Transcriptional profiling of extracellular amino acid sensing in Saccharomyces cerevisiae and the role of Stp1p and Stp2p.
S. cerevisiae responds to the presence of amino acids in the environment through the membrane-bound complex SPS, by altering transcription of several genes. Global transcription analysis shows that 46 genes are induced by L-citrulline. Under the given conditions there appears to be only one pathway for induction with L-citrulline, and this pathway is completely dependent on the SPS component, Ssy1p, and either of the transcription factors, Stp1p and Stp2p. Besides the effects on amino acid permease genes, an ssy1 and an stp1 stp2 mutant exhibit a number of other transcriptional phenotypes, such as increased expression of genes subject to nitrogen catabolite repression and genes involved in stress response. A group of genes involved in the upper part of the glycolysis, including those encoding hexose transporters Hxt4p, Hxt5p, Hxt6p, Hxt7p, hexokinase Hxk1p, glyceraldehyde 3-phosphate dehydrogenase Tdh1p and glucokinase (Glk1p), shows increased transcription levels in either or both of the mutants. Also, most of the structural genes involved in trehalose and glycogen synthesis and a few genes in the glyoxylate cycle and the pentose phosphate pathway are derepressed in the ssy1 and stp1 stp2 strains.
Eckert-Boulet
Nadine
N
Centre for Microbial Biotechnology, BioCentrum-DTU, Technical University of Denmark, DK-2800 Kgs Lyngby, Denmark.
Nielsen
Peter Stein
PS
Friis
Carsten
C
dos Santos
Margarida Moreira
MM
Nielsen
Jens
J
Kielland-Brandt
Morten C
MC
Regenberg
Birgitte
B
D002956:Citrulline / Q000096:biosynthesis* / Q000502:physiology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D020869:Gene Expression Profiling; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic / Q000502:physiology*
D004268:DNA-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; C120527:SSY1 protein, S cerevisiae; C074632:STP1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C421606:Stp2 protein, S cerevisiae; D014157:Transcription Factors; D002956:Citrulline