Procollagen-lysine,2-oxoglutarate 5-dioxygenase 3 is an enzyme that in humans is encoded by the PLOD3 gene. [5] [6] [7]
The protein encoded by this gene is a membrane-bound homodimeric enzyme that is localized to the cisternae of the rough endoplasmic reticulum. The enzyme (cofactors iron and ascorbate) catalyzes the hydroxylation of lysyl residues in collagen-like peptides. The resultant hydroxylysyl groups are attachment sites for carbohydrates in collagen and thus are critical for the stability of intermolecular crosslinks. Some patients with Ehlers-Danlos syndrome type VIB have deficiencies in lysyl hydroxylase activity. [7]
Lysyl hydroxylases are alpha-ketoglutarate-dependent hydroxylases enzymes that catalyze the hydroxylation of lysine to hydroxylysine. Lysyl hydroxylases require iron and vitamin C as cofactors for their oxidation activity. It takes place following collagen synthesis in the cisternae (lumen) of the rough endoplasmic reticulum (ER). There are three lysyl hydroxylases (LH1-3) encoded in the human genome, namely: PLOD1, PLOD2 and PLOD3. From PLOD2 two splice variant can be expressed, where LH2b differs from LH2a by incorporating the small exon 13A. LH1 and LH3 hydroxylate lysyl residues in the collagen triple helix, whereas LH2b hydroxylates lysyl residues in the telopeptides of collagen. In addition to its hydroxylation activity, LH3 has glycosylation activity that produces either monosaccharide (Gal) or disaccharide (Glc-Gal) attached to collagen hydroxylysines.
Collagen alpha-1 (XXVII) chain (COL27A1) is a protein that in humans is encoded by the COL27A1 gene.
Collagen alpha-1(V) chain is a protein that in humans is encoded by the COL5A1 gene.
Collagen alpha-2(V) chain is a protein that in humans is encoded by the COL5A2 gene.
Laminin subunit alpha-3 is a protein that in humans is encoded by the LAMA3 gene.
Collagen alpha-1(IX) chain is a protein that in humans is encoded by the COL9A1 gene.
Collagen alpha-2(VIII) chain is a protein that in humans is encoded by the COL8A2 gene. Mutations of the gene are linked to posterior polymorphous dystrophy type 2.
Prolyl 4-hydroxylase subunit alpha-1 is an enzyme that in humans is encoded by the P4HA1 gene.
Collagen alpha-1(VIII) chain is a protein that in humans is encoded by the COL8A1 gene.
Matrilin-2 is a matrilin protein that in humans is encoded by the MATN2 gene.
Prolyl 4-hydroxylase subunit alpha-2 is an enzyme that in humans is encoded by the P4HA2 gene.
Collagen alpha-3(V) chain is a protein that in humans is encoded by the COL5A3 gene.
Lysyl oxidase homolog 4 is an enzyme that in humans is encoded by the LOXL4 gene.
ADAMTS-like protein 1 is a protein that in humans is encoded by the ADAMTSL1 gene.
Zinc finger and BTB domain-containing protein 7B is a protein that in humans is encoded by the ZBTB7B gene. ZFP67 is an early growth response gene that encodes a zinc finger-containing transcription factor that binds to the promoter regions of type I collagen genes and has a role in development.[supplied by OMIM]
Tolloid-like protein 1 is a protein that in humans is encoded by the TLL1 gene.
Tolloid-like protein 2 is a protein that in humans is encoded by the TLL2 gene.
Integrin alpha-11 is a protein that, in humans, is encoded by the ITGA11 gene.
Lysyl oxidase homolog 3 is an enzyme that in humans is encoded by the LOXL3 gene.
Prolyl 4-hydroxylase, transmembrane is a protein that in humans is encoded by the P4HTM gene.