GO:0009173 pyrimidine ribonucleoside monophosphate metabolic process: Nucleotide Biosynthesis Pathway, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0009173 describes the chemical reactions and pathways involving pyrimidine ribonucleoside monophosphates, such as UMP and CMP, which are essential for RNA synthesis and nucleotide homeostasis.
• The pathway includes de novo synthesis, salvage, and interconversion reactions that maintain cellular pyrimidine pools.
• Key enzymes include UMPS, NUDT22, and CMPK1, which are implicated in cancer metabolism and therapeutic resistance.
• Dysregulation of pyrimidine metabolism is linked to cancer, viral infections, and developmental disorders.
• CRISPR-based models (knockout, point mutation, knock-in, overexpression) enable functional dissection of this pathway in disease contexts.
• Understanding this process supports drug discovery, including antimetabolites and nucleotide analogs used in oncology and antiviral therapy.
Description
Pyrimidine ribonucleoside monophosphate metabolic process (GO:0009173) encompasses the biochemical reactions that synthesize, interconvert, and degrade pyrimidine ribonucleoside monophosphates, which are fundamental building blocks of RNA and critical regulators of cellular metabolism. These nucleotides, including uridine monophosphate (UMP) and cytidine monophosphate (CMP), are produced through de novo biosynthesis or salvage pathways and are essential for nucleic acid synthesis, energy transfer, and signaling. Researchers study this process to understand how cells maintain nucleotide balance, respond to metabolic stress, and how disruptions contribute to diseases such as cancer and viral infections. The pathway is also a target for therapeutic intervention, as evidenced by antimetabolite drugs and nucleotide analogs that interfere with pyrimidine metabolism. This article provides a comprehensive overview of GO:0009173, integrating authoritative QuickGO annotations with verified literature to support research and drug discovery.
pyrimidine ribonucleoside monophosphate metabolic process At A Glance
| GO ID | GO:0009173 |
|---|---|
| GO term | pyrimidine ribonucleoside monophosphate metabolic process |
| Ontology | biological_process |
| Synonym | pyrimidine ribonucleoside monophosphate metabolism |
| Major function | Synthesis and interconversion of pyrimidine ribonucleoside monophosphates for RNA and nucleotide pools |
| Key enzymes | UMPS, NUDT22, CMPK1, UPRT, UCK2 |
| Pathways | De novo pyrimidine biosynthesis, salvage pathway, nucleotide interconversion |
| Disease relevance | Cancer, viral infections, metabolic disorders |
| Research methods | CRISPR knockout, metabolomics, RNA-seq, enzymatic assays |
What Is GO:0009173?
GO:0009173, pyrimidine ribonucleoside monophosphate metabolic process, is defined as the chemical reactions and pathways involving pyrimidine ribonucleoside monophosphate, a compound consisting of a pyrimidine base linked to a ribose sugar esterified with phosphate on the sugar. This process includes the biosynthesis, salvage, interconversion, and degradation of pyrimidine ribonucleoside monophosphates, which are key intermediates in RNA synthesis and nucleotide metabolism.
Why Is pyrimidine ribonucleoside monophosphate metabolic process Important in Cell Biology?
Pyrimidine ribonucleoside monophosphate metabolism is essential for maintaining cellular nucleotide pools required for RNA synthesis, DNA repair, and cell proliferation. Dysregulation of this pathway is a hallmark of cancer, where increased pyrimidine salvage supports tumor growth and resistance to therapy. Moreover, viral pathogens often hijack host pyrimidine metabolism for replication, making this process a target for antiviral drugs. Understanding the regulatory mechanisms and enzyme functions within GO:0009173 can reveal therapeutic vulnerabilities and biomarkers for precision medicine.
• Provides precursors for RNA synthesis and nucleotide homeostasis.
• Supports rapid cell proliferation in cancer and immune cells.
• Enables salvage pathways that recycle pyrimidines, crucial under nutrient stress.
• Targeted by antimetabolite chemotherapies and antiviral nucleotide analogs.
• Involved in mitochondrial function and energy metabolism.
• Regulates immune cell function and antitumor immunity.
• Dysregulated in developmental disorders and rare metabolic diseases.
• Offers biomarkers for drug response and resistance.
• Facilitates viral RNA replication, a target for COVID-19 and HCV therapies.
• Enables CRISPR screening to identify synthetic lethal interactions.
What Happens During pyrimidine ribonucleoside monophosphate metabolic process?
De Novo Pyrimidine Biosynthesis
In simple terms: The cell builds pyrimidine nucleotides from scratch using simple molecules.
De novo pyrimidine biosynthesis begins with the formation of carbamoyl phosphate and proceeds through a series of enzymatic steps to produce UMP. Key enzymes include CAD, DHODH, and UMPS. UMPS, a bifunctional enzyme, catalyzes the final two steps of UMP synthesis and can form inactive biomolecular condensates that store metabolic potential. This pathway is essential for providing pyrimidines for RNA and DNA synthesis, particularly in proliferating cells.
Salvage Pathway
In simple terms: The cell recycles pre-existing pyrimidine bases and nucleosides to make nucleotides.
The salvage pathway recovers pyrimidines from nucleic acid turnover or extracellular sources. NUDT22, a Nudix hydrolase, promotes cancer growth by hydrolyzing pyrimidine nucleotides to facilitate salvage. This pathway is critical under conditions of high demand, such as in cancer cells, and represents a therapeutic target.
Interconversion and Regulation of Nucleotide Pools
In simple terms: The cell converts one pyrimidine nucleotide into another to balance its needs.
Pyrimidine ribonucleoside monophosphates undergo interconversion via kinases and nucleotidases. For example, UMP is phosphorylated to UDP and UTP, while CMP is generated from UMP via CTP synthase. These reactions are tightly regulated to maintain balanced nucleotide pools for RNA synthesis and metabolic signaling. Dysregulation can lead to genomic instability and disease.
Degradation and Turnover
In simple terms: The cell breaks down pyrimidine nucleotides to recycle components or dispose of excess.
Excess pyrimidine nucleotides are degraded through the action of nucleotidases and nucleosidases, ultimately yielding bases that can be salvaged or excreted. This turnover is important for preventing toxic accumulation and maintaining metabolic flexibility. NUDT22 has been implicated in the degradation of pyrimidine nucleotides to support cancer cell growth.
Key Genes Involved in GO:0009173 pyrimidine ribonucleoside monophosphate metabolic process
The following genes encode enzymes and transporters directly involved in pyrimidine ribonucleoside monophosphate metabolism, with roles in biosynthesis, salvage, and interconversion.
| Gene | Major Role | Research Relevance |
|---|---|---|
| UMPS | Bifunctional enzyme in de novo UMP synthesis | Forms condensates; target in cancer and antiviral research |
| NUDT22 | Pyrimidine salvage hydrolase | Promotes cancer growth; potential drug target |
| CMPK1 | Phosphorylates CMP to CDP | Maintains pyrimidine nucleotide pools; biomarker in cancer |
| UPRT | Converts uracil to UMP in salvage | Target for antimetabolite prodrugs |
| UCK2 | Phosphorylates uridine and cytidine | Activates nucleoside analogs in cancer therapy |
| CAD | Multienzyme complex for de novo synthesis | Regulated by mTOR; target in cancer |
| DHODH | Catalyzes dihydroorotate oxidation | Target for immunosuppressants and anticancer drugs |
| CTPS1 | Synthesizes CTP from UTP | Essential for lymphocyte proliferation |
| NT5C2 | Dephosphorylates pyrimidine nucleotides | Mutations in leukemia; drug resistance |
| ENT1 (SLC29A1) | Nucleoside transporter | Regulates adenosine uptake and pyrimidine synthesis |
| RRM1 | Ribonucleotide reductase subunit | Converts NDPs to dNDPs; target in cancer |
| RRM2 | Ribonucleotide reductase subunit | Cell cycle regulated; target in cancer |
| TYMS | Thymidylate synthase | Pyrimidine de novo synthesis; target of 5-FU |
| DPYD | Dihydropyrimidine dehydrogenase | Degrades pyrimidines; pharmacogenomic marker |
| SLC29A1 | Equilibrative nucleoside transporter 1 | Uptake of nucleoside drugs |
| SLC28A1 | Concentrative nucleoside transporter 1 | Nucleoside salvage and drug transport |
| NME1 | Nucleoside diphosphate kinase | Synthesizes nucleoside triphosphates |
How Is pyrimidine ribonucleoside monophosphate metabolic process Regulated?
Pyrimidine ribonucleoside monophosphate metabolism is regulated at multiple levels, including transcriptional control, allosteric feedback, and post-translational modifications. The mTOR pathway promotes de novo pyrimidine synthesis by activating CAD and other enzymes in response to growth signals. Conversely, the integrated stress response can suppress nucleotide synthesis under nutrient deprivation. Additionally, UMPS can form inactive biomolecular condensates that store metabolic potential, providing a mechanism for rapid reactivation when demand increases. NUDT22 activity is regulated by its expression levels and potentially by cellular redox state, influencing salvage capacity in cancer cells. These regulatory layers ensure that pyrimidine supply matches cellular needs for RNA synthesis and proliferation.
pyrimidine ribonucleoside monophosphate metabolic process and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| NUDT22 | Cancer growth and pyrimidine salvage | Knockout in cancer cell lines; xenograft models |
| UMPS | Orotic aciduria; cancer chemoresistance | Knock-in of patient mutations; condensate imaging |
| CTPS1 | Lymphoproliferative disorders | Knockout in T cells; proliferation assays |
| ENT1 (SLC29A1) | Antitumor immunity suppression | Overexpression in T cells; adenosine uptake assays |
| DPYD | 5-FU toxicity and pharmacogenomics | Point mutation knock-in in hepatocytes |
Cancer Metabolism and Chemoresistance
Dysregulated pyrimidine metabolism supports the high proliferative rate of cancer cells. NUDT22 promotes cancer growth by enhancing pyrimidine salvage, and its inhibition reduces tumor burden in preclinical models. UMPS condensates store metabolic potential, allowing cancer cells to survive chemotherapy and resume proliferation. Targeting these enzymes could overcome resistance to antimetabolites such as 5-fluorouracil.
Viral Infections and Antiviral Therapy
Many viruses, including SARS-CoV-2 and HCV, depend on host pyrimidine metabolism for RNA replication. Nucleotide analogs that mimic pyrimidine ribonucleoside monophosphates inhibit viral RNA polymerase and are used as antiviral drugs. Understanding host pyrimidine pathways can guide the development of broad-spectrum antivirals.
Immune Cell Function and Immunotherapy
Pyrimidine synthesis is critical for T-cell proliferation and effector function. Adenosine uptake through ENT1 suppresses antitumor immunity by limiting pyrimidine synthesis in T cells. Modulating pyrimidine metabolism may enhance the efficacy of cancer immunotherapy.
Inherited Metabolic Disorders
Rare mutations in pyrimidine metabolic enzymes, such as UMPS, cause orotic aciduria, a disorder characterized by anemia and developmental delay. Studies of UMPS condensates provide insight into how mutations affect enzyme function and metabolic storage.
From pyrimidine ribonucleoside monophosphate metabolic process-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does NUDT22 loss impair tumor growth? | NUDT22 knockout cancer cell lines and xenografts |
| How do UMPS mutations affect condensate formation? | Knock-in of patient mutations in cell lines |
| Can overexpression of CMPK1 rescue nucleotide depletion? | CMPK1 overexpression in cancer cells |
| What is the role of CTPS1 in T-cell proliferation? | CTPS1 knockout in primary T cells |
| Does ENT1 modulation enhance immunotherapy? | ENT1 overexpression or knockout in T cells |
| How does DPYD polymorphism affect drug toxicity? | DPYD point mutation knock-in in hepatocytes |
How to Study the pyrimidine ribonucleoside monophosphate metabolic process Process
| Method | What It Measures | Typical Application |
|---|---|---|
| LC-MS metabolomics | Levels of pyrimidine nucleotides | Pathway flux and drug effects |
| CRISPR knockout screens | Gene essentiality and synthetic lethality | Identify targets in cancer |
| RNA-seq | Gene expression changes | Transcriptional regulation of pathway |
| Enzymatic assays | Enzyme kinetics and inhibition | Drug discovery and mechanism |
| Fluorescence microscopy | Protein condensate formation | UMPS storage dynamics |
| Flow cytometry | Cell proliferation and viability | Assess pathway dependence |
| Western blot | Protein expression and phosphorylation | Regulation of enzymes |
| CRISPR interference (CRISPRi) | Gene knockdown effects | Fine-tune pathway gene expression |
Metabolomics and Nucleotide Profiling
Liquid chromatography-mass spectrometry (LC-MS) enables quantification of pyrimidine ribonucleoside monophosphates and related metabolites. This method is used to assess pathway activity, enzyme inhibition, and metabolic reprogramming in cancer cells.
CRISPR Screens and Functional Genomics
Genome-wide CRISPR knockout screens can identify genes essential for pyrimidine metabolism and synthetic lethal interactions. For example, screens in cancer cells treated with antimetabolites reveal resistance mechanisms.
RNA Sequencing and Transcriptomics
RNA-seq measures expression of pyrimidine metabolic genes and can reveal transcriptional responses to metabolic stress or drug treatment. It is often combined with metabolomics to link gene expression to pathway flux.
Enzymatic Assays and Protein Condensate Imaging
In vitro enzymatic assays measure activities of UMPS, NUDT22, and other enzymes. Fluorescence microscopy can visualize UMPS condensates and their dynamics under different metabolic conditions.
How CRISPR Can Be Used to Study GO:0009173 pyrimidine ribonucleoside monophosphate metabolic process
Knockout
CRISPR knockout of pyrimidine metabolic genes, such as NUDT22 or UMPS, enables loss-of-function studies to determine their role in cell proliferation, nucleotide pools, and drug sensitivity. For example, NUDT22 knockout reduces cancer cell growth and impairs salvage capacity.
Point Mutation
Introducing specific point mutations (e.g., in UMPS or DPYD) via CRISPR base editing or homology-directed repair allows modeling of inherited disorders and pharmacogenetic variants. This helps assess how mutations affect enzyme activity and drug metabolism.
Knock-in
Knock-in of tagged or reporter genes (e.g., GFP-UMPS) enables live-cell imaging of protein localization and condensate dynamics. It also allows study of mutant alleles under endogenous regulatory control.
Overexpression
CRISPR activation (CRISPRa) or cDNA overexpression can elevate expression of pyrimidine metabolic enzymes to study pathway activation, metabolic reprogramming, and resistance to antimetabolites.
How EDITGENE Supports pyrimidine ribonucleoside monophosphate metabolic process Research
Researchers studying pyrimidine ribonucleoside monophosphate metabolic process-related genes often need to determine whether a candidate gene is causally involved in pathway regulation, disease progression, or drug response. EDITGENE provides a comprehensive suite of CRISPR-based services to accelerate functional validation and therapeutic development.
Contact EDITGENE today to design your custom CRISPR model for pyrimidine ribonucleoside monophosphate metabolic process research.
Frequently Asked Questions About pyrimidine ribonucleoside monophosphate metabolic process
What is GO:0009173?
GO:0009173 is the Gene Ontology term for pyrimidine ribonucleoside monophosphate metabolic process, which includes the chemical reactions and pathways involving pyrimidine ribonucleoside monophosphates such as UMP and CMP.
What genes are involved in pyrimidine ribonucleoside monophosphate metabolic process?
Key genes include UMPS, NUDT22, CMPK1, UPRT, UCK2, CAD, DHODH, and CTPS1, among others.
Why is pyrimidine metabolism important in cancer?
Cancer cells often rely on increased pyrimidine salvage and synthesis to support rapid proliferation. NUDT22 promotes cancer growth through salvage, and UMPS condensates store metabolic potential for chemoresistance.
How can CRISPR be used to study pyrimidine metabolism?
CRISPR knockout, point mutation, knock-in, and overexpression models allow functional dissection of genes like NUDT22 and UMPS in disease contexts.
What diseases are linked to pyrimidine ribonucleoside monophosphate metabolism?
Diseases include cancer, viral infections, orotic aciduria, and immune disorders. Dysregulation supports tumor growth and viral replication.
What are the main enzymes in de novo pyrimidine synthesis?
CAD, DHODH, and UMPS are key enzymes. UMPS catalyzes the final steps and can form inactive condensates.
How is pyrimidine metabolism regulated?
It is regulated by mTOR signaling, allosteric feedback, and post-translational modifications. UMPS condensates provide a storage mechanism.
What methods are used to study pyrimidine ribonucleoside monophosphate metabolism?
LC-MS metabolomics, CRISPR screens, RNA-seq, enzymatic assays, and fluorescence microscopy are commonly used.
Can pyrimidine metabolism be targeted for antiviral therapy?
Yes, nucleotide analogs that mimic pyrimidine ribonucleoside monophosphates inhibit viral RNA polymerases, as seen with HCV and SARS-CoV-2.
What CRISPR services does EDITGENE offer for pyrimidine metabolism research?
EDITGENE provides knockout, point mutation, knock-in, overexpression, CRISPR library screening, and bioinformatics services for genes in this pathway.
Conclusion
Pyrimidine ribonucleoside monophosphate metabolic process (GO:0009173) is a central pathway in nucleotide metabolism, supporting RNA synthesis, cell proliferation, and metabolic homeostasis. Its dysregulation is implicated in cancer, viral infections, and immune disorders, making it a rich area for therapeutic targeting. Advances in CRISPR-based models and metabolomics continue to uncover new regulatory mechanisms and drug targets. EDITGENE offers comprehensive services to accelerate research on this pathway, from gene knockout to high-throughput screening.
References
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- 4. Kim-Holzapfel DM et al.. 2023. Human uridine 5'-monophosphate synthase stores metabolic potential in inactive biomolecular condensates.. J Biol Chem 299(3):102949 PMID: 36708921
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