Trehalose pathway regulates filamentation response in Saccharomyces cerevisiae

In Saccharomyces cerevisae , the diploid cells undergo either pseudohyphal differentiation or sporulation in response to carbon and nitrogen source depletion. Distinct pathways are known to regulate the processes of filamentation and sporulation in response to nutritional stress. Here, we report the novel finding that the trehalose pathway which is essential for sporulation, is involved in pseudohyphae formation both via GPR1 as well as RAS2 mediated signaling. Our observations indicate that GPR1 is epistatic over TPS1 in signaling for filamentation. Further, we have demonstrated that the pseudohyphal defect of the ras2 mutant is overcome upon disruption of TPS2 . Thus, our results indicate that TPS1 and TPS2 may be involved in cell fate decision between meiosis and filamentation response under nutrient depleting conditions. Further, monitoring pseudohyphae formation under limiting glucose condition unravelled the possibility that TPS1 and TPS2 exert opposing effects to trigger filamentation response.