IFNGR1 and melanoma: To address this, we re-expressed Ifngr1 in scrambled control and IFNγR1KO cells to comparable levels (IFNγR1R) (Fig. 3d), using lentiviruses encoding mouse Ifngr1. Compellingly, IFNγR1R greatly reduced p-JAK1/2 in IFNγR1KO cells and largely rescued the overly increased p-JAK1/2 (Fig. 3e), directly linking lack of IFN-γ signaling to aberrant JAK1/2 activation in melanoma.