NCIt definition : A tetrameric enzyme complex that catalyzes the post-translational formation of 4-hydroxyproline
in the amino acid sequence -Xaa-Pro-Gly-, which is found in collagens and other proteins.
The enzyme complex is comprised of two alpha chains and two beta chains. There are
3 separate genes that encode 3 distinct alpha proteins, prolyl 4-hydroxylase subunit
alpha-1, -2 and -3. The beta chain is protein disulfide-isomerase.;