GO:0016628 oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0016628 describes a molecular function: catalysis of a redox reaction in which a CH-CH group donates hydrogen/electrons and NAD+ or NADP+ is the acceptor.
• This activity is central to mitochondrial and cytosolic NAD(P)(H) homeostasis, influencing proline biosynthesis, folate-dependent nucleotide synthesis, and tumour growth [1,3,5].
• Key enzymes include NAD kinase (NADK), which phosphorylates NAD+ to NADP+, and downstream NADP(H)-dependent reductases/dehydrogenases [2,4,7].
• NADK and NADP(H) balance are implicated in cancer, metabolic reprogramming, and plant photosynthesis, making this GO term a target for therapeutic and agricultural research [3,5,7,8].
• CRISPR knockout, point-mutation, knock-in, and overexpression models enable causal testing of GO:0016628-related genes in disease and metabolism [1,3,5].
• EDITGENE provides end-to-end CRISPR cell model and library screening services to study oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor.
Description
GO:0016628, oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor, is a molecular function ontology term that defines a specific class of redox enzymes. These enzymes catalyse oxidation-reduction reactions where a carbon-carbon double bond (CH-CH) serves as the hydrogen or electron donor, and NAD+ or NADP+ acts as the electron acceptor. This activity is fundamental to cellular metabolism, connecting NAD(P)(H) pools to biosynthetic pathways such as proline synthesis and nucleotide production [1,5]. Researchers study GO:0016628 to understand how cells maintain redox balance, how metabolic flux is directed, and how dysregulation contributes to diseases including cancer [3,7]. The term is also critical in plant biology, where NADP(H) balance regulates photosynthesis and chloroplast development [6,8]. Because NAD kinase (NADK) generates NADP+, the substrate for many GO:0016628 enzymes, its regulation directly impacts this activity [2,4]. This article synthesises authoritative QuickGO data and verified PubMed literature to provide a research-grade overview of GO:0016628, its genes, mechanisms, disease links, and experimental methods.
oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor At A Glance
| GO ID | GO:0016628 |
|---|---|
| GO term | oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor |
| Ontology | molecular_function |
| Synonym | None |
| Definition | Catalysis of an oxidation-reduction (redox) reaction in which a CH-CH group acts as a hydrogen or electron donor and reduces NAD or NADP. |
| Major function | Redox catalysis using NAD+ or NADP+ as electron acceptor |
| Related cofactors | NAD+, NADP+, NADH, NADPH |
| Representative enzymes | NAD kinase (NADK), NADP-dependent oxidoreductases |
| Disease relevance | Cancer, metabolic disorders, plant stress responses |
What Is GO:0016628?
GO:0016628 is defined by QuickGO as: Catalysis of an oxidation-reduction (redox) reaction in which a CH-CH group acts as a hydrogen or electron donor and reduces NAD or NADP. In simpler terms, it is a molecular function where an enzyme removes hydrogen from a carbon-carbon double bond and transfers electrons to NAD+ or NADP+, converting them to NADH or NADPH. This activity is essential for maintaining cellular redox homeostasis and supporting biosynthetic reactions that require reducing power [1,5].
Why Is oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor Important in Cell Biology?
GO:0016628 is important because it governs a core redox mechanism that links NAD(P)(H) metabolism to essential biosynthetic and bioenergetic pathways. Mitochondrial NADP(H) generation, driven by enzymes such as NADK, is required for proline biosynthesis and tumour growth [1,3]. Cytosolic NADK is conditionally essential for folate-dependent nucleotide synthesis, highlighting its role in proliferation. In plants, NADP+ supply adjusts photosystem I synthesis, making this activity vital for photosynthesis. Dysregulation of NAD(P)(H) balance is implicated in cancer, where NADK is a therapeutic target. Thus, understanding GO:0016628 provides mechanistic insight into metabolic reprogramming and identifies potential drug targets.
• Supports mitochondrial proline biosynthesis, which is essential for cancer cell growth.
• Maintains NADP(H) pools required for antioxidant defence and reductive biosynthesis [2,4].
• Enables folate-dependent nucleotide synthesis in proliferating cells.
• Regulates photosystem I synthesis and chloroplast development in plants.
• Is a therapeutic target in cancer due to NADK overexpression.
• Connects to tumour growth via mitochondrial ubiquinol oxidation.
• Influences NAD(P)(H) balance through chloroplast NADP(H) phosphatases.
• Provides a mechanistic basis for metabolic engineering and drug discovery [5,7].
Molecular Mechanism of oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor
Substrate recognition and CH-CH donor binding
In simple terms: The enzyme first grabs the molecule that has a carbon-carbon double bond.
Enzymes with GO:0016628 activity bind substrates containing a CH-CH group, positioning them for hydride transfer. This step is exemplified by NADP-dependent oxidoreductases that act on unsaturated carbon bonds, as seen in proline biosynthesis where mitochondrial NADP(H) is consumed. The specificity for CH-CH donors distinguishes this class from other oxidoreductases.
Hydride transfer to NAD+ or NADP+
In simple terms: The enzyme moves hydrogen from the substrate to NAD+ or NADP+.
The catalytic core facilitates hydride transfer from the CH-CH group to the nicotinamide ring of NAD+ or NADP+, reducing it to NADH or NADPH. This mechanism is shared by NADK-dependent pathways that generate NADP(H) for reductive biosynthesis [2,4]. Structural studies of human NADK reveal regulatory domains that control NADP+ production, indirectly influencing this activity.
Cofactor regeneration and NAD(P)(H) balance
In simple terms: The cell recycles NAD+ and NADP+ to keep the reaction going.
NAD kinase (NADK) phosphorylates NAD+ to NADP+, supplying the acceptor for GO:0016628 enzymes [2,7]. Cytosolic NADK is conditionally essential for folate-dependent nucleotide synthesis, linking cofactor supply to biosynthetic demand. In Arabidopsis, CCR4C acts as a chloroplast-localized NADP(H) phosphatase regulating NAD(P)(H) balance, affecting photosystem I synthesis [6,8].
Regulation by metabolic demand and disease state
In simple terms: The reaction speeds up or slows down based on what the cell needs.
NADK expression and activity are regulated by metabolic cues and oncogenic signals, making GO:0016628 activity responsive to cellular needs. Mitochondrial NADP(H) generation is essential for proline biosynthesis, and its disruption impairs tumour growth [1,3]. Thus, this activity is tightly coupled to proliferation and redox stress.
Key Genes Involved in GO:0016628 oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor
The following genes and proteins are experimentally linked to GO:0016628 or its cofactor supply, based on verified literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| NADK | Phosphorylates NAD+ to NADP+ | Central to NADP(H) supply for GO:0016628 enzymes; cancer target [2,7] |
| NADK2 | Mitochondrial NAD kinase | Essential for mitochondrial NADP(H) and proline biosynthesis |
| PYCR1 | Proline synthesis enzyme | Consumes NADPH; linked to mitochondrial NADP(H) |
| MTHFD2 | Folate-dependent enzyme | Requires NADP(H); cytosolic NADK supports nucleotide synthesis |
| CCR4C | Chloroplast NADP(H) phosphatase | Regulates NAD(P)(H) balance in Arabidopsis |
| NDUFS1 | Complex I subunit | Mitochondrial ubiquinol oxidation for tumour growth |
| SDHA | Succinate dehydrogenase | CH-CH oxidation in TCA cycle; NAD+ acceptor |
| ACADM | Acyl-CoA dehydrogenase | Fatty acid beta-oxidation; CH-CH donor to NAD+ |
| HADHA | Trifunctional enzyme | Fatty acid oxidation; NAD+ dependent |
| ALDH2 | Aldehyde dehydrogenase | NAD+ dependent oxidation; related redox balance |
| G6PD | Glucose-6-phosphate dehydrogenase | Generates NADPH; supports GO:0016628 reactions |
| IDH2 | Isocitrate dehydrogenase | Mitochondrial NADP+ dependent; redox homeostasis |
| ME1 | Malic enzyme | NADP+ dependent; links metabolism to NADPH |
| NNT | Nicotinamide nucleotide transhydrogenase | Maintains NADPH/NAD+ balance |
| NAPRT | Nicotinate phosphoribosyltransferase | NAD+ salvage; affects NADP+ pools |
| NMNAT1 | Nicotinamide mononucleotide adenylyltransferase | NAD+ biosynthesis; upstream of NADK |
How Is oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor Regulated?
GO:0016628 activity is regulated at multiple levels. NADK, which supplies NADP+, is controlled by transcriptional and post-translational mechanisms in response to metabolic demand [2,4]. Cytosolic NADK is conditionally essential for folate-dependent nucleotide synthesis, indicating regulation by one-carbon metabolism. In plants, CCR4C regulates NAD(P)(H) balance in chloroplasts, affecting photosystem I synthesis [6,8]. Mitochondrial NADP(H) generation is essential for proline biosynthesis and is coupled to tumour growth, suggesting regulation by oncogenic signalling [1,3]. NADK is a therapeutic target in cancer, and its inhibition alters redox balance.
oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| NADK | Cancer proliferation | Knockout and overexpression in cancer cell lines |
| NADK2 | Tumour growth and proline synthesis | Mitochondrial-targeted knockout |
| MTHFD2 | Folate-dependent nucleotide synthesis | Conditional knockout in proliferating cells |
| CCR4C | Plant NAD(P)(H) balance | Arabidopsis knockout and overexpression |
| NDUFS1 | Mitochondrial ubiquinol oxidation | Knockout in tumour models |
Cancer metabolism and tumour growth
GO:0016628-related enzymes support biosynthetic and redox demands of cancer cells. Mitochondrial NADP(H) generation is essential for proline biosynthesis, and its loss impairs tumour growth. Mitochondrial ubiquinol oxidation is necessary for tumour growth, linking this activity to bioenergetics. NADK is overexpressed in cancers and is a therapeutic target. Cytosolic NADK is conditionally essential for folate-dependent nucleotide synthesis, supporting proliferation.
Metabolic disorders and redox imbalance
Dysregulation of NAD(P)(H) balance contributes to metabolic stress. NADK deficiency or inhibition can disrupt NADP+ supply, affecting antioxidant defences and biosynthesis [2,4]. Inborn errors in proline synthesis, which depends on mitochondrial NADP(H), are linked to metabolic disease.
Plant stress and photosynthesis
In Arabidopsis, CCR4C regulates NAD(P)(H) balance, and NADP+ supply adjusts photosystem I synthesis [6,8]. These findings highlight the importance of GO:0016628 in plant growth and stress responses.
From oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does NADK loss impair tumour growth? | NADK knockout cancer cell lines and xenografts |
| Is mitochondrial NADP(H) required for proline synthesis? | NADK2 knockout cells with proline rescue |
| How does cytosolic NADK support nucleotide synthesis? | Conditional NADK knockout in folate-dependent cells |
| What is the role of CCR4C in chloroplast NADP(H) balance? | Arabidopsis ccr4c mutants |
| Does NADP+ supply regulate photosystem I? | Plant lines with altered NADK expression |
| Can point mutations in NADK alter activity? | CRISPR knock-in of catalytic mutants |
How to Study the oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA-seq | Transcriptional changes | Knockout vs wild-type cells |
| Metabolomics | NADP(H) and pathway metabolites | Proline and nucleotide synthesis [1,5] |
| Cryo-EM | Protein structure and cofactor binding | NADK regulation |
| Enzyme assay | Catalytic activity | Hydride transfer to NADP+ |
| CRISPR library screen | Gene essentiality | Identify synthetic lethal targets |
| NADP(H) sensor imaging | Real-time redox state | Live-cell metabolism |
| Chloroplast isolation | Photosystem I synthesis | Plant NADP+ supply |
Genomic and transcriptomic profiling
RNA-seq and CRISPR screens can identify genes required for GO:0016628 activity. Knockout of NADK or NADK2 followed by RNA-seq reveals transcriptional responses to redox stress [1,5]. Library screening can uncover synthetic lethal interactions.
Metabolomics and flux analysis
Mass spectrometry-based metabolomics measures NADP(H) and pathway intermediates such as proline and nucleotides. This is critical for linking GO:0016628 to metabolic flux [1,5].
Structural and biochemical assays
Cryo-EM and X-ray crystallography of NADK provide mechanistic insights into cofactor binding and regulation. Enzyme assays with purified proteins measure hydride transfer to NAD+ or NADP+.
Imaging and reporter systems
Genetically encoded NADP(H) sensors and fluorescent reporters allow real-time monitoring of redox state in live cells. These tools are used to study GO:0016628 in cancer and plant models [3,8].
How CRISPR Can Be Used to Study GO:0016628 oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor
Knockout
CRISPR knockout of NADK, NADK2, or MTHFD2 enables loss-of-function studies to test their role in GO:0016628-dependent pathways. For example, NADK2 knockout impairs mitochondrial NADP(H) and proline synthesis. Cytosolic NADK knockout reduces folate-dependent nucleotide synthesis.
Point Mutation
Point mutations in catalytic residues of NADK or downstream oxidoreductases can dissect mechanism. CRISPR knock-in of catalytic-dead mutants allows separation of enzymatic activity from scaffolding functions.
Knock-in
Knock-in of tagged or fluorescently labelled NADK enables localization and interaction studies. This is useful for tracking NADP(H) dynamics in live cells.
Overexpression
Overexpression of NADK or NADK2 increases NADP(H) supply and can drive proline synthesis or tumour growth. This models gain-of-function states observed in cancer.
How EDITGENE Supports oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor Research
Researchers studying oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor-related genes often need to determine whether a candidate gene is causally involved in redox metabolism, biosynthesis, or disease. EDITGENE provides validated CRISPR cell models and screening services to accelerate this discovery.
Contact EDITGENE today to design your custom CRISPR model for oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor research.
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| DHCR7 Knockout HEK293 Cell Line | EDJ-KQ1955 | Human | 1717 | Details Get a Quote |
| PTGR1 Knockout HEK293 Cell Line | EDJ-KQ2066 | Human | 22949 | Details Get a Quote |
| LBR Knockout HEK293 Cell Line | EDJ-KQ2233 | Human | 3930 | Details Get a Quote |
| DHCR24 Knockout HEK293 Cell Line | EDJ-KQ4442 | Human | 1718 | Details Get a Quote |
| PTGR2 Knockout HEK293 Cell Line | EDJ-KQ10442 | Human | 145482 | Details Get a Quote |
| BDH2 Knockout HEK293 Cell Line | EDJ-KQ12528 | Human | 56898 | Details Get a Quote |
| SRD5A3 Knockout HEK293 Cell Line | EDJ-KQ16792 | Human | 79644 | Details Get a Quote |
| LBR Knockout HeLa Cell Line | EDJ-KQ21215 | Human | 3930 | Details Get a Quote |
| DHCR24 Knockout A-549 Cell Line | EDJ-KQ26995 | Human | 1718 | Details Get a Quote |
| DHCR24 Knockout HCT 116 Cell Line | EDJ-KQ26996 | Human | 1718 | Details Get a Quote |
| DHCR24 Knockout HeLa Cell Line | EDJ-KQ26997 | Human | 1718 | Details Get a Quote |
| BDH2 Knockout A-549 Cell Line | EDJ-KQ41514 | Human | 56898 | Details Get a Quote |
| BDH2 Knockout HeLa Cell Line | EDJ-KQ41516 | Human | 56898 | Details Get a Quote |
| LBR Knockout A-549 Cell Line | EDJ-KQ22522 | Human | 3930 | Details Get a Quote |
| LBR Knockout HCT 116 Cell Line | EDJ-KQ22523 | Human | 3930 | Details Get a Quote |
Displaying Records 1 To 15 Of 32 Records
- 1
- 2
- Next Page »
Frequently Asked Questions About oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor
What is GO:0016628?
GO:0016628 is a molecular function term for oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor. It describes enzymes that catalyse redox reactions where a CH-CH group donates hydrogen and NAD+ or NADP+ is reduced.
What genes are involved in oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor?
Key genes include NADK, NADK2, PYCR1, MTHFD2, and CCR4C, which supply or utilise NADP(H) for this activity [1,2,5,6].
Why is NADK important for GO:0016628?
NADK phosphorylates NAD+ to NADP+, generating the electron acceptor required by GO:0016628 enzymes [2,7].
How is GO:0016628 linked to cancer?
Mitochondrial NADP(H) generation supports proline biosynthesis and tumour growth, and NADK is a therapeutic target in cancer [1,3,7].
What experimental models study GO:0016628?
CRISPR knockout, point mutation, knock-in, and overexpression cell lines, as well as Arabidopsis mutants for plant studies [1,5,6].
What is the role of NADP(H) in proline synthesis?
Mitochondrial NADP(H) is consumed by PYCR1 during proline synthesis, linking GO:0016628 to biosynthetic pathways.
How does cytosolic NADK affect nucleotide synthesis?
Cytosolic NADK is conditionally essential for folate-dependent nucleotide synthesis, providing NADPH for biosynthetic reactions.
What is CCR4C and how does it relate to GO:0016628?
CCR4C is a chloroplast-localized NADP(H) phosphatase that regulates NAD(P)(H) balance, influencing photosystem I synthesis.
Can CRISPR screens identify genes for GO:0016628?
Yes, CRISPR library screening can uncover genes required for NADP(H) homeostasis and redox balance.
What methods measure GO:0016628 activity?
Enzyme assays, metabolomics, cryo-EM, and NADP(H) sensor imaging are commonly used [2,3,4].
Conclusion
GO:0016628 defines a vital redox function that connects NAD(P)(H) metabolism to biosynthesis, antioxidant defence, and disease. Key enzymes such as NADK and NADK2 supply NADP+, while downstream oxidoreductases drive proline synthesis, nucleotide production, and photosynthesis [1,2,5,8]. Dysregulation is implicated in cancer and metabolic disorders, making this activity a promising therapeutic target [3,7]. CRISPR-based models and EDITGENE services empower researchers to dissect these mechanisms and translate findings into new interventions.
References
- 1. Zhu J et al.. 2021. Mitochondrial NADP(H) generation is essential for proline biosynthesis.. Science 372(6545):968-972 PMID: 33888598
- 2. McGuinness ET et al.. 1985. NAD+ kinase--a review.. Int J Biochem 17(1):1-11 PMID: 2987053
- 3. Martínez-Reyes I et al.. 2020. Mitochondrial ubiquinol oxidation is necessary for tumour growth.. Nature 585(7824):288-292 PMID: 32641834
- 4. Praharaj PP et al.. 2025. Cryo-EM structure and regulation of human NAD kinase.. Sci Adv 11(4):eads2664 PMID: 39854463
- 5. Flickinger KM et al.. 2025. Cytosolic NADK is conditionally essential for folate-dependent nucleotide synthesis.. Nat Metab 7(6):1150-1167 PMID: 40316835
- 6. Akashi K et al.. 2025. Identification of CCR4C as a chloroplast-localized NADP(H) phosphatase regulating NAD(P)(H) balance in Arabidopsis.. Proc Natl Acad Sci U S A 122(42):e2504605122 PMID: 41091769
- 7. Tedeschi PM et al.. 2016. NAD+ Kinase as a Therapeutic Target in Cancer.. Clin Cancer Res 22(21):5189-5195 PMID: 27582489
- 8. Ji D et al.. 2022. NADP+ supply adjusts the synthesis of photosystem I in Arabidopsis chloroplasts.. Plant Physiol 189(4):2128-2143 PMID: 35385122
