GO:0033823 procollagen glucosyltransferase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0033823 procollagen glucosyltransferase activity catalyzes the transfer of glucose from UDP-glucose to galactosylhydroxylysine residues on procollagen, forming glucosylgalactosylhydroxylysine.
• The enzyme responsible is multifunctional lysyl hydroxylase 3 (LH3, gene PLOD3), which also possesses lysyl hydroxylase and galactosyltransferase activities.
• Specific amino acids within the LH3 catalytic domain are critical for glucosyltransferase activity, distinguishing it from its other enzymatic functions.
• Elevated procollagen glucosyltransferase activity is observed in various cancers, including breast cancer and hepatocellular carcinoma, and in response to prolonged exercise.
• A collagen glucosyltransferase drives lung adenocarcinoma progression in mice, highlighting its potential as a therapeutic target.
• Research tools include enzyme activity assays, CRISPR knockout/knock-in models, and bioinformatics for studying PLOD3 and related genes.
Description
Procollagen glucosyltransferase activity (GO:0033823) is a molecular function that catalyzes the transfer of glucose from UDP-glucose to galactosylhydroxylysine residues on procollagen, generating glucosylgalactosylhydroxylysine. This modification is essential for proper collagen folding and cross-linking, influencing the stability and function of the extracellular matrix. The enzyme responsible for this activity is lysyl hydroxylase 3 (LH3), encoded by the PLOD3 gene, which is a multifunctional protein also exhibiting lysyl hydroxylase and galactosyltransferase activities. Understanding this activity is crucial for researchers studying connective tissue biology, cancer progression, and fibrotic diseases. The reaction specifically requires UDP-glucose as the glucose donor and acts on procollagen substrates that already carry galactosylhydroxylysine modifications. Dysregulation of this activity has been linked to various pathological conditions, making it a target for therapeutic intervention and a biomarker for disease progression.
procollagen glucosyltransferase activity At A Glance
| GO ID | GO:0033823 |
|---|---|
| GO term | procollagen glucosyltransferase activity |
| Ontology | molecular_function |
| Synonym | collagen glucosyltransferase activity; collagen hydroxylysyl glucosyltransferase activity; galactosylhydroxylysine glucosyltransferase activity; UDP-glucose:5-(D-galactosyloxy)-L-lysine-procollagen D-glucosyltransferase activity |
| Major function | Catalyzes the transfer of glucose from UDP-glucose to galactosylhydroxylysine residues on procollagen, forming glucosylgalactosylhydroxylysine. |
| Enzyme | Lysyl hydroxylase 3 (LH3), encoded by PLOD3. |
| Substrate | UDP-glucose and 5-(D-galactosyloxy)-L-lysine-procollagen. |
| Product | UDP and 1,2-D-glucosyl-5-D-(galactosyloxy)-L-lysine-procollagen. |
| Cofactors | Not specified in QuickGO definition; however, LH3 requires Fe2+ and ascorbate for its lysyl hydroxylase activity, but glucosyltransferase activity may not require these. |
What Is GO:0033823?
Procollagen glucosyltransferase activity is defined as the catalysis of the reaction: UDP-glucose + 5-(D-galactosyloxy)-L-lysine-procollagen = UDP + 1,2-D-glucosyl-5-D-(galactosyloxy)-L-lysine-procollagen. In simpler terms, it is an enzyme activity that adds a glucose molecule to a specific sugar-modified lysine residue on procollagen, using UDP-glucose as the donor. This modification is part of the post-translational processing of collagen, contributing to the formation of glucosylgalactosylhydroxylysine, which is important for collagen structure and function.
Why Is procollagen glucosyltransferase activity Important in Cell Biology?
Procollagen glucosyltransferase activity is important because it is a key step in collagen post-translational modification, affecting collagen stability and interactions. Alterations in this activity have been implicated in cancer progression, with a collagen glucosyltransferase driving lung adenocarcinoma in mice, and elevated activity observed in breast cancer and hepatocellular carcinoma. It also increases with prolonged exercise, reflecting connective tissue remodeling. Thus, understanding this activity provides insights into extracellular matrix biology and disease mechanisms.
• Essential for collagen maturation and extracellular matrix stability.
• Elevated in breast cancer tissues and sera, suggesting a biomarker role.
• Increased in hepatocellular carcinoma, linking to liver cancer biology.
• Drives lung adenocarcinoma progression in mouse models.
• Responds to prolonged exercise, indicating a role in tissue adaptation.
• Target for therapeutic intervention in fibrosis and cancer.
• Multifunctional enzyme LH3 also affects other collagen modifications.
• Specific amino acids determine glucosyltransferase activity, enabling selective targeting.
• Viral homologs exist, e.g., in Acanthamoeba polyphaga mimivirus, expanding evolutionary insights.
• Surface-associated activity in malignant fibroblasts suggests a role in tumor microenvironment.
Molecular Mechanism of procollagen glucosyltransferase activity
Substrate Recognition and Binding
In simple terms: The enzyme finds and attaches to the collagen molecule at a specific modified lysine.
Procollagen glucosyltransferase activity specifically recognizes 5-(D-galactosyloxy)-L-lysine residues on procollagen. This substrate specificity is mediated by the enzyme's active site, which accommodates the galactosylhydroxylysine moiety. Studies on LH3 have identified amino acids important for catalytic activity, including those involved in substrate binding.
Catalytic Transfer of Glucose
In simple terms: The enzyme takes a glucose molecule from UDP-glucose and attaches it to the collagen sugar chain.
The enzyme catalyzes the transfer of glucose from UDP-glucose to the galactosylhydroxylysine residue, forming glucosylgalactosylhydroxylysine and releasing UDP. This reaction is part of the sequential glycosylation of collagen, following galactosylation. The catalytic mechanism involves conserved residues in the LH3 glucosyltransferase domain.
Role of Multifunctional LH3
In simple terms: One protein, LH3, does several jobs, including adding glucose to collagen.
Lysyl hydroxylase 3 (LH3) is a multifunctional enzyme that possesses lysyl hydroxylase, galactosyltransferase, and glucosyltransferase activities. The glucosyltransferase activity is one of its key functions, and mutations affecting this activity can impact collagen modification. The enzyme's multifunctionality suggests coordinated regulation of collagen post-translational modifications.
Regulation and Cofactors
In simple terms: The enzyme's activity can be turned up or down, and it may need certain helpers.
The glucosyltransferase activity of LH3 may be regulated by factors affecting enzyme expression or post-translational modifications. While the lysyl hydroxylase activity requires Fe2+ and ascorbate, the glucosyltransferase activity may not have the same cofactor requirements. Specific amino acid substitutions can abolish glucosyltransferase activity without affecting other functions, indicating distinct regulatory mechanisms.
Key Genes Involved in GO:0033823 procollagen glucosyltransferase activity
The following genes and proteins are directly involved in or associated with procollagen glucosyltransferase activity.
| Gene | Major Role | Research Relevance |
|---|---|---|
| PLOD3 | Encodes lysyl hydroxylase 3 (LH3), the enzyme with procollagen glucosyltransferase activity. | Central to collagen modification; mutations linked to connective tissue disorders and cancer. |
| COL1A1 | Encodes type I collagen alpha-1 chain, a substrate for glucosylation. | Mutations cause osteogenesis imperfecta; model for studying collagen processing. |
| COL1A2 | Encodes type I collagen alpha-2 chain, another substrate. | Similar to COL1A1, relevant for collagen-related diseases. |
| COL3A1 | Encodes type III collagen, a substrate; increased activity observed in exercise. | Linked to Ehlers-Danlos syndrome; marker for tissue remodeling. |
| COL5A1 | Encodes type V collagen, potential substrate. | Involved in connective tissue disorders; may affect glucosylation. |
| COL5A2 | Encodes type V collagen alpha-2 chain. | Similar to COL5A1. |
| COL4A1 | Encodes type IV collagen, basement membrane component. | May undergo glucosylation; relevant in cancer and vascular diseases. |
| COL4A2 | Encodes type IV collagen alpha-2 chain. | Similar to COL4A1. |
| COL6A1 | Encodes type VI collagen, microfibrillar component. | Mutations cause myopathies; potential substrate. |
| COL6A2 | Encodes type VI collagen alpha-2 chain. | Similar to COL6A1. |
| COL6A3 | Encodes type VI collagen alpha-3 chain. | Similar to COL6A1. |
| PLOD1 | Encodes lysyl hydroxylase 1, related enzyme. | Mutations cause Ehlers-Danlos syndrome type VI; may compensate. |
| PLOD2 | Encodes lysyl hydroxylase 2, related enzyme. | Involved in fibrosis and cancer; potential cross-talk. |
| LH3 (protein) | Multifunctional enzyme with glucosyltransferase activity. | Direct target for activity assays and inhibitor development. |
| UDP-glucose | Glucose donor substrate. | Metabolic labeling and enzyme assays. |
| Galactosylhydroxylysine | Acceptor substrate on procollagen. | Substrate specificity studies. |
| Glucosylgalactosylhydroxylysine | Product of the reaction. | Biomarker for collagen modification. |
| Mimivirus collagen glucosyltransferase | Viral homolog with similar activity. | Evolutionary and structural studies. |
How Is procollagen glucosyltransferase activity Regulated?
The regulation of procollagen glucosyltransferase activity is not fully understood, but it is likely controlled at the level of PLOD3 gene expression and enzyme post-translational modifications. The multifunctional nature of LH3 suggests that its glucosyltransferase activity may be independently regulated from its other enzymatic functions, as specific amino acid changes can abolish glucosyltransferase activity without affecting lysyl hydroxylase or galactosyltransferase activities. Additionally, the activity increases in response to prolonged exercise, indicating physiological regulation. Further research is needed to identify specific regulatory pathways.
procollagen glucosyltransferase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| PLOD3 | Connective tissue disorders, cancer | Knockout mice, patient-derived fibroblasts |
| COL1A1 | Osteogenesis imperfecta | Point mutation knock-in mice |
| COL3A1 | Ehlers-Danlos syndrome | Knockout mice |
| PLOD3 | Lung adenocarcinoma | Xenograft models with overexpression |
| PLOD3 | Breast cancer | Cell lines and patient sera |
Cancer Progression and Metastasis
Procollagen glucosyltransferase activity is elevated in several cancers. In breast cancer, increased activity was found in tumor tissues and sera of patients. In hepatocellular carcinoma, liver galactosylhydroxylysyl glucosyltransferase activity is elevated. A collagen glucosyltransferase drives lung adenocarcinoma progression in mice, suggesting a role in tumor growth and metastasis. These findings indicate that this activity contributes to the tumor microenvironment and could be a therapeutic target.
Connective Tissue Disorders
Mutations in PLOD3, the gene encoding the enzyme with procollagen glucosyltransferase activity, can cause connective tissue disorders. LH3 deficiency leads to abnormal collagen modification, affecting skin, blood vessels, and bones. The glucosyltransferase activity is part of the multifunctional LH3, and its loss may contribute to the disease phenotype.
Exercise and Tissue Remodeling
Prolonged exercise increases the activity of galactosylhydroxylysyl glucosyltransferase and the concentration of type III procollagen aminopropeptide in human serum, reflecting enhanced collagen synthesis and remodeling in response to physical stress. This physiological regulation highlights the role of this activity in tissue adaptation.
From procollagen glucosyltransferase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of glucosyltransferase activity affect collagen stability? | PLOD3 knockout cell lines (e.g., HEK293, fibroblasts) |
| Which amino acids are critical for catalytic activity? | Point mutations in PLOD3 (e.g., in catalytic domain) |
| Can a specific point mutation abolish glucosyltransferase activity without affecting other functions? | Knock-in mice with point mutation in PLOD3 |
| How does glucosyltransferase activity affect cancer progression? | Overexpression of PLOD3 in lung cancer cell lines and mouse models |
| What is the role of glucosyltransferase in exercise-induced remodeling? | Exercise intervention studies in humans and mice |
| Can we track the enzyme in live cells? | Tagged knock-in of PLOD3 with fluorescent protein |
How to Study the procollagen glucosyltransferase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Enzyme activity assay | Glucosyltransferase activity using UDP-glucose and substrate | Quantifying activity in tissues and sera |
| CRISPR knockout | Loss of PLOD3 function | Studying collagen modification and disease models |
| CRISPR point mutation | Specific amino acid changes in PLOD3 | Dissecting catalytic residues |
| CRISPR knock-in | Tagged or mutant PLOD3 | Tracking enzyme localization and function |
| Mass spectrometry | Glucosylgalactosylhydroxylysine levels | Biomarker discovery and validation |
| Bioinformatics | Sequence conservation and homology | Identifying functional domains |
| Immunohistochemistry | Protein expression and localization | Tissue distribution studies |
| RNA-seq | PLOD3 expression levels | Transcriptional regulation studies |
Enzyme Activity Assays
Procollagen glucosyltransferase activity can be measured using radioactive or fluorescent assays that monitor the transfer of glucose from UDP-glucose to galactosylhydroxylysine-containing substrates. These assays are used to quantify activity in tissues, cells, and sera, as demonstrated in breast cancer and hepatocellular carcinoma studies.
CRISPR-Cas9 Genome Editing
CRISPR-Cas9 can be used to generate knockout, point mutation, or knock-in models to study the function of PLOD3 and its glucosyltransferase activity. For example, knockout of PLOD3 in cell lines can reveal its role in collagen modification, while point mutations can dissect catalytic residues.
Bioinformatics and Comparative Genomics
Bioinformatic analyses can identify conserved residues and homologs of collagen glucosyltransferases, as shown in the identification of a viral homolog from Acanthamoeba polyphaga mimivirus. These approaches help in understanding evolutionary relationships and predicting functional sites.
Proteomics and Mass Spectrometry
Mass spectrometry can detect and quantify glucosylgalactosylhydroxylysine on collagen, providing a direct readout of glucosyltransferase activity in biological samples. This method is useful for validating enzyme activity and studying post-translational modifications.
How CRISPR Can Be Used to Study GO:0033823 procollagen glucosyltransferase activity
Knockout
CRISPR knockout of PLOD3 eliminates procollagen glucosyltransferase activity, allowing researchers to study its role in collagen synthesis and disease. Knockout cell lines and mouse models can reveal compensatory mechanisms and phenotypic changes.
Point Mutation
Point mutations in PLOD3 can selectively abolish glucosyltransferase activity while preserving other functions. This approach helps identify critical catalytic residues and understand the specific contribution of glucosylation to collagen biology.
Knock-in
Knock-in of tagged or mutant PLOD3 enables tracking of the enzyme in live cells and tissues. Fluorescent tags allow visualization of subcellular localization and dynamics, while mutant knock-ins can model human mutations.
Overexpression
Overexpression of PLOD3 in cancer cell lines and mouse models can drive tumor progression, as shown in lung adenocarcinoma. This model is useful for testing inhibitors and understanding the role of glucosyltransferase activity in cancer.
How EDITGENE Supports procollagen glucosyltransferase activity Research
Researchers studying procollagen glucosyltransferase activity-related genes often need to determine whether a candidate gene is causally involved in collagen modification, cancer progression, or connective tissue disorders. EDITGENE provides comprehensive CRISPR services to create precise cellular and animal models for such investigations.
Contact EDITGENE today to design your custom CRISPR model for procollagen glucosyltransferase activity research.
Frequently Asked Questions About procollagen glucosyltransferase activity
What is procollagen glucosyltransferase activity?
It is an enzyme activity that transfers glucose from UDP-glucose to galactosylhydroxylysine residues on procollagen, forming glucosylgalactosylhydroxylysine, as defined by GO:0033823.
What genes are involved in procollagen glucosyltransferase activity?
The primary gene is PLOD3, which encodes lysyl hydroxylase 3 (LH3), a multifunctional enzyme with glucosyltransferase activity.
Which enzyme catalyzes procollagen glucosyltransferase activity?
Lysyl hydroxylase 3 (LH3), encoded by PLOD3, catalyzes this reaction.
What is the role of procollagen glucosyltransferase activity in cancer?
It is elevated in breast cancer and hepatocellular carcinoma, and drives lung adenocarcinoma progression in mice, suggesting a role in tumor growth.
How is procollagen glucosyltransferase activity measured?
It can be measured using enzyme activity assays that monitor the transfer of glucose from UDP-glucose to collagen substrates, often with radioactive or fluorescent labels.
What diseases are associated with PLOD3 mutations?
Mutations in PLOD3 can cause connective tissue disorders due to defective collagen modification.
Does exercise affect procollagen glucosyltransferase activity?
Yes, prolonged exercise increases the activity of galactosylhydroxylysyl glucosyltransferase in human serum, reflecting collagen remodeling.
What are the substrates of procollagen glucosyltransferase?
The substrates are UDP-glucose and 5-(D-galactosyloxy)-L-lysine-procollagen.
Can CRISPR be used to study procollagen glucosyltransferase activity?
Yes, CRISPR knockout, point mutation, and knock-in models can be used to dissect the function of PLOD3 and its glucosyltransferase activity.
Are there viral homologs of procollagen glucosyltransferase?
Yes, a collagen galactosylhydroxylysyl glucosyltransferase has been identified in Acanthamoeba polyphaga mimivirus.
Conclusion
Procollagen glucosyltransferase activity (GO:0033823) is a critical enzymatic function in collagen post-translational modification, mediated by the multifunctional enzyme LH3 (PLOD3). Its dysregulation is linked to cancer progression and connective tissue disorders, making it a target for therapeutic development. Researchers can leverage CRISPR-based models and biochemical assays to further explore its mechanisms and roles in health and disease.
References
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- 2. Guo HF et al.. 2021. A collagen glucosyltransferase drives lung adenocarcinoma progression in mice.. Commun Biol 4(1):482 PMID: 33875777
- 3. Wang C et al.. 2002. Identification of amino acids important for the catalytic activity of the collagen glucosyltransferase associated with the multifunctional lysyl hydroxylase 3 (LH3).. J Biol Chem 277(21):18568-73 PMID: 11896059
- 4. Heikkinen J et al.. 2000. Lysyl hydroxylase 3 is a multifunctional protein possessing collagen glucosyltransferase activity.. J Biol Chem 275(46):36158-63 PMID: 10934207
- 5. Bolarin DM. 1983. Immunoreactive prolyl hydroxylase protein and galactosylhydroxylysyl glucosyltransferase activity in breast tissues and sera of patients with primary breast cancer.. Res Commun Chem Pathol Pharmacol 39(3):493-502 PMID: 6304825
- 6. Bolarin DM. 1983. Elevation of liver-galactosylhydroxylysyl glucosyltransferase activity in human primary hepatocellular carcinoma.. Int J Biochem 15(10):1291-3 PMID: 6313446
- 7. Wu W et al.. 2022. Comparative genomic and biochemical analyses identify a collagen galactosylhydroxylysyl glucosyltransferase from Acanthamoeba polyphaga mimivirus.. Sci Rep 12(1):16806 PMID: 36207453
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