Mth1 receives the signal given by the glucose sensors Snf3 and Rgt2 in Saccharomyces cerevisiae.
We have determined that the mutant genes DGT1-1 and BPC1-1, which impair glucose transport and catabolite repression in Saccharomyces cerevisiae, are allelic forms of MTH1. Deletion of MTH1 had only slight effects on the expression of HXT1 or SNF3, but increased expression of HXT2 in the absence of glucose. A two-hybrid screen revealed that the Mth1 protein interacts with the cytoplasmic tails of the glucose sensors Snf3 and Rgt2. This interaction was affected by mutations in Mth1 and by the concentration of glucose in the medium. A double mutant, snf3 rgt2, recovered sensitivity to glucose when MTH1 was deleted, thus showing that glucose signalling may occur independently of Snf3 and Rgt2. A model for the possible mode of action of Snf3 and Rgt2 is presented.
Lafuente
M J
MJ
Instituto de Investigaciones Biom¿edicas 'Alberto Sols', CSIC-UAM, Arturo Duperier 4, 28029 Madrid, Spain.
Gancedo
C
C
Jauniaux
J C
JC
Gancedo
J M
JM
D048868:Adaptor Proteins, Signal Transducing; D000483:Alleles; D001483:Base Sequence; D001692:Biological Transport; D017931:DNA Primers; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D009004:Monosaccharide Transport Proteins / Q000378:metabolism*; D010641:Phenotype; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D015398:Signal Transduction; D020798:Two-Hybrid System Techniques
D048868:Adaptor Proteins, Signal Transducing; D017931:DNA Primers; D005656:Fungal Proteins; C118806:MTH1 protein, S cerevisiae; D008565:Membrane Proteins; D009004:Monosaccharide Transport Proteins; C112512:RGT2 protein, S cerevisiae; C104463:SNF3 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D005947:Glucose