FIGURE 6: The pathways regulating PRMT5 in cancer. The activity, localization and protein-protein interaction are altered by indicated upstream components, posttranslational modification of PRMT5 or its adaptor protein, MEP50. PRMT5 interaction with adaptors serves to identify the substrates which will be methylated. PRMT5 activity is inhibited by the endogenous inhibitor, MTA, an MTAP substrate which is deleted in up to 30% of tumors.