Investigation of the relationship between sphingolipid and insulin signaling pathways

Ceramide functioning in sphingolipid metabolism is known to inhibit Akt/ protein kinase B (PKB) which is one of the core proteins of insulin signaling pathway. However, the mechanism of crosstalk between sphingolipid signaling pathway and insulin signaling pathway has not been determined completely. In this study, we have investigated the proteins which play important roles in the association of sphingolipid and insulin signaling pathways. Our results show that in Ypk1 deletion mutant, the glucose uptake is decreased whereas the amounts of complex sphingolipids are increased. Glucose uptake is relatively higher in Ypk2 and Pkh1 deletion mutants compared to Ypk1 deletion mutant and glucose uptake is highest in wild type yeast strain. The amounts of complex sphingolipids are found to decrease in Ypk2 and Pkh1 deletion mutants of yeast.