IMPAD1 (Inositol Monophosphatase Domain-Containing Protein 1), also known as GPAPP (Golgi-associated PAP phosphatase), is a phosphatase enzyme encoded by the IMPAD1 gene. It belongs to the inositol monophosphatase superfamily and is localized to the Golgi apparatus. IMPAD1 catalyzes the dephosphorylation of 3′-phosphoadenosine 5′-phosphate (PAP) to adenosine 5′-phosphate (AMP), a critical step in sulfation pathways, particularly in the biosynthesis of sulfated glycosaminoglycans (GAGs) like chondroitin sulfate. These GAGs are essential components of the extracellular matrix, influencing cell signaling, tissue development, and cartilage formation.
Research on IMPAD1 gained momentum after its association with skeletal dysplasia. Biallelic mutations in IMPAD1 were linked to chondrodysplasia with joint dislocations (CJDLD), a rare autosomal recessive disorder characterized by short stature, joint laxity, and skeletal abnormalities. Studies in Impad1-deficient mice revealed impaired chondrocyte differentiation and defective skeletal mineralization, underscoring its role in skeletal development.
IMPAD1 antibodies are vital tools for studying the protein’s expression, localization, and function in cellular and disease contexts. They are used in techniques like Western blotting, immunohistochemistry, and immunofluorescence to assess IMPAD1 levels in tissues or cultured cells, particularly in models of skeletal disorders or sulfation pathway dysregulation. These antibodies also aid in exploring IMPAD1’s interaction with Golgi-associated proteins and its regulatory mechanisms in GAG synthesis, offering insights into therapeutic strategies for related genetic or metabolic conditions.