Fig. 5: mTOR functions downstream of PLD and PA in HS-induced SREBP processing.

a Western blot analysis of the SREBP protein levels after HS treatment from 5-d-old WT mycelia. b Western blot analysis of the SREBP protein levels. The 5-d-old WT mycelia were pre-incubated with 0.3% 1-butanol (1-but), 0.3% 2-butanol (2-but), 100 nM rapamycin (Rapa), or 50 μg/100 mL PA for 30 min before being exposed to HS for 30 min. c, d Western blot analysis of the protein levels of SREBP after 30 min HS treatment from 5-d-old SiControl, pld- and mTOR-silenced strains. The pld- and mTOR-silenced strains were incubated with 50 μg/100 mL PA for 30 min before being exposed to HS. a–d P and N denote the full-length, precursor SREBP and the cleaved, active SREBP, respectively. The histogram in (a–d) shows the N-SREBP/β-Tubulin ratio which in the WT or SiControl strain under no HS treatments was arbitrarily set to 1. The values are the means ± SD (n = 3 independent experiments). Asterisks in (a) indicate significant differences from the no HS treatments (**P < 0.01 by Student’s t-test); ns: not significant. Different letters in (b–d) indicate significant differences between the lines (P < 0.05, according to Duncan’s multiple range test).