Hyaluronan synthase 1 (HAS1)

Hyaluronan synthase 1 is a membrane-bound glycosyltransferase enzyme responsible for synthesizing hyaluronan by catalyzing the alternating addition of N-acetylglucosamine (GlcNAc) and glucuronic acid (GlcUA) to the nascent polymer chain[1][2][3][5][6]. In humans, it is encoded by the HAS1 gene, one of three closely related hyaluronan synthases (HAS1, HAS2, HAS3), each with distinct regulatory and kinetic features[1][2]. HAS1 exhibits lower enzymatic activity compared to HAS2 and HAS3 but can be upregulated during inflammatory processes or by glucosamine, forming a structurally unique (“cloudy”) pericellular hyaluronan coat[2]. The enzyme’s product, hyaluronan, is critical for extracellular matrix structure, tissue hydration, cell migration, and wound healing. Dysregulation of HAS1 is associated with several cancer types, chronic inflammation, and other diseases due to aberrant extracellular matrix remodeling[2][1][5][6].

Other names

HAS1HA synthase 1

Drugs/agents like glucosamine upregulate HAS1 expression, leading to increased hyaluronan production[2]. Inflammation can also induce HAS1 expression[2].