GO:0003841 1-acylglycerol-3-phosphate O-acyltransferase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0003841 describes the enzymatic activity that converts 1-acyl-sn-glycerol-3-phosphate (lysophosphatidic acid) into 1,2-diacyl-sn-glycerol-3-phosphate (phosphatidic acid) using acyl-CoA as the acyl donor.
• This activity is essential for the de novo biosynthesis of glycerophospholipids and triacylglycerols, and it is catalyzed by the AGPAT/GPAT family of enzymes [1,2].
• Mutations in AGPAT2 cause congenital generalized lipodystrophy, and reduced enzymatic activity is a key pathogenic mechanism.
• AGPAT11 is upregulated in breast and cervical cancers, suggesting a role in tumor lipid metabolism.
• Loss of AGPAT activity can disrupt mitochondrial function and lipid droplet homeostasis, as shown for Slc1 in bacteria.
• The enzyme is a potential therapeutic target for metabolic disorders, cancer, and ferroptosis-related diseases [3,5].
Description
1-acylglycerol-3-phosphate O-acyltransferase (AGPAT) activity, encoded by GO:0003841, is a central enzymatic step in glycerophospholipid biosynthesis. It catalyzes the acylation of lysophosphatidic acid (LPA) at the sn-2 position to form phosphatidic acid (PA), using acyl-CoA as the acyl donor. This reaction is critical for the production of all diacylglycerol-containing lipids, including phosphatidylcholine, phosphatidylethanolamine, and triacylglycerols. Researchers study this activity to understand lipid metabolism, membrane biogenesis, and energy storage, as well as its implications in metabolic diseases and cancer [1,2]. The AGPAT family comprises multiple isoforms with distinct tissue distributions and substrate specificities, and their dysregulation has been linked to severe human disorders such as congenital generalized lipodystrophy and Chanarin-Dorfman syndrome [1,5]. Understanding the molecular mechanism, regulation, and disease relevance of GO:0003841 is therefore essential for both basic biology and translational research.
1-acylglycerol-3-phosphate O-acyltransferase activity At A Glance
| GO ID | GO:0003841 |
|---|---|
| GO term | 1-acylglycerol-3-phosphate O-acyltransferase activity |
| Ontology | molecular_function |
| Synonym | lysophosphatidate acyltransferase activity; 1-acylglycerophosphate acyltransferase activity; 1-acyl-sn-glycerol-3-phosphate acyltransferase activity |
| Major function | Catalyzes the conversion of lysophosphatidic acid to phosphatidic acid using acyl-CoA |
| Reaction | acyl-CoA + 1-acyl-sn-glycerol-3-phosphate = CoA + 1,2-diacyl-sn-glycerol-3-phosphate |
| EC number | 2.3.1.51 |
| Pathway | Glycerophospholipid biosynthesis; triacylglycerol biosynthesis |
What Is GO:0003841?
GO:0003841 describes the catalytic activity of an enzyme that transfers an acyl group from acyl-CoA to the sn-2 position of 1-acyl-sn-glycerol-3-phosphate (lysophosphatidic acid), yielding CoA and 1,2-diacyl-sn-glycerol-3-phosphate (phosphatidic acid). This activity is also known as lysophosphatidate acyltransferase or 1-acylglycerophosphate acyltransferase.
Why Is 1-acylglycerol-3-phosphate O-acyltransferase activity Important in Cell Biology?
GO:0003841 is a critical node in lipid metabolism because it generates phosphatidic acid, a key intermediate for the synthesis of all glycerophospholipids and triacylglycerols. Dysregulation of this activity leads to severe metabolic disorders, including congenital generalized lipodystrophy and Chanarin-Dorfman syndrome, and is implicated in cancer progression and ferroptosis [1,2,3,5]. Understanding its mechanism and regulation offers opportunities for therapeutic intervention in metabolic diseases and cancer.
• Essential for the de novo synthesis of phosphatidic acid, a precursor for all diacylglycerol lipids.
• Mutations in AGPAT2 cause congenital generalized lipodystrophy, a severe metabolic disorder.
• AGPAT11 is upregulated in breast and cervical cancers, linking the enzyme to tumorigenesis.
• The activity is required for maintaining mitochondrial function and lipid droplet homeostasis.
• It plays a role in protecting against ferroptosis by maintaining docosahexaenoate-containing phospholipids.
• Chanarin-Dorfman syndrome, a neutral lipid storage disease, involves dysregulation of lipid metabolism related to this activity.
• AGPAT isoforms are potential drug targets for obesity, diabetes, and cancer [2,6].
• The enzyme is conserved across species, from bacteria to humans, making it a model for studying lipid metabolism evolution [4,8].
What Happens During 1-acylglycerol-3-phosphate O-acyltransferase activity?
Substrate Recognition and Binding
In simple terms: The enzyme grabs its two starting materials: a lysophosphatidic acid molecule and an acyl-CoA molecule.
The enzyme binds 1-acyl-sn-glycerol-3-phosphate (lysophosphatidic acid) and an acyl-CoA thioester. The acyl-CoA provides the fatty acid that will be attached to the glycerol backbone. Isoform-specific differences in substrate specificity have been observed; for example, AGPAT2 and AGPAT11 show distinct preferences for different acyl-CoA species [1,2].
Catalytic Acylation
In simple terms: The enzyme transfers the fatty acid from acyl-CoA onto the lysophosphatidic acid, forming phosphatidic acid.
The catalytic mechanism involves the nucleophilic attack of the sn-2 hydroxyl of lysophosphatidic acid on the thioester carbonyl of acyl-CoA, resulting in the formation of a new ester bond and release of CoA. This reaction is characteristic of the 1-acylglycerol-3-phosphate O-acyltransferase family, which includes AGPAT1-11 in humans [1,6].
Product Release and Membrane Integration
In simple terms: The newly made phosphatidic acid is released and becomes part of the cell membrane or is used for energy storage.
Phosphatidic acid is a central intermediate that can be dephosphorylated to diacylglycerol for triacylglycerol synthesis or converted to CDP-diacylglycerol for phospholipid synthesis. The enzyme is typically localized to the endoplasmic reticulum membrane, where it facilitates the channeling of newly synthesized lipids [1,4].
Role in Lipid Droplet and Mitochondrial Homeostasis
In simple terms: This enzyme helps keep fat storage and energy production in balance.
Studies in bacteria and eukaryotes show that loss of 1-acylglycerol-3-phosphate O-acyltransferase activity leads to altered lipid droplet formation and mitochondrial dysfunction. For instance, Slc1 in bacteria is required to regulate mitochondria and lipid droplets. In humans, AGPAT2 mutations disrupt lipid homeostasis and cause lipodystrophy.
Key Genes Involved in GO:0003841 1-acylglycerol-3-phosphate O-acyltransferase activity
The following genes encode enzymes with 1-acylglycerol-3-phosphate O-acyltransferase activity or are directly related to its function.
| Gene | Major Role | Research Relevance |
|---|---|---|
| AGPAT1 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 1 | Ubiquitously expressed; involved in basic phospholipid synthesis |
| AGPAT2 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 2 | Mutations cause congenital generalized lipodystrophy; key for adipose tissue development |
| AGPAT3 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 3 | May have roles in brain and testis lipid metabolism |
| AGPAT4 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 4 | Associated with mitochondrial function and cancer |
| AGPAT5 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 5 | Involved in endoplasmic reticulum lipid synthesis |
| AGPAT6 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 6 | Also known as GPAT4; contributes to triacylglycerol synthesis |
| AGPAT7 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 7 | May play a role in skin barrier function |
| AGPAT8 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 8 | Also known as LYCAT; involved in cardiolipin remodeling |
| AGPAT9 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 9 | Also known as GPAT3; linked to obesity and insulin resistance |
| AGPAT10 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 10 | Also known as GPAT1; mitochondrial isoform |
| AGPAT11 | Encodes 1-acylglycerol-3-phosphate O-acyltransferase 11 | Upregulated in breast and cervical cancers |
| GPAT1 | Mitochondrial glycerol-3-phosphate acyltransferase | First step in glycerolipid synthesis; distinct from AGPAT |
| GPAT4 | Endoplasmic reticulum glycerol-3-phosphate acyltransferase | Overlaps with AGPAT6; involved in lipid storage |
| PNPLA3 | Patatin-like phospholipase domain-containing protein 3 | I148M variant interferes with hepatic triglyceride clearance |
| SLC1 | Bacterial 1-acylglycerol-3-phosphate acyltransferase | Regulates mitochondria and lipid droplets in bacteria |
| LPGAT1 | Lysophosphatidylglycerol acyltransferase 1 | Related acyltransferase with overlapping substrate specificity |
| MOGAT1 | Monoacylglycerol O-acyltransferase 1 | Uses diacylglycerol as substrate; related to AGPAT pathway |
| DGAT1 | Diacylglycerol O-acyltransferase 1 | Converts diacylglycerol to triacylglycerol; downstream of AGPAT |
How Is 1-acylglycerol-3-phosphate O-acyltransferase activity Regulated?
The activity of 1-acylglycerol-3-phosphate O-acyltransferase is regulated at multiple levels. Transcriptional regulation of AGPAT isoforms is tissue-specific and responsive to metabolic cues such as insulin and fasting. Post-translational modifications, including phosphorylation, may modulate enzyme activity. Additionally, the availability of substrates (lysophosphatidic acid and acyl-CoA) and the lipid environment influence enzymatic rate. In cancer, AGPAT11 upregulation suggests oncogenic transcriptional activation. The enzyme also interacts with other lipid metabolic pathways, and its activity can be affected by the cellular energy status and redox balance.
1-acylglycerol-3-phosphate O-acyltransferase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| AGPAT2 | Congenital generalized lipodystrophy | Knockout mice, patient-derived fibroblasts, point-mutation knock-in |
| AGPAT11 | Breast and cervical cancer | Overexpression in cancer cell lines, xenograft models |
| ABHD5 | Chanarin-Dorfman syndrome | Knockout or point-mutation in hepatocytes and keratinocytes |
| PNPLA3 | Hepatic triglyceride clearance, NAFLD | I148M knock-in mice, hepatocyte overexpression |
| SLC1 | Bacterial lipid droplet and mitochondrial regulation | Bacterial knockout and complementation |
Congenital Generalized Lipodystrophy
Mutations in AGPAT2 are the most common cause of congenital generalized lipodystrophy type 1, a severe disorder characterized by near-total absence of adipose tissue, insulin resistance, and hepatic steatosis. Enzymatic studies show that these mutations reduce or abolish 1-acylglycerol-3-phosphate O-acyltransferase activity, impairing adipocyte differentiation and lipid storage.
Cancer
AGPAT11 (also known as AGPAT11) is upregulated in breast and cervical cancers, and its enzymatic activity is elevated in cancer cell lines. This suggests that increased phosphatidic acid synthesis supports rapid membrane biogenesis and proliferation in tumor cells, making AGPAT11 a potential therapeutic target.
Chanarin-Dorfman Syndrome
Chanarin-Dorfman syndrome is a neutral lipid storage disease with ichthyosis, caused by mutations in ABHD5. Although the primary defect is in ABHD5, the disease involves dysregulation of lipid metabolism, including altered phosphatidic acid metabolism, which is linked to 1-acylglycerol-3-phosphate O-acyltransferase activity.
Ferroptosis and Neurodegeneration
Maintaining homeostasis of docosahexaenoate-containing phospholipids, which requires 1-acylglycerol-3-phosphate O-acyltransferase activity, protects against ferroptosis, a form of regulated cell death implicated in neurodegeneration. Thus, dysregulation of this activity may contribute to neuronal loss.
From 1-acylglycerol-3-phosphate O-acyltransferase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of AGPAT2 cause lipodystrophy? | AGPAT2 knockout mouse or patient iPSC-derived adipocytes |
| How does AGPAT11 contribute to cancer? | AGPAT11 overexpression in breast cancer cell lines and xenografts |
| What is the effect of AGPAT point mutations on enzyme activity? | Site-directed mutagenesis and knock-in cell lines |
| Can AGPAT activity be targeted to treat ferroptosis? | Knockout or overexpression of AGPAT in neuronal cell models |
| How does AGPAT regulate lipid droplets? | Tagged knock-in of AGPAT with fluorescent protein in HeLa cells |
| What is the role of AGPAT in mitochondrial function? | Knockout of Slc1 in bacteria and mitochondrial assays |
How to Study the 1-acylglycerol-3-phosphate O-acyltransferase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Enzymatic activity assay | Conversion of LPA to PA | Determining kinetic parameters and mutant effects |
| Lipidomics (LC-MS/MS) | Lipid species abundance | Profiling phosphatidic acid and related lipids |
| CRISPR knockout screen | Gene essentiality and synthetic lethality | Identifying regulators of AGPAT activity |
| Overexpression | Gain-of-function effects | Studying cancer cell proliferation and lipid metabolism |
| RNA-seq | Transcriptional changes | Assessing AGPAT isoform expression in tissues |
| Proteomics | Protein interactions and modifications | Identifying AGPAT binding partners |
| Fluorescence microscopy | Lipid droplet and mitochondrial morphology | Visualizing organelle dynamics |
| Site-directed mutagenesis | Enzyme activity of point mutants | Mapping catalytic residues and disease mutations |
Enzymatic Activity Assays
Direct measurement of 1-acylglycerol-3-phosphate O-acyltransferase activity using radiolabeled or fluorescent substrates is the gold standard. Cell lysates or purified enzyme are incubated with lysophosphatidic acid and acyl-CoA, and the formation of phosphatidic acid is quantified by thin-layer chromatography or mass spectrometry [1,2].
Lipidomics and Mass Spectrometry
Global lipid profiling by LC-MS/MS can reveal changes in phosphatidic acid and other glycerophospholipids upon modulation of AGPAT expression. This approach is useful for understanding the broader metabolic impact.
CRISPR-Based Genetic Screens
Genome-wide CRISPR knockout or activation screens can identify genes that regulate AGPAT activity or that are synthetically lethal with AGPAT loss. Such screens are powerful for discovering novel components of lipid metabolism.
Imaging of Lipid Droplets and Mitochondria
Fluorescence microscopy with lipid droplet dyes (e.g., BODIPY) and mitochondrial markers can visualize changes in organelle morphology upon AGPAT manipulation. This is particularly relevant for studying the role of AGPAT in lipid storage and mitochondrial function.
How CRISPR Can Be Used to Study GO:0003841 1-acylglycerol-3-phosphate O-acyltransferase activity
Knockout
CRISPR knockout of AGPAT genes in cell lines or animal models can abolish enzymatic activity, leading to defects in lipid synthesis and storage. For example, AGPAT2 knockout recapitulates lipodystrophy phenotypes in mice and cell models. Knockout of bacterial Slc1 impairs mitochondrial function and lipid droplet formation.
Point Mutation
Introducing disease-associated point mutations (e.g., in AGPAT2) via CRISPR base editing or homology-directed repair allows precise study of enzymatic activity and structural consequences. Such models have shown that specific mutations reduce catalytic efficiency.
Knock-in
Knock-in of tagged AGPAT (e.g., GFP or FLAG) enables live-cell imaging and proteomic analysis of the enzyme's localization and interactions. This is valuable for understanding its subcellular distribution and dynamics.
Overexpression
CRISPR activation (CRISPRa) or lentiviral overexpression of AGPAT isoforms can model the upregulation observed in cancers. Overexpression of AGPAT11 in breast cancer cells increases phosphatidic acid levels and promotes proliferation.
How EDITGENE Supports 1-acylglycerol-3-phosphate O-acyltransferase activity Research
Researchers studying 1-acylglycerol-3-phosphate O-acyltransferase activity-related genes often need to determine whether a candidate gene is causally involved in lipid metabolism, disease pathogenesis, or drug response. EDITGENE provides comprehensive CRISPR-based services to create precise cellular and animal models for such investigations.
Contact EDITGENE today to design your custom CRISPR model for 1-acylglycerol-3-phosphate O-acyltransferase activity research.
Frequently Asked Questions About 1-acylglycerol-3-phosphate O-acyltransferase activity
What is 1-acylglycerol-3-phosphate O-acyltransferase activity?
It is the enzymatic activity that converts lysophosphatidic acid to phosphatidic acid by adding an acyl group from acyl-CoA, encoded by GO:0003841.
What genes are involved in 1-acylglycerol-3-phosphate O-acyltransferase activity?
The main genes are the AGPAT family, including AGPAT1 through AGPAT11, as well as related genes like GPAT and PNPLA3 [1,2,7].
What diseases are associated with AGPAT2 mutations?
Mutations in AGPAT2 cause congenital generalized lipodystrophy, a severe disorder characterized by lack of adipose tissue and metabolic complications.
How is 1-acylglycerol-3-phosphate O-acyltransferase activity measured?
It is typically measured using enzymatic assays with radiolabeled or fluorescent substrates, followed by thin-layer chromatography or mass spectrometry [1,2].
Is AGPAT11 involved in cancer?
Yes, AGPAT11 is upregulated in breast and cervical cancers, and its activity is elevated in cancer cell lines, suggesting a role in tumor lipid metabolism.
What is the role of AGPAT in ferroptosis?
Maintaining homeostasis of docosahexaenoate-containing phospholipids through AGPAT activity protects against ferroptosis, a form of cell death.
Can CRISPR be used to study AGPAT function?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to study AGPAT genes and their roles in lipid metabolism and disease [1,4].
What is the difference between AGPAT and GPAT?
GPAT adds the first acyl group to glycerol-3-phosphate, while AGPAT adds the second acyl group to lysophosphatidic acid; they are sequential enzymes in glycerolipid synthesis.
How does AGPAT activity affect mitochondria?
Loss of AGPAT activity can lead to mitochondrial dysfunction and altered lipid droplet formation, as shown in bacterial and eukaryotic models.
What are the therapeutic implications of targeting AGPAT?
AGPAT isoforms are potential targets for treating metabolic disorders, cancer, and ferroptosis-related diseases, and CRISPR models can aid drug discovery [2,3,5].
Conclusion
1-acylglycerol-3-phosphate O-acyltransferase activity (GO:0003841) is a fundamental enzymatic step in glycerophospholipid and triacylglycerol biosynthesis. Its dysregulation is linked to severe metabolic diseases, cancer, and ferroptosis. The AGPAT family of enzymes, encoded by multiple genes, exhibits tissue-specific expression and substrate specificity, making them attractive targets for therapeutic intervention. Advances in CRISPR-based models and lipidomics will continue to unravel the complex regulation and pathophysiological roles of this activity, paving the way for novel treatments.
References
- 1. Haque W et al.. 2005. Enzymatic activity of naturally occurring 1-acylglycerol-3-phosphate-O-acyltransferase 2 mutants associated with congenital generalized lipodystrophy.. Biochem Biophys Res Commun 327(2):446-53 PMID: 15629135
- 2. Agarwal AK et al.. 2010. Enzymatic activity of the human 1-acylglycerol-3-phosphate-O-acyltransferase isoform 11: upregulated in breast and cervical cancers.. J Lipid Res 51(8):2143-52 PMID: 20363836
- 3. Deng Y et al.. 2025. Protection against ferroptosis through maintaining homeostasis of docosahexaenoate-containing phospholipids.. Mol Cell 85(18):3474-3485.e5 PMID: 40934923
- 4. Zhao C et al.. 2025. The 1-acylglycerol-3-phosphate acyltransferase Slc1 is required to regulate mitochondria and lipid droplets.. Microbiol Res 293:128080 PMID: 39892319
- 5. Cakmak E et al.. 2021. Chanarin-Dorfman Syndrome: A comprehensive review.. Liver Int 41(5):905-914 PMID: 33455044
- 6. Agarwal AK et al.. 2007. Functional characterization of human 1-acylglycerol-3-phosphate-O-acyltransferase isoform 9: cloning, tissue distribution, gene structure, and enzymatic activity.. J Endocrinol 193(3):445-57 PMID: 17535882
- 7. Sherman DJ et al.. 2025. PNPLA3-I148M is a neomorph that interferes with two primary hepatic triglyceride clearance pathways.. Cell Rep 44(10):116371 PMID: 41046517
