Identification and characterization of a novel yeast gene: the YGP1 gene product is a highly glycosylated secreted protein that is synthesized in response to nutrient limitation.

Abstract

Nutrient starvation in the yeast Saccharomyces cerevisiae leads to a number of physiological changes that accompany entry into stationary phase. The expression of genes whose products play a role in stress adaptation is regulated in a manner that allows the cell to sense and respond to changing environmental conditions. We have identified a novel yeast gene, YGP1, that displays homology to the sporulation-specific SPS100 gene. The expression of YGP1 is regulated by nutrient availability. The gene is expressed at a basal level during "respiro-fermentative" (logarithmic) growth. When the glucose concentration in the medium falls below 1%, the YGP1 gene is derepressed and the gene product, gp37, is synthesized at levels up to 50-fold above the basal level. The glucose-sensing mechanism is independent of the SNFJ pathway and does not operate when cells are directly shifted to a low glucose concentration. The expression of YGPJ also responds to the depletion of nitrogen and phosphate, indicating a general response to nutrient deprivation. These results suggest that the YGP1 gene product may be involved in cellular adaptations prior to stationary phase and may be a useful marker protein for monitoring early events associated with the stress response.

Genome-wide Analysis of the Response to Cell Wall Mutations in the Yeast Saccharomyces cerevisiae

“…Interestingly enough, we also identify several genes, which code for proteins that have a structural role in the architecture of the cell wall. This is the case for PIR3, PST1, SED1, YGP1, and SPI1, also known to be induced under poor nutritional conditions (54,(73)(74)(75). Another very important subset of up-regulated genes are those encoding putative ␤-glucanosyl/glucosyltransferase activity (BGL2, CRH1, and SCW10 (76,77)) and ␤-1,3-glucanase (EXG1 (78)).…”

Isc1p Plays a Key Role in Hydrogen Peroxide Resistance and Chronological Lifespan through Modulation of Iron Levels and Apoptosis

“…Disruption of the ISC1 gene also increased the expression of PDR5, which encodes an ABC drug efflux pump, which is important for cellular detoxification (Mamnun et al, 2004), and PUP2, which encodes a subunit of the 20S proteasome, which is involved in the degradation of oxidized proteins (Inai and Nishikimi, 2002;Shringarpure et al, 2003). Several genes up-regulated in the isc1⌬ mutant cells that were associated with cell rescue and defense encode cell wall proteins (Table 2), namely TIR2-4, which are induced under anaerobic conditions (Abramova et al, 2001), and YGP1, which is induced by nutrient starvation (Destruelle et al, 1994), as well as proteins involved in cell wall stress signal transduction (MTL1) or cell wall biogenesis (GSC2 and ROM1; see Supplementary Table S1). The up-regulation of YGP1 and PDR5 in cells lacking Isc1p was also observed in another yeast strain (Cowart et al, 2006).…”

Purification and biochemical characterization of the ATH1 gene product, vacuolar acid trehalase, from Saccharomyces cerevisiae

“…1). However, they analyzed the 37 kDa protein (now known to represent gp37 [17]) as ATH instead of the 85 kDa band. These results suggest that the 85 kDa deglycosylated species correspond to ATH.…”

“…Even though they achieved an over 7000-fold purification of ATH activity, it appears that they copurified an additional protein. This highly glycosylated protein, gp37 [17], was most likely the protein characterized in an earlier study [9].…”