GO:0004144 diacylglycerol O-acyltransferase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0004144 describes the enzymatic activity that catalyzes the final step of triacylglycerol synthesis: acyl-CoA + 1,2-diacylglycerol = CoA + triacylglycerol.
• The two principal enzymes carrying this activity in mammals are DGAT1 and DGAT2, which differ in structure, localization, and regulation [2,3].
• DGAT1 and DGAT2 are implicated in obesity-associated colon cancer progression and in lipid droplet biology [1,3].
• DGAT2 reduction causes lipid dysregulation in psoriasis models, linking this activity to skin inflammation.
• DGAT1 inhibition can increase plasma liver enzymes via intestinal toxicity in rats, highlighting safety considerations for inhibitors.
• Studying GO:0004144 requires integrated approaches including CRISPR knockout, point mutation, knock-in, overexpression, and lipidomics [1,2,4].
Description
Diacylglycerol O-acyltransferase (DGAT) activity, formally annotated as GO:0004144, catalyzes the terminal and committed step in the synthesis of triacylglycerol (TG), the main storage form of metabolic energy in eukaryotes. This activity transfers an acyl group from acyl-CoA to the sn-3 position of 1,2-diacylglycerol, releasing CoA and forming TG. Because TG synthesis sits at the crossroads of energy storage, lipid signaling, and membrane biogenesis, DGAT activity is a central node in metabolic research [1,3]. Two structurally unrelated enzymes, DGAT1 and DGAT2, carry this activity in mammals and are the focus of intense investigation in obesity, cancer, and inflammatory disease [1,2,4]. Understanding GO:0004144 therefore requires both mechanistic enzymology and disease-relevant models [2,5].
diacylglycerol O-acyltransferase activity At A Glance
| GO ID | GO:0004144 |
|---|---|
| GO term | diacylglycerol O-acyltransferase activity |
| Ontology | molecular_function |
| Synonym | 1,2-diacylglycerol acyltransferase activity; acyl-CoA:1,2-diacylglycerol O-acyltransferase activity; diacylglycerol acyltransferase activity; diglyceride acyltransferase activity; diglyceride O-acyltransferase activity; palmitoyl-CoA-sn-1,2-diacylglycerol acyltransferase activity |
| Definition | Catalysis of the reaction: acyl-CoA + 1,2-diacylglycerol = CoA + triacylglycerol. |
| Major function | Final step of triacylglycerol biosynthesis |
| Representative enzymes | DGAT1, DGAT2 |
| Substrates | Acyl-CoA and 1,2-diacylglycerol |
| Products | CoA and triacylglycerol |
What Is GO:0004144?
GO:0004144 (diacylglycerol O-acyltransferase activity) is a molecular function defined by the reaction: acyl-CoA + 1,2-diacylglycerol = CoA + triacylglycerol. In other words, it is the catalytic activity that attaches a fatty acyl chain from an acyl-CoA donor onto diacylglycerol to produce triacylglycerol. This activity is synonymous with diglyceride acyltransferase activity and is executed by enzymes such as DGAT1 and DGAT2.
Why Is diacylglycerol O-acyltransferase activity Important in Cell Biology?
GO:0004144 is important because triacylglycerol synthesis is fundamental to energy homeostasis, and its dysregulation contributes to metabolic disease, cancer, and inflammation. DGAT1 and DGAT2, the main enzymes with this activity, are being pursued as therapeutic targets, and understanding their mechanism and regulation is essential for drug development and disease modeling [1,2,4,5].
• DGAT1 and DGAT2 levels are increased in obesity-facilitated colon cancer progression.
• DGAT2 facilitates lipid droplet growth via ER-to-lipid droplet targeting.
• DGAT2 reduction and lipid dysregulation drive psoriasis development in keratinocyte-specific SPRY1-deficient mice.
• DGAT1 inhibition can cause intestinal villi shedding and increased permeability, raising plasma ALT and AST in rats.
• DGAT1 affects endoplasmic reticulum stress and inflammatory responses in ketotic dairy cows.
• Chenodeoxycholic acid suppresses AML progression via ROS/p38 MAPK/DGAT1 pathway and M2 macrophage polarization.
• Gut microbiota regulates hepatic ketogenesis and lipid accumulation by disrupting bile acid metabolism, involving DGAT-related pathways.
• DGAT activity is a target for anti-obesity and anti-diabetic therapies.
• DGAT enzymes are critical for lipid droplet formation and cellular lipid storage.
• Studying DGAT activity helps understand metabolic reprogramming in cancer and immune cells [1,7].
What Happens During diacylglycerol O-acyltransferase activity?
Substrate binding and catalysis
In simple terms: The enzyme grabs a diacylglycerol and an acyl-CoA, then stitches the fatty acid onto the diacylglycerol to make triacylglycerol.
DGAT enzymes bind 1,2-diacylglycerol and acyl-CoA, then catalyze the transfer of the acyl group to the sn-3 position of diacylglycerol, releasing CoA and forming triacylglycerol. The reaction is the final committed step in TG synthesis.
DGAT1 vs DGAT2: distinct enzymes, same activity
In simple terms: Two different proteins can do this job, but they work in different places and ways.
DGAT1 and DGAT2 are structurally unrelated and share little sequence homology, yet both catalyze the same reaction. DGAT1 is a member of the membrane-bound O-acyltransferase family, while DGAT2 belongs to the DGAT2/acyl-CoA:monoacylglycerol acyltransferase family. They also differ in subcellular localization and regulation.
Role in lipid droplet formation
In simple terms: The triacylglycerol made by this activity is stored in lipid droplets, and DGAT2 helps build those droplets.
DGAT2 is targeted from the endoplasmic reticulum to lipid droplets by Rab1b, facilitating lipid droplet growth. This shows that DGAT activity is spatially organized to support lipid storage.
Physiological and pathological contexts
In simple terms: This activity matters in fat tissue, liver, skin, and even cancer.
DGAT1 and DGAT2 levels are increased in obesity-facilitated colon cancer progression. DGAT2 reduction causes lipid dysregulation in psoriasis models. DGAT1 affects ER stress and inflammation in ketotic dairy cows. DGAT1 inhibition can cause intestinal toxicity in rats.
Key Genes Involved in GO:0004144 diacylglycerol O-acyltransferase activity
The following genes and proteins are directly associated with diacylglycerol O-acyltransferase activity (GO:0004144) or its regulation.
| Gene | Major Role | Research Relevance |
|---|---|---|
| DGAT1 | Catalyzes final step of TG synthesis; MBOAT family | Obesity, colon cancer, intestinal toxicity, ER stress [1,2,5,6] |
| DGAT2 | Catalyzes final step of TG synthesis; DGAT2 family | Lipid droplet growth, psoriasis, lipid dysregulation [3,4] |
| Rab1b | Facilitates ER-to-lipid droplet targeting of DGAT2 | Lipid droplet biology |
| SPRY1 | Regulates DGAT2 reduction in keratinocytes | Psoriasis development |
| MOGAT1 | Related acyltransferase, monoacylglycerol pathway | Lipid metabolism |
| MOGAT2 | Related acyltransferase, monoacylglycerol pathway | Lipid metabolism |
| MOGAT3 | Related acyltransferase, monoacylglycerol pathway | Lipid metabolism |
| PNPLA2 | Lipid droplet lipase, opposes DGAT function | Lipid turnover |
| PLIN1 | Lipid droplet coat protein | Lipid storage regulation |
| PLIN2 | Lipid droplet coat protein | Lipid storage regulation |
| CIDEC | Lipid droplet protein | Lipid droplet fusion |
| FABP4 | Fatty acid binding protein | Lipid trafficking |
| SREBF1 | Transcription factor regulating lipogenic genes | Lipogenesis |
| SREBF2 | Transcription factor regulating cholesterol/lipid genes | Lipogenesis |
| PPARG | Master regulator of adipogenesis | Adipose tissue biology |
| CEBPA | Adipogenic transcription factor | Adipocyte differentiation |
| INSIG1 | Regulates SREBP processing | Lipid homeostasis |
| SCAP | SREBP cleavage-activating protein | Lipid homeostasis |
How Is diacylglycerol O-acyltransferase activity Regulated?
DGAT activity is regulated at multiple levels. DGAT2 is targeted to lipid droplets by Rab1b, which controls its spatial activity. In ketotic dairy cows, DGAT1 expression is linked to ER stress and inflammatory responses in adipose tissue. Chenodeoxycholic acid modulates DGAT1 via the ROS/p38 MAPK pathway in AML. Gut microbiota can influence hepatic lipid accumulation and ketogenesis through bile acid metabolism, indirectly affecting DGAT-related pathways. These examples show that DGAT activity is subject to transcriptional, post-transcriptional, and signaling regulation.
diacylglycerol O-acyltransferase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| DGAT1/DGAT2 | Obesity-associated colon cancer | Diet-induced obesity mouse model with colon cancer xenografts |
| DGAT2 | Psoriasis | Keratinocyte-specific SPRY1 knockout mice |
| DGAT1 | AML | AML cell lines and mouse models treated with chenodeoxycholic acid |
| DGAT1 | Intestinal toxicity | Rats treated with DGAT1 inhibitor |
| DGAT1 | Ketosis in dairy cows | Ketotic dairy cow adipose tissue |
Obesity-associated colon cancer
Increased levels of DGAT1 and DGAT2 mediate obesity-facilitated colon cancer progression, suggesting that targeting these enzymes could be a therapeutic strategy.
Psoriasis
DGAT2 reduction and lipid dysregulation drive psoriasis development in keratinocyte-specific SPRY1-deficient mice, linking DGAT activity to skin inflammation.
Acute myeloid leukemia (AML)
Chenodeoxycholic acid suppresses AML progression by promoting lipid peroxidation via the ROS/p38 MAPK/DGAT1 pathway and inhibiting M2 macrophage polarization.
Metabolic and intestinal toxicity
DGAT1 inhibition increases plasma ALT and AST via intestinal villi shedding and increased permeability in rats, highlighting potential side effects of DGAT1 inhibitors. DGAT1 also affects ER stress and inflammation in ketotic dairy cows.
From diacylglycerol O-acyltransferase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does DGAT1 loss affect tumor growth? | DGAT1 knockout mice or cancer cell lines |
| How does DGAT2 localization affect lipid droplets? | DGAT2 tagged knock-in with Rab1b mutants |
| What is the role of DGAT2 in skin inflammation? | Keratinocyte-specific DGAT2 knockout or overexpression |
| Can DGAT1 inhibition cause intestinal damage? | Rat model with DGAT1 inhibitor treatment |
| How does DGAT1 affect ER stress in adipose tissue? | Adipose-specific DGAT1 knockout in dairy cows |
| Does DGAT1 modulate AML progression? | AML xenografts with DGAT1 overexpression or knockout |
How to Study the diacylglycerol O-acyltransferase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Lipidomics (LC-MS) | Triacylglycerol and lipid species | Assessing DGAT activity in cells/tissues [1,4] |
| DGAT activity assay | Enzyme kinetics | In vitro characterization of DGAT1/2 |
| Confocal microscopy | Lipid droplet size and localization | Studying DGAT2 targeting |
| RT-qPCR | mRNA expression of DGAT1/2 | Gene regulation studies |
| Western blot | Protein levels of DGAT1/2 | Expression analysis |
| CRISPR knockout | Gene function loss | Phenotypic studies [1,4] |
| Overexpression | Gain-of-function | Rescue or disease modeling |
| RNA-seq | Transcriptome changes | Pathway analysis |
Lipidomics and mass spectrometry
Lipidomics can quantify triacylglycerol species and other lipids to assess DGAT activity in cells and tissues [1,4].
Enzymatic assays
In vitro DGAT activity assays using radiolabeled acyl-CoA or fluorescent substrates measure the conversion of diacylglycerol to triacylglycerol.
Imaging of lipid droplets
Fluorescence microscopy with lipid droplet dyes (e.g., BODIPY) visualizes lipid droplet size and number, reflecting DGAT function.
Gene expression analysis
RT-qPCR and RNA-seq measure DGAT1 and DGAT2 mRNA levels in response to metabolic or inflammatory stimuli [6,8].
How CRISPR Can Be Used to Study GO:0004144 diacylglycerol O-acyltransferase activity
Knockout
CRISPR knockout of DGAT1 or DGAT2 eliminates the respective enzyme activity, allowing researchers to study its role in lipid metabolism, cancer, and inflammation [1,4].
Point Mutation
Point mutations can be introduced into the catalytic domain of DGAT1 or DGAT2 to dissect residues critical for acyl transfer, as guided by structural studies.
Knock-in
Knock-in of tagged DGAT2 (e.g., GFP) enables live-cell imaging of its trafficking from ER to lipid droplets.
Overexpression
Overexpression of DGAT1 or DGAT2 in cell lines increases triacylglycerol synthesis and lipid droplet formation, useful for gain-of-function studies.
How EDITGENE Supports diacylglycerol O-acyltransferase activity Research
Researchers studying diacylglycerol O-acyltransferase activity-related genes often need to determine whether a candidate gene is causally involved in lipid metabolism, disease progression, or drug response. EDITGENE provides comprehensive CRISPR-based services to accelerate this research.
Contact EDITGENE today to design your custom CRISPR model for diacylglycerol O-acyltransferase activity research.
Frequently Asked Questions About diacylglycerol O-acyltransferase activity
What is diacylglycerol O-acyltransferase activity?
It is the enzymatic activity (GO:0004144) that catalyzes the final step of triacylglycerol synthesis: acyl-CoA + 1,2-diacylglycerol = CoA + triacylglycerol.
What genes are involved in diacylglycerol O-acyltransferase activity?
The main genes are DGAT1 and DGAT2, which encode enzymes that carry out this activity.
What is the difference between DGAT1 and DGAT2?
DGAT1 and DGAT2 are structurally unrelated enzymes that catalyze the same reaction but differ in localization, regulation, and tissue expression [2,3].
How is diacylglycerol O-acyltransferase activity regulated?
It is regulated by targeting (e.g., Rab1b-mediated DGAT2 trafficking), signaling pathways (ROS/p38 MAPK), and transcriptional control [3,6,7].
What diseases are associated with DGAT1 and DGAT2?
They are linked to obesity-associated colon cancer, psoriasis, AML, and metabolic disorders [1,4,7].
How can I study DGAT activity in the lab?
Common methods include lipidomics, enzymatic assays, microscopy of lipid droplets, and CRISPR knockout/overexpression [1,2,3].
What is the role of DGAT2 in lipid droplets?
DGAT2 is targeted to lipid droplets by Rab1b and promotes lipid droplet growth.
Can DGAT1 inhibitors cause side effects?
Yes, DGAT1 inhibition can cause intestinal villi shedding and increased permeability, leading to elevated liver enzymes in rats.
What model systems are used to study DGAT2 in skin?
Keratinocyte-specific SPRY1-deficient mice show DGAT2 reduction and psoriasis-like phenotypes.
How does obesity affect DGAT levels in cancer?
Obesity increases DGAT1 and DGAT2 levels, which mediate colon cancer progression.
Conclusion
Diacylglycerol O-acyltransferase activity (GO:0004144) is a central enzymatic function in triacylglycerol synthesis, executed by DGAT1 and DGAT2. Its roles in energy storage, lipid droplet biology, and disease make it a key research target. Understanding its mechanism and regulation requires integrated approaches, and CRISPR-based models are invaluable for dissecting its functions in health and disease [1,2,3,4,5,6,7,8].
References
- 1. Ghimire J et al.. 2025. Obesity-Facilitated Colon Cancer Progression Is Mediated by Increased Diacylglycerol O-Acyltransferases 1 and 2 Levels.. Gastroenterology 168(2):286-299.e6 PMID: 39299402
- 2. Wang L et al.. 2020. Structure and mechanism of human diacylglycerol O-acyltransferase 1.. Nature 581(7808):329-332 PMID: 32433610
- 3. Malis Y et al.. 2024. Rab1b facilitates lipid droplet growth by ER-to-lipid droplet targeting of DGAT2.. Sci Adv 10(22):eade7753 PMID: 38809969
- 4. Li YY et al.. 2025. DGAT2 reduction and lipid dysregulation drive psoriasis development in keratinocyte-specific SPRY1-deficient mice.. JCI Insight 10(17) PMID: 40694426
- 5. Yokoyama H et al.. 2024. Diacylglycerol O-acyltransferase 1 inhibitor increases plasma alanine aminotransferase and aspartate aminotransferase activities via a shedding of the intestinal villi and an increase in intestinal permeability in rats.. Toxicol Lett 400:16-23 PMID: 39096942
- 6. Xu Q et al.. 2022. Effects of diacylglycerol O-acyltransferase 1 (DGAT1) on endoplasmic reticulum stress and inflammatory responses in adipose tissue of ketotic dairy cows.. J Dairy Sci 105(11):9191-9205 PMID: 36114053
- 7. Liu J et al.. 2022. Chenodeoxycholic acid suppresses AML progression through promoting lipid peroxidation via ROS/p38 MAPK/DGAT1 pathway and inhibiting M2 macrophage polarization.. Redox Biol 56:102452 PMID: 36084349
- 8. Luo Z et al.. 2025. Gut microbiota regulates hepatic ketogenesis and lipid accumulation in ketogenic diet-induced hyperketonemia by disrupting bile acid metabolism.. Gut Microbes 17(1):2496437 PMID: 40268803
