Fig. 5.

SPAK depletion increases autophagy. (A) HeLa cells were treated with 30 nM siRNA for OSR1 and SPAK, individually or in combination (total 60 nM), as indicated. After 3 d, fresh medium was added for 4 h before harvest and protein immunoblotting. (B) Quantitation of the relative p62 change in A. *P < 0.05. NS, not significant. (C) HeLa cells were treated with 20 nM siRNA for SPAK and after 3 d, cells were starved for 4 h. Lysate proteins were immunoblotted. (D) Quantitation of the relative p62 change in C. *P < 0.05. (E) Quantitation of the relative change of LC3-II/LC3-I ratio in C. **P < 0.01. (F) A model of autophagy regulation by WNK1.