Figure 3

Effect of LI0758 on yeast MAPK signaling pathway. A. Heat shock activation of CWI (SLT2 phosphorylation) pathway. Yeast strains, transformed with control or LI0758-expressing plasmids, were heat-shocked at 39 °C for 30 min after 2 h induction. Immunoblotting showed total and activated SLT2 levels, with tubulin as a loading control. LI0758 expression was confirmed using an anti-Flag antibody. B. NaCl activation of HOG (HOG1 phosphorylation) pathway. Yeast strains, harboring control or LI0758-expressing plasmids, were treated with NaCl to induce a state of high osmolarity for 5 min after a 2 h induction period. Immunoblotting revealed both the total and activated forms of HOG1, with tubulin serving as a loading control. LI0758 expression was verified using an anti-Flag antibody. C. α-Factor activation of pheromone response (FUS3 phosphorylation) and filamentous growth (KSS1) pathways. Yeast strains, transformed with control or LI0758-expressing constructs, were exposed to 200 nM α-factor for 15 min following a 2 h induction. Immunoblotting demonstrated the total and activated states of FUS3 and KSS1, with tubulin as a loading control. The expression of LI0758 was confirmed by an anti-Flag antibody.