User:Amir Mitchell/Gal4
From Proteopedia
| Line 4: | Line 4: | ||
genes of the galactose metabolism pathay [http://www.genome.jp/dbget-bin/www_bget?pathway+sce00052]. The galactose regulon | genes of the galactose metabolism pathay [http://www.genome.jp/dbget-bin/www_bget?pathway+sce00052]. The galactose regulon | ||
| - | == | + | ==Regulation of the Pathway== |
| - | == | + | ==Mutation in Gal4== |
| + | gal81c - constitutive [http://books.google.com/books?id=NUdsb6HDJpsC&pg=PA334&lpg=PA334&dq=gal80+gal4+regulation&source=web&ots=AERd1BIGOm&sig=19deQdSn4MbLdDK3SdG-hyc34V4&hl=en&sa=X&oi=book_result&resnum=8&ct=result#PPA334,M1] | ||
Revision as of 14:39, 28 September 2008
Galactose Metabolism Pathway
Gal4 is a yeast transcription factor. This positive regulator induces the metabolic pathway for the conversion of β-d-galactose to the glucose-1-phosphate (the Leloir pathway). The set of structural and regulatory genes of the galactose pathway has served as a model system for the study of transcription regulation in eukaryots.
genes of the galactose metabolism pathay [1]. The galactose regulon
Regulation of the Pathway
Mutation in Gal4
gal81c - constitutive [2]
genes of the galactose metabolism pathay [3]. The galactose regulon
The key for survival of an organism is to sense changes in the environment both strong and subtle, and to respond to these cues. These alterations or fluctuations are sensed at the cell periphery and communicated to the nucleus through signaling pathways leading to adaptive gene expression. The galactose regulon, a set of structural and regulatory genes that enable Saccharomyces cerevisiae cells to utilize galactose as a carbon source, is a paradigm of transcription regulation in eukaryotic systems. The conversion of β-d-galactose to the metabolically required glucose-1-phosphate is carried out by a set of four enzymes that constitutes the Leloir pathway (reviewed in Holden et al., 2003 H.M. Holden, I. Rayment and J.B. Thoden, Structure and function of enzymes of the Leloir pathway for galactose metabolism, J. Biol. Chem. 278 (2003) (45), pp. 43885–43888. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (60)Holden et al., 2003). The four enzymes of this pathway are (1) Galactose mutarotase, which performs epimerization of β-d-galactose to α-d-galactose (2) Galactokinase, which catalyzes an ATP-dependent phosphorylation of α-d-galactose to galactose-1-phosphate. (3) Galactose-1-phosphate uridylyltransferase, which catalyzes the transfer of a UMP group from UDP-glucose to galactose-1-phosphate to give UDP-galactose. (4) UDP-galactose-4-epimerase, which catalyses the conversion of UDP-galactose to UDP-glucose. In S. cerevisiae galactokinase and galactose-1-phosphate uridylyltransferase are referred to as GAL1 and GAL7, respectively. The first and the last enzyme of the pathway are contained within a single polypeptide chain known as Gal10. In Gal10 the epimerase and mutarotase domains are completely separate structural units connected by a Type II turn (Thoden and Holden, 2005). The mutarotase domain of Gal10 is dispensable for growth of S. cerevisiae on galactose (Seiboth et al., 2002).
| |||||||||
| 1d66, resolution 2.70Å () | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Ligands: | |||||||||
| |||||||||
| |||||||||
| Resources: | FirstGlance, OCA, RCSB, PDBsum | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
