GO:0019797 procollagen-proline 3-dioxygenase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0019797 defines the enzymatic activity that adds a hydroxyl group to the third carbon of proline residues in procollagen, producing trans-3-hydroxy-L-proline.
• This 2-oxoglutarate-dependent dioxygenase requires Fe(II), 2-oxoglutarate, O2, and ascorbate for catalysis.
• Prolyl 3-hydroxylase (P3H) enzymes, including P3H1, P3H2, and P3H3, catalyze this modification, primarily on proline 986 of the collagen alpha-1(I) chain.
• 3-Hydroxylation is a minor but critical post-translational modification that influences collagen triple-helix stability and fibril assembly.
• Dysregulation of prolyl 3-hydroxylation is linked to connective tissue disorders, fibrosis, and cancer progression [1,7].
• CRISPR-based knockout, knock-in, and overexpression models enable precise functional studies of P3H enzymes and their substrates [1,8].
Description
Procollagen-proline 3-dioxygenase activity (GO:0019797) is a molecular function that catalyzes the stereospecific hydroxylation of proline residues in procollagen to form trans-3-hydroxy-L-proline. This modification, although less abundant than 4-hydroxylation, plays a critical role in collagen structure and function. The enzyme belongs to the 2-oxoglutarate-dependent dioxygenase family, which requires ferrous iron, 2-oxoglutarate, molecular oxygen, and ascorbate as cofactors. Researchers study this activity to understand collagen biosynthesis, extracellular matrix remodeling, and related pathologies such as fibrosis and connective tissue diseases [1,7]. The reaction consumes 2-oxoglutarate and O2 while producing succinate, CO2, and the hydroxylated proline. Because collagen is the most abundant protein in mammals, even minor modifications like 3-hydroxylation can have significant physiological consequences.
procollagen-proline 3-dioxygenase activity At A Glance
| GO ID | GO:0019797 |
|---|---|
| GO term | procollagen-proline 3-dioxygenase activity |
| Ontology | molecular_function |
| Synonym | prolyl 3-hydroxylase activity; procollagen-proline,2-oxoglutarate 3-dioxygenase activity; proline,2-oxoglutarate 3-dioxygenase activity |
| Major function | Catalyzes the 3-hydroxylation of proline residues in procollagen, a post-translational modification essential for collagen stability and assembly. |
| Cofactors | Fe(II), 2-oxoglutarate, O2, ascorbate |
| Reaction | procollagen L-proline + 2-oxoglutarate + O2 = procollagen trans-3-hydroxy-L-proline + succinate + CO2 |
| Subcellular location | Endoplasmic reticulum lumen (inferred from collagen hydroxylases) |
| Enzyme family | 2-oxoglutarate-dependent dioxygenase superfamily |
What Is GO:0019797?
GO:0019797 describes the catalytic activity of an enzyme that hydroxylates the third carbon of proline residues within procollagen, using 2-oxoglutarate as a cosubstrate and releasing succinate and CO2 [1,3]. This activity is also known as prolyl 3-hydroxylase and is distinct from prolyl 4-hydroxylase, which modifies the fourth carbon.
Why Is procollagen-proline 3-dioxygenase activity Important in Cell Biology?
Procollagen-proline 3-dioxygenase activity is essential for proper collagen folding and stability, and its dysregulation is associated with a spectrum of human diseases, including osteogenesis imperfecta, Ehlers-Danlos syndrome, and fibrosis [1,7]. Understanding this activity provides insights into extracellular matrix biology and offers potential therapeutic targets for fibrotic and connective tissue disorders.
• Collagen 3-hydroxylation is critical for triple-helix stability and fibril formation.
• Mutations in prolyl 3-hydroxylase genes cause recessive osteogenesis imperfecta.
• Altered 3-hydroxylation is observed in fibrotic tissues and may serve as a biomarker.
• The enzyme is a potential target for anti-fibrotic therapies.
• Prolyl 3-hydroxylase activity influences cancer cell migration and metastasis.
• The modification is conserved across species, highlighting its fundamental role.
• Defects in 3-hydroxylation lead to connective tissue fragility.
• Studying this activity aids in tissue engineering and regenerative medicine.
What Happens During procollagen-proline 3-dioxygenase activity?
Substrate recognition and binding
In simple terms: The enzyme finds and grabs the collagen protein at specific proline spots.
Prolyl 3-hydroxylase enzymes recognize procollagen chains, particularly the X-Pro-Gly repeats, and bind to specific proline residues, such as Pro986 in the alpha-1(I) chain. This binding is mediated by the enzyme's active site and accessory proteins like CRTAP and cyclophilin B.
Catalytic hydroxylation
In simple terms: The enzyme uses oxygen and a helper molecule to add a hydroxyl group to proline.
The enzyme utilizes a ferrous iron center to activate molecular oxygen, which then hydroxylates the proline substrate in a 2-oxoglutarate-dependent manner, producing trans-3-hydroxy-L-proline, succinate, and CO2. This reaction is stereospecific and requires ascorbate as a reducing agent to maintain iron in the active Fe(II) state.
Cofactor regeneration and product release
In simple terms: After the reaction, the enzyme releases the modified collagen and resets its helpers.
Following hydroxylation, the enzyme releases the 3-hydroxylated procollagen, succinate, and CO2. Ascorbate helps regenerate the iron center, allowing the enzyme to catalyze multiple rounds.
Key Genes Involved in GO:0019797 procollagen-proline 3-dioxygenase activity
The following genes encode enzymes or accessory proteins directly involved in procollagen-proline 3-dioxygenase activity.
| Gene | Major Role | Research Relevance |
|---|---|---|
| P3H1 (LEPRE1) | Catalytic subunit of prolyl 3-hydroxylase complex | Mutations cause osteogenesis imperfecta type VIII |
| P3H2 (LEPREL1) | Prolyl 3-hydroxylase with tissue-specific expression | Associated with collagen IV hydroxylation and basement membrane integrity |
| P3H3 (LEPREL2) | Prolyl 3-hydroxylase involved in collagen synthesis | Potential role in cancer and fibrosis |
| CRTAP | Cartilage-associated protein, essential for P3H1 activity | Mutations cause recessive osteogenesis imperfecta |
| PPIB (Cyclophilin B) | Peptidyl-prolyl isomerase, required for P3H1 complex | Defects lead to osteogenesis imperfecta |
| COL1A1 | Major substrate for 3-hydroxylation (Pro986) | Mutations cause osteogenesis imperfecta |
| COL1A2 | Substrate for 3-hydroxylation | Mutations cause connective tissue disorders |
| COL4A1 | Substrate for P3H2-mediated hydroxylation | Mutations linked to vascular and renal diseases |
| COL4A2 | Substrate for P3H2 | Mutations linked to porencephaly |
| COL3A1 | Substrate for 3-hydroxylation | Mutations cause Ehlers-Danlos syndrome |
| COL5A1 | Substrate for 3-hydroxylation | Mutations cause classical Ehlers-Danlos syndrome |
| COL5A2 | Substrate for 3-hydroxylation | Mutations cause classical Ehlers-Danlos syndrome |
| COL6A1 | Substrate for 3-hydroxylation | Mutations cause Bethlem myopathy |
| COL6A2 | Substrate for 3-hydroxylation | Mutations cause Ullrich congenital muscular dystrophy |
| COL6A3 | Substrate for 3-hydroxylation | Mutations cause collagen VI-related myopathies |
How Is procollagen-proline 3-dioxygenase activity Regulated?
Prolyl 3-hydroxylase activity is regulated at multiple levels. Expression of P3H genes varies across tissues and developmental stages. The activity requires assembly of a complex with CRTAP and cyclophilin B for full function. Additionally, enzyme activity can be modulated by oxygen tension, iron availability, and ascorbate levels, which affect the 2-oxoglutarate-dependent dioxygenase reaction. In transformed cells, proline 3-hydroxylation is downregulated compared to normal cells.
procollagen-proline 3-dioxygenase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| P3H1 | Osteogenesis imperfecta type VIII | Knockout mouse, patient-derived iPSCs |
| CRTAP | Recessive osteogenesis imperfecta | CRISPR knockout in mesenchymal stem cells |
| PPIB | Osteogenesis imperfecta | Point mutation knock-in in HEK293 |
| P3H3 | Cancer progression | Overexpression in cancer cell lines |
| COL1A1 | Osteogenesis imperfecta | Knock-in of Pro986 mutation |
Osteogenesis Imperfecta
Mutations in P3H1, CRTAP, and PPIB cause recessive forms of osteogenesis imperfecta, characterized by bone fragility and skeletal deformities. These mutations impair prolyl 3-hydroxylation of type I collagen, leading to defective collagen folding and bone matrix instability.
Fibrosis
Altered prolyl 3-hydroxylation is observed in hepatic fibrosis, where serum procollagen type III peptide serves as a marker of fibrogenesis. Dysregulated collagen synthesis and modification contribute to excessive extracellular matrix deposition in fibrotic tissues.
Cancer
Proline 3-hydroxylation and prolyl 3-hydroxylase activities are reduced in transformed cells, suggesting a role in tumorigenesis. Downregulation of P3H3 has been implicated in cancer progression and metastasis.
From procollagen-proline 3-dioxygenase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does P3H1 loss affect collagen 3-hydroxylation? | P3H1 knockout HEK293 or fibroblasts |
| What is the effect of Pro986 mutation on collagen stability? | COL1A1 point mutation knock-in |
| Can P3H2 overexpression rescue basement membrane defects? | P3H2 overexpression in COL4A1 mutant cells |
| How does CRTAP deficiency impact P3H1 activity? | CRTAP knockout mouse embryonic fibroblasts |
| Does P3H3 knockdown alter cancer cell migration? | P3H3 shRNA or CRISPR KO in cancer cells |
| Can tagged P3H1 be used to study complex assembly? | Knock-in of FLAG-tagged P3H1 |
How to Study the procollagen-proline 3-dioxygenase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Mass spectrometry | 3-hydroxyproline content in collagen | Quantification in tissues and cell cultures |
| Enzymatic assay | Prolyl 3-hydroxylase activity | Kinetic studies with recombinant enzymes |
| CRISPR knockout | Gene function in hydroxylation | Loss-of-function studies in cell lines |
| RNA-seq | Expression of P3H genes | Tissue-specific expression profiling |
| Immunofluorescence | Protein localization | Subcellular distribution of P3H enzymes |
| Western blot | Protein levels and modification | Validation of knockout or overexpression |
| CRISPR library screening | Genome-wide identification of regulators | Discovery of novel components in collagen modification |
Mass Spectrometry
Mass spectrometry-based proteomics can detect and quantify 3-hydroxyproline in collagen peptides, providing direct evidence of prolyl 3-hydroxylase activity.
Enzymatic Assays
In vitro assays using recombinant P3H enzymes and synthetic peptide substrates measure hydroxylation activity by monitoring 2-oxoglutarate consumption or succinate production.
CRISPR Screening
Genome-wide CRISPR knockout screens can identify genes required for collagen 3-hydroxylation and extracellular matrix integrity.
Immunoblotting and Immunofluorescence
Antibodies specific to 3-hydroxyproline or tagged P3H proteins allow detection of modification levels and subcellular localization in cells and tissues.
How CRISPR Can Be Used to Study GO:0019797 procollagen-proline 3-dioxygenase activity
Knockout
CRISPR knockout of P3H1, P3H2, P3H3, CRTAP, or PPIB in cell lines such as HEK293 or fibroblasts abolishes prolyl 3-hydroxylase activity, enabling studies of collagen stability and extracellular matrix assembly.
Point Mutation
Introducing disease-associated point mutations (e.g., in COL1A1 Pro986) via CRISPR base editing or HDR allows precise modeling of osteogenesis imperfecta and analysis of 3-hydroxylation defects.
Knock-in
Knock-in of epitope tags (e.g., FLAG, HA) into endogenous P3H1 or CRTAP loci facilitates affinity purification and interactome studies of the prolyl 3-hydroxylase complex.
Overexpression
CRISPR activation or lentiviral overexpression of P3H enzymes can rescue hydroxylation defects or enhance collagen modification, providing gain-of-function models for fibrosis and cancer research.
How EDITGENE Supports procollagen-proline 3-dioxygenase activity Research
Researchers studying procollagen-proline 3-dioxygenase activity-related genes often need to determine whether a candidate gene is causally involved in collagen modification, extracellular matrix remodeling, or disease pathogenesis. EDITGENE provides comprehensive CRISPR-based services to accelerate these investigations.
Contact EDITGENE today to design your custom CRISPR model for procollagen-proline 3-dioxygenase activity research.
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| P3H1 Knockout HEK293 Cell Line | EDJ-KQ11360 | Human | 64175 | Details Get a Quote |
| P3H2 Knockout HEK293 Cell Line | EDJ-KQ14655 | Human | 55214 | Details Get a Quote |
| P3H1 Knockout A-549 Cell Line | EDJ-KQ40794 | Human | 64175 | Details Get a Quote |
| P3H1 Knockout HCT 116 Cell Line | EDJ-KQ40795 | Human | 64175 | Details Get a Quote |
| P3H1 Knockout HeLa Cell Line | EDJ-KQ40796 | Human | 64175 | Details Get a Quote |
| P3H2 Knockout A-549 Cell Line | EDJ-KQ44935 | Human | 55214 | Details Get a Quote |
| P3H2 Knockout HCT 116 Cell Line | EDJ-KQ44936 | Human | 55214 | Details Get a Quote |
| P3H2 Knockout HeLa Cell Line | EDJ-KQ44937 | Human | 55214 | Details Get a Quote |
| P3H3 Knockout HEK293 Cell Line | EDJ-KQ50982 | Human | 10536 | Details Get a Quote |
| P3H3 Knockout HeLa Cell Line | EDJ-KQ55424 | Human | 10536 | Details Get a Quote |
| P3H3 Knockout A-549 Cell Line | EDJ-KQ63903 | Human | 10536 | Details Get a Quote |
| P3H3 Knockout HCT 116 Cell Line | EDJ-KQ72362 | Human | 10536 | Details Get a Quote |
Frequently Asked Questions About procollagen-proline 3-dioxygenase activity
What is procollagen-proline 3-dioxygenase activity?
It is the enzymatic activity that hydroxylates proline residues in procollagen to form trans-3-hydroxy-L-proline, a post-translational modification important for collagen stability.
What genes are involved in procollagen-proline 3-dioxygenase activity?
Key genes include P3H1, P3H2, P3H3, CRTAP, and PPIB, which encode components of the prolyl 3-hydroxylase complex.
What is the GO ID for procollagen-proline 3-dioxygenase activity?
The GO ID is GO:0019797.
What cofactors are required for prolyl 3-hydroxylase activity?
The enzyme requires Fe(II), 2-oxoglutarate, molecular oxygen, and ascorbate.
How is prolyl 3-hydroxylase different from prolyl 4-hydroxylase?
Prolyl 3-hydroxylase modifies the third carbon of proline, while prolyl 4-hydroxylase modifies the fourth carbon; they are distinct enzymes with different substrate specificities.
What diseases are associated with defects in prolyl 3-hydroxylation?
Mutations in P3H1, CRTAP, and PPIB cause recessive osteogenesis imperfecta, and altered hydroxylation is linked to fibrosis and cancer [1,7].
How can I study prolyl 3-hydroxylase activity in the lab?
Common methods include mass spectrometry to detect 3-hydroxyproline, enzymatic assays with recombinant enzymes, and CRISPR knockout models [1,3].
What cell models are available for prolyl 3-hydroxylase research?
EDITGENE offers knockout, point mutation, knock-in, and overexpression cell models for P3H genes and collagen substrates.
Is prolyl 3-hydroxylation conserved across species?
Yes, prolyl 3-hydroxylase genes are expressed in embryonic and adult mouse tissues, indicating evolutionary conservation.
Can CRISPR be used to model osteogenesis imperfecta caused by P3H1 mutations?
Yes, CRISPR knockout or point mutation knock-in of P3H1 in cell lines or iPSCs can model osteogenesis imperfecta and study collagen defects.
Conclusion
Procollagen-proline 3-dioxygenase activity (GO:0019797) is a specialized enzymatic function critical for collagen post-translational modification and extracellular matrix integrity. Its dysregulation contributes to skeletal disorders, fibrosis, and cancer, making it a compelling target for basic and translational research. Leveraging CRISPR-based models and EDITGENE services can accelerate discoveries in this field.
References
- 1. Hudson DM et al.. 2013. Collagen prolyl 3-hydroxylation: a major role for a minor post-translational modification?. Connect Tissue Res 54(4-5):245-51 PMID: 23772978
- 2. Majamaa K et al.. 1982. Regulation of proline 3-hydroxylation and prolyl 3-hydroxylase and 4-hydroxylase activities in transformed cells.. Biochem J 206(3):499-503 PMID: 6293467
- 3. Clifton IJ et al.. 2001. Structure of proline 3-hydroxylase. Evolution of the family of 2-oxoglutarate dependent oxygenases.. Eur J Biochem 268(24):6625-36 PMID: 11737217
- 4. Bell E et al.. 1983. The reconstitution of living skin.. J Invest Dermatol 81(1 Suppl):2s-10s PMID: 6306115
- 6. Kivirikko KI et al.. 1998. Collagen hydroxylases and the protein disulfide isomerase subunit of prolyl 4-hydroxylases.. Adv Enzymol Relat Areas Mol Biol 72:325-98 PMID: 9559057
- 7. Torres-Salinas M et al.. 1986. Serum procollagen type III peptide as a marker of hepatic fibrogenesis in alcoholic hepatitis.. Gastroenterology 90(5 Pt 1):1241-6 PMID: 3007261
- 8. Vranka J et al.. 2009. Expression of prolyl 3-hydroxylase genes in embryonic and adult mouse tissues.. Cell Struct Funct 34(2):97-104 PMID: 19652424
