Hyaluronan synthase 1, HAS1, glycosaminoglycan hyaluronan, hyaluronic acid, HA, cell proliferation, differentiation, angiogenesis, tumor development, cellular processes, membrane, transmembrane helix, transmembrane, glycosyltransferase, transferase, phosphorylation, cell adhesion, hyaloronan biosynthetic process, PDGF, metabolism, fibroblast, and cell migration