Histone-lysine N-methyltransferase that acts as a regulator of cell proliferation, cell differentiation and inflammatory response. Regulates the inflammatory response by mediating mono- and dimethylation of 'Lys-4' of histone H3 (H3K4me1 and H3K4me2, respectively, leading to activate the transcription of proinflammatory cytokines IL6 and TNF-alpha (By similarity. Also involved in the regulation of stem cell quiescence by catalyzing the trimethylation of 'Lys-20' of histone H4 (H4K20me3, thereby promoting heterochromatin formation. Involved in proliferation, migration, paracrine and myogenic differentiation of bone marrow mesenchymal stem cells (BMSCs (By similarity.