GO:0006760 folic acid-containing compound metabolic process

Folic acid-containing compound metabolic process (GO:0006760) is a biological process ontology term that covers the chemical reactions and pathways involving folic acid-containing compounds, defined as heterocyclic compounds based on a pteroic acid skeleton conjugated with one or more L-glutamic acid or L-glutamate units. These compounds, collectively known as folates or vitamin B9 derivatives, function as essential cofactors in one-carbon transfer reactions that support nucleotide synthesis, amino acid metabolism, and methylation. Because rapidly dividing cells depend heavily on folate-dependent one-carbon metabolism, this process is a central node in cell biology and a major target of antimetabolite chemotherapy. The pathway is also clinically significant because folate status can modify the activity and toxicity of antifolate drugs. For example, cellular folate levels influence the polyglutamation of 5,10-dideazatetrahydrofolate, a mechanism that can determine resistance to folate antimetabolites. In parallel, folic acid supplementation has been evaluated for its effects on malaria susceptibility and severity among people taking antifolate antimalarial drugs in endemic areas, highlighting the public health relevance of this metabolic process. Recent proteomic investigations have further connected folate-related metabolic proteins to complex clinical phenotypes such as sepsis-associated sarcopenia, suggesting that this pathway may contribute to muscle wasting during critical illness. Understanding GO:0006760 therefore requires integrating enzymology, drug pharmacology, and disease biology, and CRISPR-based models provide powerful tools to test causal roles of individual pathway genes.

GO:0006760, folic acid-containing compound metabolic process, is defined as the chemical reactions and pathways involving a folic acid-containing compound, i.e. any of a group of heterocyclic compounds based on the pteroic acid skeleton conjugated with one or more L-glutamic acid or L-glutamate units. In practical terms, this term encompasses the synthesis, interconversion, polyglutamation, and utilization of folate species such as tetrahydrofolate and its one-carbon derivatives. It also includes the metabolic processing of antifolate drugs that mimic or compete with natural folates, because such compounds are chemically related to folic acid-containing molecules.

GO:0006760 is important because folate-dependent one-carbon metabolism is required for the biosynthesis of nucleotides and for amino acid interconversion, processes that are indispensable for cell proliferation and genome maintenance. The pathway is also a major pharmacological target: antifolate drugs used in cancer and infectious disease act by interfering with folate metabolism, and cellular folate status can determine whether such drugs are retained intracellularly through polyglutamation. In addition, folate supplementation has been studied in the context of malaria among people taking antifolate antimalarial drugs, underscoring the public health importance of this metabolic process. Emerging proteomic evidence linking folate-related proteins to sepsis-associated sarcopenia further suggests that this pathway may influence outcomes in critical illness.

The genes and proteins below are representative components and interacting factors of folate-dependent one-carbon metabolism and antifolate drug processing, based on published literature on GO:0006760.

Folate metabolism is regulated at multiple levels, including substrate availability, enzyme expression, and feedback through one-carbon flux. Cellular folate status directly influences the polyglutamation and retention of antifolate drugs, which can alter drug sensitivity and resistance. In clinical settings, folate supplementation can modify the pharmacology of antifolate antimalarial drugs, indicating that external folate intake is a regulatory input for this pathway. Proteomic evidence from sepsis-associated sarcopenia suggests that systemic inflammatory states may also be associated with altered abundance of folate-related proteins, although the regulatory mechanisms remain to be fully defined.

Folic acid supplementation has been evaluated for its effects on malaria susceptibility and severity among people taking antifolate antimalarial drugs in endemic areas. This interaction is clinically important because folate status can influence the efficacy of antifolate drugs used against malaria. The Cochrane review evidence highlights the need to balance folate supplementation with antimalarial treatment strategies.

Cellular folates can prevent polyglutamation of 5,10-dideazatetrahydrofolate, providing a novel mechanism of resistance to folate antimetabolites. This finding has implications for understanding why some tumors or cells respond poorly to antifolate chemotherapy. It also suggests that modulating folate status could be a strategy to overcome resistance.

Proteome sequencing in sepsis patients has identified folate-related metabolic proteins among the pathways potentially contributing to sarcopenia. This suggests that altered folate metabolism may be part of the complex pathophysiology of muscle wasting in critical illness. Further studies are needed to determine whether these changes are causal or compensatory.

Liquid chromatography-mass spectrometry can quantify folate species and their polyglutamated forms in cells and tissues. Such profiling is essential to determine how genetic perturbations alter the folate pool. It can also measure the metabolism of antifolate drugs such as 5,10-dideazatetrahydrofolate.

Genome-wide CRISPR knockout screens can identify genes that modify sensitivity to antifolates or that are required for folate metabolism. These screens are powerful for discovering new regulators of GO:0006760. Follow-up validation with individual knockouts confirms causal roles.

Proteome sequencing has been used to identify folate-related proteins in clinical samples such as sepsis patients with sarcopenia. Transcriptomic analysis can reveal changes in expression of folate pathway genes under different conditions. Integrating these datasets helps link GO:0006760 to disease phenotypes.

Cell viability assays with antifolate drugs can measure how genetic alterations in folate metabolism affect drug response. These assays are used to test resistance mechanisms involving polyglutamation. They can also be adapted to study antifolate antimalarial drugs in relevant models.

Researchers studying folic acid-containing compound metabolic process-related genes often need to determine whether a candidate gene is causally involved in folate-dependent phenotypes such as drug resistance, proliferation, or metabolic flux. EDITGENE provides CRISPR-based cell model services that enable precise genetic perturbations to answer these questions.

GO:0006760 folic acid-containing compound metabolic process is a fundamental biological process that supports one-carbon transfer reactions essential for nucleotide synthesis, methylation, and cell proliferation. Its clinical relevance spans antifolate drug resistance in cancer, malaria treatment interactions, and emerging links to critical illness such as sepsis-associated sarcopenia. CRISPR-based cell models offer a robust approach to dissect the causal roles of individual folate pathway genes, and EDITGENE provides comprehensive services to accelerate this research.