High impact information on AGP1

• In the yck mutant lacking this kinase, Stp1 is not cleaved and AGP1 is not induced in response to amino acids [1].
• Saccharomyces cerevisiae cells possess a plasma membrane sensor able to detect the presence of extracellular amino acids and then to activate a signaling pathway leading to transcriptional induction of multiple genes, e.g., AGP1, encoding an amino acid permease [1].
• It was surprising that the same residues were not important for the role of Grr1 in nutrient-regulated transcription of HXT1 or AGP1 [2].
• We show here that SSY1 is required for transcriptional induction, in response to multiple amino acids, of the AGP1 gene encoding a low-affinity, broad-specificity amino acid permease [3].
• Amino acid signaling in Saccharomyces cerevisiae: a permease-like sensor of external amino acids and F-Box protein Grr1p are required for transcriptional induction of the AGP1 gene, which encodes a broad-specificity amino acid permease [3].

Biological context of AGP1

• The F-box protein Grr1p is involved in cell cycle regulation, glucose repression and transcriptional induction of the amino acid permease (AAP) gene AGP1 [4].

Associations of AGP1 with chemical compounds

• Ssy5 is significantly similar to serine proteases, its self-processing is a prerequisite for Stp1 cleavage, and its overexpression causes inducer-independent Stp1 cleavage and high-level AGP1 transcription [1].
• Consistent with a role for Ssy1p in the recognition of amino acids, a mutant form of the protein with a Thr to Ile substitution in the eighth predicted transmembrane domain is competent for the induction of AGP1 by leucine but not by other amino acids [5].
• Using strains with disruptions in the genes for multiple permeases, we demonstrated that Ycc5 (which we have renamed Agp1) is involved in the transport of asparagine and glutamine, performed a kinetic analysis of this activity, and showed that AGP1 expression is subject to nitrogen repression [6].
• Conversely, AGP1 is strongly induced by tryptophan in a mutant strain largely deficient in tryptophan uptake, but it remains unexpressed in a mutant that accumulates high levels of tryptophan endogenously [3].
• The Saccharomyces cerevisiae YCC5 (YCL025c) gene encodes an amino acid permease, Agp1, which transports asparagine and glutamine [6].

Other interactions of AGP1

• In a screen for other mutants defective in the Ssy1p pathway, we confirmed that PTR3 and SSY5 encode additional factors essential for AGP1 expression in response to multiple amino acids [5].
• Nitrogen-source control of AGP1 induction is mediated by the GATA factor Gln3, likely acting through adjacent 5'-GATA-3' sequences, to amplify the positive effect of UAS(AA) [7].
• In response to external amino acids, the permease-like sensor Ssy1 of Saccharomyces cerevisiae activates a pathway leading to transcriptional induction of several permease genes including AGP1 and PTR2 [8].

References