Fig. 4.

STAT6 is degraded by AA starvation-induced autophagy. A–B Jurkat, MEF and PM1 cells were exposed to AA starvation media for the indicated time and then processed for immunoblot analysis. Antibodies against STAT6, LC3, actin, or tubulin were used.  C Jurkat cells were cultured for 6 h in starvation media and then supplemented with AA for the indicate times. Protein extracts were subjected to immunoblot analysis with antibodies to STAT6, tubulin, or LC3. D The blot from (A) was re-probed with antibodies to STAT1, STAT2, STAT3, STAT4 or PARP-1. E CAPNS1^−/− cells expressing human CAPNS1 or empty vector were subjected to AA starvation for the indicated times. Protein extracts were then subjected to immunoblot analysis with antibodies to STAT6, CAPNS1, LC3 or actin. F Putative CMA-targetable motifs on STAT6. G Jurkat cells subjected to AA starvation for 6 h were concomitantly treated with CMA inducers or inhibitors or calpastatin. Levels of STAT6 and autophagy status were assessed by immunoblot analysis of protein extracts with antibodies to STAT6, LC3 or actin