conditions. Many aspects of Sln1 function, such as how kinase activity is regulated to allow a rapid response to the continually changing osmotic environment, are not understood. To gain insight into Sln1p function, we conducted a two-hybrid screen to identify interactors. Mog1p, a protein that interacts with the yeast Ran1 homolog, Gsp1p, was identified in this screen. The interaction with Mog1p was characterized in vitro, and its importance was assessed in vivo. mog1 mutants exhibit defects in SLN1-SKN7 signal transduction and mislocalization of the Skn7p transcription factor. The requirement for Mog1p in normal localization of Skn7p to the nucleus does not fully account for the mog1-related defects in SLN1-SKN7 signal transduction, raising the possibility that Mog1p may play a role in Skn7 binding and activation of osmotic response genes.
Lu
Jade Mei-Yeh
JM
Department of Biological Sciences, University of Iowa, 202 BBE, Iowa City, IA 52242, USA.
Deschenes
Robert J
RJ
Fassler
Jan S
JS
D021581:Active Transport, Cell Nucleus; D015152:Blotting, Northern; D015153:Blotting, Western; D002467:Cell Nucleus / Q000378:metabolism; D003470:Culture Media / Q000494:pharmacology; D004247:DNA / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry; D015966:Gene Expression Regulation, Fungal; D049452:Green Fluorescent Proteins / Q000737:chemistry / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D008856:Microscopy, Fluorescence; D009154:Mutation; D009687:Nuclear Proteins / Q000378:metabolism / Q000502:physiology*; D009995:Osmosis; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011494:Protein Kinases / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D015398:Signal Transduction; D013696:Temperature; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques; D020931:ran GTP-Binding Protein / Q000378:metabolism / Q000502:physiology*
D003470:Culture Media; D005656:Fungal Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D049452:Green Fluorescent Proteins; D004247:DNA; D011494:Protein Kinases; C083749:SLN1 protein, S cerevisiae; C410219:MOG1 protein, S cerevisiase; D020931:ran GTP-Binding Protein