Detailed Western Blot Procedure

Western blot was performed as reported in Fullone et al. 2022 [5 (link)]. The following primary antibodies were used at a dilution of 1:1000 in the blocking solution: rabbit anti-ERK (Santa Cruz Biotechnology, Dallas, TX, USA, sc-153), mouse anti-p-ERK (Cell Signaling Technology, Danvers, MA, USA, 9106S), monoclonal anti polyhistidine peroxidase (Sigma-Aldrich, MERCK, Darmstadt, Germany A7058), rabbit anti-MRAP2 polyclonal antibody (Invitrogen-Thermo Fisher Scientific, Waltham, MA, USA, PA5-113283), mouse anti-PKR2 polyclonal antibody (Santa Cruz Biotechnology, Dallas, TX, USA, sc-365696), mouse anti-STAT3, and rabbit anti-pSTAT3 (Tyr705) (1:1000, Invitrogen, Thermo Fisher Scientific, Waltham, MA, USA). After extensive washing with T-TBS, membranes were incubated with the appropriate IgG HRP-linked secondary antibody for 1 h at room temperature. The immunoreactive signals were visualized using an enhanced chemiluminescence system.