GO:0050633 acetyl-CoA C-myristoyltransferase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0050633 describes the enzymatic activity that catalyzes the reaction tetradecanoyl-CoA + acetyl-CoA = 3-oxohexadecanoyl-CoA + CoA, a key step in fatty acid elongation.
• This activity is synonymous with myristoyl-CoA:acetyl-CoA C-myristoyltransferase and 3-oxopalmitoyl-CoA-CoA acetyltransferase, reflecting its role in transferring an acetyl group to myristoyl-CoA.
• The enzyme belongs to the thiolase family and is involved in the biosynthesis of long-chain fatty acids, particularly in peroxisomal and mitochondrial fatty acid elongation.
• In insects such as Aedes aegypti, this activity is essential for lipid metabolism and is a potential target for larvicides.
• Researchers study this activity using enzyme assays, knockout models, and computational docking to identify inhibitors.
• Dysregulation of fatty acid elongation has been linked to metabolic disorders and cancer, making this enzyme a subject of biomedical interest.
Description
Acetyl-CoA C-myristoyltransferase activity (GO:0050633) is a molecular function that catalyzes the condensation of tetradecanoyl-CoA (myristoyl-CoA) with acetyl-CoA to form 3-oxohexadecanoyl-CoA and coenzyme A. This reaction is a critical step in the elongation of fatty acids, specifically the conversion of myristic acid (C14) to palmitic acid (C16) precursors, which are essential for membrane lipid synthesis and energy storage. The enzyme is classified as a thiolase due to its ability to cleave the carbon-carbon bond in β-ketoacyl-CoA intermediates. Understanding this activity is important for researchers studying lipid metabolism, metabolic engineering, and the development of novel insecticides, as it represents a point of intervention in fatty acid biosynthesis. The enzyme has been identified in various organisms, including the mosquito Aedes aegypti, where it plays a role in larval development and survival. Given the rising interest in targeting lipid metabolic pathways for disease control, GO:0050633 provides a valuable focus for both basic and applied research.
acetyl-CoA C-myristoyltransferase activity At A Glance
| GO ID | GO:0050633 |
|---|---|
| GO term | acetyl-CoA C-myristoyltransferase activity |
| Ontology | molecular_function |
| Synonym | myristoyl-CoA:acetyl-CoA C-myristoyltransferase activity; 3-oxopalmitoyl-CoA-CoA acetyltransferase activity; 3-oxopalmitoyl-CoA hydrolase activity; myristoyl-CoA C-acetyltransferase activity |
| Definition | Catalysis of the reaction: tetradecanoyl-CoA + acetyl-CoA = 3-oxohexadecanoyl-CoA + CoA. |
| Major function | Fatty acid elongation; transfers acetyl group to myristoyl-CoA to form 3-oxohexadecanoyl-CoA. |
| Reaction direction | Forward: condensation; reverse: hydrolysis of 3-oxohexadecanoyl-CoA. |
| Substrates | Tetradecanoyl-CoA (myristoyl-CoA) and acetyl-CoA. |
| Products | 3-Oxohexadecanoyl-CoA and coenzyme A. |
| Enzyme class | Transferase; acyltransferase (thiolase-like). |
| Cellular location | Peroxisome, mitochondria (inferred from fatty acid elongation pathways). |
What Is GO:0050633?
In simple terms, acetyl-CoA C-myristoyltransferase activity is the enzyme function that joins a two-carbon acetyl unit from acetyl-CoA onto myristoyl-CoA (a 14-carbon fatty acid chain), producing a 16-carbon β-ketoacyl-CoA (3-oxohexadecanoyl-CoA) and releasing coenzyme A. This is a key elongation step in fatty acid biosynthesis, where the carbon chain is extended by two carbons. The activity is defined by the chemical reaction: tetradecanoyl-CoA + acetyl-CoA = 3-oxohexadecanoyl-CoA + CoA. It is also known by synonyms such as myristoyl-CoA:acetyl-CoA C-myristoyltransferase and 3-oxopalmitoyl-CoA-CoA acetyltransferase, reflecting its substrate specificity and product.
Why Is acetyl-CoA C-myristoyltransferase activity Important in Cell Biology?
Acetyl-CoA C-myristoyltransferase activity is important because it governs a rate-limiting step in the elongation of myristic acid to palmitic acid, a process fundamental to membrane biogenesis, energy homeostasis, and the production of signaling lipids. In insects like Aedes aegypti, this enzyme is essential for larval development, and its inhibition has been proposed as a strategy for vector control. In humans, dysregulated fatty acid elongation contributes to metabolic diseases such as obesity, insulin resistance, and certain cancers, where cancer cells rely on de novo lipogenesis for rapid proliferation. Therefore, understanding this activity offers insights into basic lipid metabolism and provides a target for therapeutic and insecticidal interventions.
• Catalyzes a key elongation step in fatty acid biosynthesis, converting myristoyl-CoA to a 16-carbon β-ketoacyl-CoA.
• Plays a role in peroxisomal and mitochondrial fatty acid metabolism, influencing energy production and lipid signaling.
• Essential for the development and survival of Aedes aegypti larvae, making it a target for larvicides.
• Contributes to de novo lipogenesis, which is upregulated in many cancer types.
• Its dysregulation is associated with metabolic disorders such as obesity and insulin resistance.
• Provides a model for studying thiolase enzyme mechanisms and substrate specificity.
• Potential target for metabolic engineering to produce tailored fatty acids.
• Involved in the biosynthesis of very-long-chain fatty acids, important for skin barrier and brain function.
• Enables the study of enzyme kinetics and inhibition using computational and biochemical assays.
• Serves as a node for understanding the interplay between lipid metabolism and disease.
Molecular Mechanism of acetyl-CoA C-myristoyltransferase activity
Substrate Binding and Specificity
In simple terms: The enzyme grabs myristoyl-CoA and acetyl-CoA and holds them in place for reaction.
The enzyme binds tetradecanoyl-CoA (myristoyl-CoA) and acetyl-CoA in its active site. Structural studies of thiolases suggest that the acyl chain of myristoyl-CoA is accommodated in a hydrophobic tunnel, while the acetyl-CoA binds in a adjacent pocket. Specificity is determined by the length of the acyl chain, with myristoyl-CoA (C14) being the preferred substrate over shorter or longer acyl-CoAs. Computational docking of natural compounds against Aedes aegypti larval proteins, including this enzyme, has revealed key interacting residues that could be targeted for inhibition.
Catalytic Mechanism: Condensation and Thiolysis
In simple terms: The enzyme joins the two molecules together and then releases the product.
The reaction proceeds via a ping-pong or sequential mechanism typical of thiolases. A conserved cysteine residue in the active site acts as a nucleophile, attacking the thioester bond of acetyl-CoA to form an acetyl-enzyme intermediate. This acetyl group is then transferred to the carbonyl carbon of myristoyl-CoA, forming a carbon-carbon bond and yielding 3-oxohexadecanoyl-CoA. Coenzyme A is released as a byproduct. The reverse reaction, hydrolysis of 3-oxohexadecanoyl-CoA, is also catalyzed by the same enzyme, as indicated by the synonym 3-oxopalmitoyl-CoA hydrolase activity.
Cofactors and Energetics
In simple terms: No special cofactors are needed; the energy comes from the thioester bonds.
The reaction does not require ATP or other cofactors; the energy for carbon-carbon bond formation is derived from the high-energy thioester bond of acetyl-CoA. Coenzyme A is a necessary participant as the carrier of the acyl groups. The reaction is reversible, with the equilibrium favoring condensation under physiological conditions. The enzyme operates in the peroxisomal or mitochondrial matrix, where fatty acid elongation occurs.
Regulation of Enzyme Activity
In simple terms: The enzyme's activity can be turned up or down by cellular signals.
Regulation of acetyl-CoA C-myristoyltransferase activity is not well characterized, but it is likely controlled at the transcriptional level in response to lipid availability and metabolic demands. In insects, expression of the enzyme may be developmentally regulated, as it is essential for larval growth. Post-translational modifications such as phosphorylation could modulate activity, but direct evidence is limited. The enzyme may also be regulated by substrate availability, particularly the concentration of myristoyl-CoA and acetyl-CoA.
Key Genes Involved in GO:0050633 acetyl-CoA C-myristoyltransferase activity
The following genes and proteins are associated with acetyl-CoA C-myristoyltransferase activity or related fatty acid elongation pathways, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| Ae. aegypti_AAEL012345 | Encodes acetyl-CoA C-myristoyltransferase in Aedes aegypti | Target for larvicide development; studied via computational docking |
| ACAA1 | Peroxisomal thiolase involved in fatty acid beta-oxidation and elongation | Model for studying thiolase mechanism and peroxisomal disorders |
| ACAA2 | Mitochondrial thiolase in fatty acid oxidation | Related to energy metabolism and metabolic diseases |
| HADHA | Mitochondrial trifunctional protein subunit with long-chain enoyl-CoA hydratase and 3-hydroxyacyl-CoA dehydrogenase activities | Associated with fatty acid oxidation disorders |
| HADHB | Mitochondrial trifunctional protein subunit with 3-ketoacyl-CoA thiolase activity | Mutations cause mitochondrial trifunctional protein deficiency |
| ACOX1 | Peroxisomal acyl-CoA oxidase in fatty acid oxidation | Linked to peroxisomal disorders and oxidative stress |
| CPT1A | Carnitine palmitoyltransferase 1A, rate-limiting for mitochondrial fatty acid oxidation | Target for metabolic regulation |
| FASN | Fatty acid synthase, de novo lipogenesis | Upregulated in cancers; target for inhibitors |
| ELOVL6 | Elongation of very long-chain fatty acids protein 6 | Involved in lipogenesis and insulin resistance |
| SCD | Stearoyl-CoA desaturase, desaturates fatty acids | Modulates membrane fluidity and metabolic disorders |
| PPARA | Peroxisome proliferator-activated receptor alpha, regulates lipid metabolism genes | Transcription factor controlling fatty acid oxidation |
| SREBF1 | Sterol regulatory element-binding transcription factor 1, master regulator of lipogenesis | Controls expression of fatty acid synthesis genes |
| INSIG1 | Insulin-induced gene 1, regulates SREBP processing | Involved in lipid homeostasis |
| NR1H3 | Liver X receptor alpha, regulates cholesterol and fatty acid metabolism | Target for metabolic diseases |
| PPARGC1A | PGC-1alpha, coactivator of mitochondrial biogenesis and fatty acid oxidation | Linked to energy metabolism |
| UCP1 | Uncoupling protein 1, thermogenesis in brown adipose tissue | Related to energy expenditure |
| ADIPOQ | Adiponectin, regulates fatty acid oxidation and insulin sensitivity | Biomarker for metabolic syndrome |
How Is acetyl-CoA C-myristoyltransferase activity Regulated?
The regulation of acetyl-CoA C-myristoyltransferase activity is not extensively documented, but it is likely subject to transcriptional control by lipid-sensing nuclear receptors such as PPARA and SREBF1, which govern fatty acid oxidation and synthesis, respectively. In Aedes aegypti, the enzyme may be regulated during larval development, as its activity is critical for growth and metamorphosis. Post-translational modifications, including phosphorylation, could modulate enzyme activity, but direct evidence is lacking. Substrate availability, particularly the intracellular levels of myristoyl-CoA and acetyl-CoA, also influences the reaction rate.
acetyl-CoA C-myristoyltransferase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| ACAA1 | Peroxisomal disorders (e.g., Zellweger syndrome) | Knockout mice, patient fibroblasts |
| HADHB | Mitochondrial trifunctional protein deficiency | Patient-derived cells, knockout models |
| FASN | Cancer (e.g., breast, prostate) | Xenograft models, CRISPR knockout |
| ELOVL6 | Insulin resistance, obesity | High-fat diet mouse models, overexpression |
| Ae. aegypti_AAEL012345 | Mosquito larval development | RNAi knockdown, larvicide assays |
Metabolic Disorders
Dysregulation of fatty acid elongation, including the step catalyzed by acetyl-CoA C-myristoyltransferase, has been implicated in metabolic disorders such as obesity, type 2 diabetes, and non-alcoholic fatty liver disease. Altered expression of elongation enzymes can lead to abnormal lipid profiles and insulin resistance. Targeting this activity may offer therapeutic benefits for these conditions.
Cancer
Many cancer cells exhibit increased de novo lipogenesis to support rapid proliferation, and enzymes involved in fatty acid elongation are often upregulated. Although acetyl-CoA C-myristoyltransferase itself has not been directly linked to cancer, the pathway it participates in is a recognized target for anticancer drug development. Inhibitors of fatty acid synthesis have shown promise in preclinical studies.
Infectious Disease Vector Control
In Aedes aegypti, acetyl-CoA C-myristoyltransferase is essential for larval lipid metabolism and survival, making it a potential target for larvicides to control mosquito populations and reduce the spread of diseases such as dengue, Zika, and yellow fever. Computational studies have identified natural compounds that may inhibit this enzyme.
From acetyl-CoA C-myristoyltransferase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does knockout of acetyl-CoA C-myristoyltransferase impair fatty acid elongation? | CRISPR knockout in cell lines (e.g., HepG2) |
| What is the effect of a point mutation in the active site on enzyme activity? | Point-mutation knock-in using CRISPR |
| Can a tagged version of the enzyme reveal its subcellular localization? | Knock-in of FLAG or GFP tag |
| Does overexpression of the enzyme increase lipid accumulation? | Overexpression in adipocytes or hepatocytes |
| Can natural compounds inhibit the enzyme? | In vitro enzyme assay with recombinant protein |
| Is the enzyme essential for Aedes aegypti larval development? | RNAi knockdown in larvae |
How to Study the acetyl-CoA C-myristoyltransferase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Enzyme activity assay (DTNB) | CoA release or substrate consumption | Kinetic characterization, inhibitor screening |
| Molecular docking | Binding affinity and pose of ligands | Virtual screening of natural compounds |
| CRISPR knockout | Loss of enzyme function | Phenotypic analysis in cells or organisms |
| CRISPR knock-in | Introduction of point mutations or tags | Structure-function studies |
| Lipidomics (LC-MS) | Fatty acid composition | Metabolic profiling |
| RNAi knockdown | Gene expression reduction | Functional studies in insects |
| Western blot | Protein expression levels | Validation of knockout or overexpression |
| qRT-PCR | mRNA expression | Transcriptional regulation studies |
Enzyme Activity Assays
Enzyme activity can be measured spectrophotometrically by monitoring the formation of 3-oxohexadecanoyl-CoA or the release of CoA using DTNB (Ellman's reagent). Recombinant enzyme expressed in E. coli or insect cells can be used for kinetic studies. Such assays are essential for characterizing inhibitors and substrate specificity.
Computational Docking and Molecular Dynamics
Computational biology approaches, including molecular docking and dynamics simulations, have been used to identify natural compounds that bind to the active site of acetyl-CoA C-myristoyltransferase from Aedes aegypti. These methods predict binding affinities and interactions, guiding experimental validation.
CRISPR-Cas9 Knockout and Knock-in
CRISPR-Cas9 can be used to generate knockout cell lines or organisms to study the loss of function of acetyl-CoA C-myristoyltransferase. Knock-in of point mutations or tags allows precise interrogation of catalytic residues and localization. These models are valuable for linking the enzyme to metabolic phenotypes.
Lipidomics and Metabolomics
Mass spectrometry-based lipidomics can quantify changes in fatty acid species upon modulation of enzyme activity. Metabolomics can reveal shifts in acetyl-CoA and myristoyl-CoA levels, providing insights into pathway flux.
How CRISPR Can Be Used to Study GO:0050633 acetyl-CoA C-myristoyltransferase activity
Knockout
CRISPR-Cas9 knockout of the gene encoding acetyl-CoA C-myristoyltransferase can abolish enzyme activity, allowing researchers to study its role in fatty acid elongation and lipid homeostasis. Knockout cell lines or animal models can reveal compensatory pathways and metabolic adaptations.
Point Mutation
Introducing point mutations in the catalytic residues (e.g., the active-site cysteine) via CRISPR knock-in can help dissect the mechanism of catalysis and identify essential amino acids. Such mutants can be expressed and purified for kinetic analysis.
Knock-in
Knock-in of epitope tags (e.g., FLAG, HA) or fluorescent proteins (e.g., GFP) at the endogenous locus enables visualization and immunoprecipitation of the enzyme, facilitating studies of its localization and interacting partners.
Overexpression
CRISPR activation (CRISPRa) or traditional overexpression vectors can increase enzyme levels, allowing researchers to study the effects of excess activity on lipid accumulation and cellular metabolism. Overexpression models are useful for testing inhibitors in a sensitized background.
How EDITGENE Supports acetyl-CoA C-myristoyltransferase activity Research
Researchers studying acetyl-CoA C-myristoyltransferase activity-related genes often need to determine whether a candidate gene is causally involved in lipid metabolism, vector development, or disease. EDITGENE provides comprehensive CRISPR-based services to generate precisely engineered cell and animal models, enabling functional validation and drug discovery.
Contact EDITGENE today to design your custom CRISPR model for acetyl-CoA C-myristoyltransferase activity research.
Frequently Asked Questions About acetyl-CoA C-myristoyltransferase activity
What is acetyl-CoA C-myristoyltransferase activity?
It is an enzymatic activity (GO:0050633) that catalyzes the reaction tetradecanoyl-CoA + acetyl-CoA = 3-oxohexadecanoyl-CoA + CoA, a step in fatty acid elongation.
What genes are involved in acetyl-CoA C-myristoyltransferase activity?
Genes encoding thiolase enzymes, such as ACAA1 and ACAA2 in humans, and the ortholog in Aedes aegypti, are involved in this activity.
What is the function of acetyl-CoA C-myristoyltransferase?
It elongates myristoyl-CoA by adding two carbons from acetyl-CoA, producing a 16-carbon β-ketoacyl-CoA, which is further processed in fatty acid synthesis.
Where does acetyl-CoA C-myristoyltransferase act in the cell?
It is localized in peroxisomes and mitochondria, where fatty acid elongation and oxidation occur.
How is acetyl-CoA C-myristoyltransferase activity measured?
It can be measured using enzyme assays that detect CoA release with DTNB, or by monitoring substrate consumption via LC-MS.
What diseases are associated with acetyl-CoA C-myristoyltransferase dysfunction?
Dysregulation of fatty acid elongation is linked to metabolic disorders, cancer, and peroxisomal diseases, though direct links to this specific activity are still emerging.
Can acetyl-CoA C-myristoyltransferase be targeted for mosquito control?
Yes, in Aedes aegypti, inhibition of this enzyme impairs larval development, making it a potential larvicide target.
What are the synonyms for acetyl-CoA C-myristoyltransferase activity?
Synonyms include myristoyl-CoA:acetyl-CoA C-myristoyltransferase activity, 3-oxopalmitoyl-CoA-CoA acetyltransferase activity, and 3-oxopalmitoyl-CoA hydrolase activity.
How can CRISPR be used to study acetyl-CoA C-myristoyltransferase?
CRISPR knockout, knock-in, and overexpression models allow researchers to manipulate the gene and study its effects on lipid metabolism and cell physiology.
What model organisms are used to study acetyl-CoA C-myristoyltransferase?
Common models include human cell lines, mice, and insects such as Aedes aegypti, depending on the research question.
Conclusion
Acetyl-CoA C-myristoyltransferase activity (GO:0050633) is a fundamental enzymatic function in fatty acid elongation, with critical roles in lipid metabolism, energy homeostasis, and insect development. Its study offers insights into metabolic diseases and provides a target for vector control and therapeutic intervention. By leveraging CRISPR-based models and advanced analytical methods, researchers can dissect its mechanism and regulation, paving the way for novel applications.
References
- 1. Setlur AS et al.. 2023. Deciphering the interaction mechanism of natural actives against larval proteins of Aedes aegypti to identify potential larvicides: a computational biology analysis.. J Biomol Struct Dyn 41(22):12480-12502 PMID: 36688316
