Type II interferon produced by immune cells such as T-cells and NK cells that plays crucial roles in antimicrobial , antiviral , and antitumor responses by activating effector immune cells and enhancing antigen presentation. Primarily signals through the JAK-STAT pathway after interaction with its receptor IFNGR1 to affect gene regulation. Upon IFNG binding , IFNGR1 intracellular domain opens out to allow association of downstream signaling components JAK2 , JAK1 and STAT1 , leading to STAT1 activation , nuclear translocation and transcription of IFNG-regulated genes. Many of the induced genes are transcription factors such as IRF1 that are able to further drive regulation of a next wave of transcription. Plays a role in class I antigen presentation pathway by inducing a replacement of catalytic proteasome subunits with immunoproteasome subunits. In turn , increases the quantity , quality , and repertoire of peptides for class I MHC loading. Increases the efficiency of peptide generation also by inducing the expressIFNG;IFG;IFI;Type II Interferon