Regulation of glycolysis by casein kinase I (Rag8p) in Kluyveromyces lactis involves a DNA-binding protein, Sck1p, a homologue of Sgc1p of Saccharomyces cerevisiae.
The casein kinase I (Rag8p) of Kluyveromyces lactis has previously been shown to regulate the transcription of the low-affinity glucose transporter gene RAG1. To study this regulation, we have isolated multicopy suppressors of the rag8 mutation. One of them, SCK1 (suppressor of casein kinase), was characterised. The predicted product of the gene has a DNA-binding signature of the basic-helix-loop-helix type. It has an overall identity of 38% with Sgc1p (Tye7p) of Saccharomyces cerevisiae. The sck1 null mutant exhibited a Rag- phenotype (which indicates a reduced flux of glycolysis) that can be complemented by the SGC1 gene of S. cerevisiae. The level of transcription of several glycolytic genes, including RAG1, was reduced about twofold in glucose media in the sck1 null mutant. Moreover, in a rag8 mutant, the expression of SCK1 was strongly affected. Altogether, the results suggest that the regulation of glycolysis by casein kinase I involves, at least in part, Sck1p in K. lactis.
Lemaire
Marc
M
UMR 5122 CNRS/UCB/INSA, Microbiologie et Génétique, Université Claude Bernard, Bt Lwoff 43, Boulevard du 11 Novembre 1918, 69622, Villeurbanne Cédex, France.
Guyon
Anouchka
A
Betina
Svätopluk
S
Wésolowski-Louvel
Micheline
M
D000595:Amino Acid Sequence; D047388:Casein Kinases; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal / Q000235:genetics; D005816:Genetic Complementation Test; D005947:Glucose / Q000378:metabolism; D006019:Glycolysis; D007716:Kluyveromyces / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D010641:Phenotype; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D013489:Suppression, Genetic / Q000235:genetics; D015534:Trans-Activators; D014157:Transcription Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; C092673:TYE7 protein, S cerevisiae; D015534:Trans-Activators; D014157:Transcription Factors; D011494:Protein Kinases; D047388:Casein Kinases; D005947:Glucose