Fig. 3.

Radiation-induced early activation of Jak3/STAT3 and Erk is suppressed by SOCS1, and the inhibition of Jak3/STAT3 and Erk in shSOCS1 cells leads to G1 arrest restoration. Analysis of Jak/STAT and MAPK activation kinetics induced by γ-IR. HCT116/p53 wt cells stably transfected with HA and HA-SOCS1 were exposed to γ-IR at 5 Gy and harvested at indicated time points. Cell lysates were prepared to analyze Jak/STAT and MAPK activation status by immunblotting (A). sh and shSOCS1-transfected cells were analyzed for Jak/STAT and MAPK activation status and cell cycle changes upon irradiation with or without pre-treatment with inhibitors of Jak (AG490) or Erk (PD). Effects of AG490 and PD on on Jak/STAT and Erk were examined (B, C: Supplementary Fig. 6B).