INSR and Insulin resistance: Interestingly, it was recently shown in mice that viral infection with murine cytomegalovirus (MCMV), influenza A (INFA) virus and lymphocytic choriomeningitis virus (LCMV) induce production of interferon gamma (IFN-γ) by natural killer (NK) cells, which downregulates insulin receptor transcription in skeletal muscle, causing insulin resistance without glucose elevation [18].