14-3-3 proteins are essential for RAS/MAPK cascade signaling during pseudohyphal development in S. cerevisiae.
14-3-3 proteins are highly conserved ubiquitous proteins whose explicit functions have remained elusive. Here, we show that the S. cerevisiae 14-3-3 homologs BMH1 and BMH2 are not essential for viability or mating MAPK cascade signaling, but they are essential for pseudohyphal-development MAPK cascade signaling and other processes. Activated alleles of RAS2 and CDC42 induce pseudohyphal development and FG(TyA)-lacZ signaling in Bmh+ strains but not in ste20 (p65PAK) or bmh1 bmh2 mutant strains. Moreover, Bmh1p and Bmh2p associate with Ste20p in vivo. Three alleles of BMH1 encode proteins defective for FG(TyA)-lacZ signaling and association with Ste20p, yet these alleles complement other 14-3-3 functions. Therefore, the 14-3-3 proteins are specifically required for RAS/MAPK cascade signaling during pseudohyphal development in S. cerevisiae.
Roberts
R L
RL
Whitehead Institute for Biomedical Research, Department of Biology, Massachusetts Institute of Technology, Cambridge 02142, USA.
Mösch
H U
HU
Fink
G R
GR
D048948:14-3-3 Proteins; D000222:Adaptation, Physiological; D000483:Alleles; D005075:Biological Evolution; D002470:Cell Survival / Q000502:physiology; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000378:metabolism; D006003:Glycogen / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D007763:Lac Operon / Q000235:genetics; D020930:MAP Kinase Kinase Kinases; D008969:Molecular Sequence Data; D016296:Mutagenesis / Q000502:physiology; D010641:Phenotype; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000235:genetics; D012098:Reproduction / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000166:cytology* / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000502:physiology*; D013045:Species Specificity; D018631:ras Proteins / Q000502:physiology*
D048948:14-3-3 Proteins; C075852:BMH1 protein, S cerevisiae; C097164:BMH2 protein, S cerevisiae; D005656:Fungal Proteins; D047908:Intracellular Signaling Peptides and Proteins; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D006003:Glycogen; D017346:Protein Serine-Threonine Kinases; D020930:MAP Kinase Kinase Kinases; C078754:STE20 protein, S cerevisiae; D019204:GTP-Binding Proteins; D018631:ras Proteins