Prolyl 4-hydroxylase subunit alpha-3 (P4HA3)

Prolyl 4-hydroxylase subunit alpha-3 (P4HA3) is an enzyme subunit that serves as the catalytic component of prolyl 4-hydroxylase, which is essential for the post-translational modification of collagens and some collagen-like proteins[1][2]. This enzyme catalyzes the hydroxylation of proline residues within the -Xaa-Pro-Gly- motif of procollagen, creating 4-hydroxyproline, a modification critical for the stability and proper folding of collagen triple helices[2][7]. The enzyme complex typically consists of two alpha and two beta subunits, with P4HA3 providing catalytic specificity as one of several possible alpha isoforms[1][2]. P4HA3 is implicated in extracellular matrix organization, tissue structural integrity, and developmental processes requiring robust collagen synthesis. Upregulation of P4HA3 has been observed in multiple cancer types, notably gastric cancer, where it serves as a prognostic biomarker and may represent a therapeutic target, especially in association with tumor microenvironment remodeling and immune cell infiltration[5]. Inhibition of P4HA3—or the prolyl 4-hydroxylase activity more broadly—is of therapeutic interest in cancers and fibrotic diseases, but care must be taken due to its fundamental role in tissue homeostasis[5][3].

Other names

Prolyl 4-hydroxylase subunit alpha-3P4HA3UNQ711/PRO13744-PH alpha-3C-P4Halpha(III)Procollagen-proline,2-oxoglutarate-4-dioxygenase subunit alpha-3collagen prolyl 4-hydroxylase alpha(III)C-P4H alpha IIIprocollagen-proline, 2-oxoglutarate 4-dioxygenase (proline 4-hydroxylase)alpha polypeptide IIIprolyl 4-hydroxylase

Inhibition of prolyl 4-hydroxylase disrupts collagen maturation by preventing hydroxylation of proline residues, thereby affecting extracellular matrix stability and remodeling[1][5].