Jak2 kinase activity is essential for IFN-γ complex internalization and degradation. (A-B) Unstimulated MEFs from Jak2^+/+, Jak2^FF/FF, Jak2^−/−, and Jak1^−/− mice were analyzed for IFNGR1 and IFNGR2 surface expression by flow cytometry. One representative experiment of 3 independent experiments run in triplicates is shown. The standard deviation is indicated for each data point. (C-D) MEFs from Jak2^+/+, Jak2^FF/FF, Jak2^−/−, and Jak1^−/− mice were stimulated with IFN-γ for the indicated time points or left untreated. IFNGR1 and IFNGR2 surface expression was measured via fluorescence-activated cell sorter analysis. One representative experiment of 3 independent experiments run in triplicate is shown. The standard deviation is indicated for each data point.