| 2002 |
AGPAT2 encodes 1-acylglycerol-3-phosphate O-acyltransferase 2, which catalyzes the acylation of lysophosphatidic acid (LPA) to form phosphatidic acid (PA), a key intermediate in the biosynthesis of triacylglycerol and glycerophospholipids; loss-of-function mutations cause congenital generalized lipodystrophy type 1 (CGL1). |
Genetic linkage mapping, mutation identification, and biochemical characterization of enzyme function |
Nature genetics |
High |
11967537
|
| 2009 |
In Agpat2-null mice, loss of AGPAT2 leads to severe lipodystrophy affecting both white and brown adipose tissue, with a ~4-fold increase in hepatic de novo fatty acid biosynthesis and markedly increased MOGAT1 (monoacylglycerol acyltransferase isoform 1) expression, indicating activation of an alternative monoacylglycerol pathway for triglyceride biosynthesis in the absence of AGPAT2. |
Agpat2 knockout mouse model, gene expression analysis, lipid metabolic flux measurements, fat-free diet intervention |
Cell metabolism |
High |
19187773
|
| 2011 |
Human AGPAT2 and AGPAT1 have similar in vitro substrate specificities for lysophosphatidic acid and acyl-CoA; protein homology modeling with GPAT1 reveals similar tertiary structure; when co-expressed, AGPAT1 and AGPAT2 co-localize to the endoplasmic reticulum; however, restoring AGPAT activity specifically in liver via adenoviral overexpression failed to ameliorate hepatic steatosis in Agpat2-/- mice, indicating that hepatic steatosis is primarily a consequence of insulin resistance and loss of adipose tissue rather than hepatic AGPAT2 deficiency. |
In vitro enzymatic substrate specificity assays, protein homology modeling, co-immunolocalization, adenoviral overexpression in knockout mice |
The Journal of biological chemistry |
High |
21873652
|
| 2012 |
AGPAT2 modulates adipogenesis through regulation of the lipome: AGPAT2 deficiency alters levels of phosphatidic acid, lysophosphatidic acid, phosphatidylinositol species, and the PPARγ inhibitor cyclic phosphatidic acid, leading to reduced Akt activation and impaired PI3K/Akt and PPARγ pathway signaling; constitutively active Akt partially restores lipogenesis, and PPARγ agonist pioglitazone partially rescues the adipogenic defect. |
Muscle-derived multipotent cells from CGL patients, retroviral AGPAT2 rescue, AGPAT2 knockdown and overexpression in 3T3-L1, lipidomics, Akt activation assays, constitutively active Akt expression |
Diabetes |
High |
22872237
|
| 2014 |
Specific molecular species of phosphatidic acid (PA; C16:0/18:1 and C18:1/20:4), which accumulate in Agpat2-/- mouse livers (~5-fold elevated), enhance hepatic glucose production (HGP) in primary hepatocytes by upregulating gluconeogenic enzymes glucose-6-phosphatase and PEPCK; this PA-induced HGP is suppressed by insulin in wild-type hepatocytes but not in Agpat2-/- hepatocytes, establishing PA as a driver of hepatic insulin resistance in lipodystrophy. |
Primary hepatocyte cultures, exogenous PA/LPA treatment, gluconeogenic enzyme expression analysis, insulin signaling assays in WT vs Agpat2-/- hepatocytes |
The Journal of biological chemistry |
High |
24425876
|
| 2015 |
Seipin oligomers (dodecamers) can directly interact with AGPAT2 during adipogenesis, as demonstrated by co-immunoprecipitation and atomic force microscopy; a single seipin complex can simultaneously bind both AGPAT2 and lipin 1 with a defined orientation, physically scaffolding these critical regulators of the PA biosynthetic pathway; stabilizing the seipin-AGPAT2 interaction increases nuclear PPARγ accumulation. |
Co-immunoprecipitation, immunofluorescence, atomic force microscopy, direct protein interaction reconstitution |
Molecular metabolism |
High |
25737955
|
| 2016 |
AGPAT2 is essential for postnatal maintenance (but not fetal formation) of white and brown adipose tissue; Agpat2-/- newborn mice have normal adipose tissue mass, but lose it during the first postnatal week due to adipocyte death and inflammatory infiltration; ultrastructurally, Agpat2-/- adipocytes lack caveolae and have abnormal mitochondria and lipid droplets; differentiated Agpat2-/- MEFs have 3-fold increased phosphatidic acid levels and impaired adipogenesis. |
Light and electron microscopy, immunoblots, qPCR, electrospray ionization tandem mass spectrometry (ESI-MS/MS) phospholipid profiling, PPARγ overexpression rescue in Agpat2-/- MEFs |
Molecular metabolism |
High |
27408775
|
| 2018 |
AGPAT2 expression is a direct transcriptional target of HIF-1: HIF-1α binds a specific hypoxia response element (HRE) in the AGPAT2 promoter (confirmed by ChIP), and mutation of this HRE abolishes hypoxic activation of the AGPAT2 promoter; AGPAT2 knockdown reduces lipid droplet accumulation and cell viability under hypoxia and increases etoposide sensitivity. |
siRNA knockdown of HIF-1α, reporter gene assay with AGPAT2 promoter, chromatin immunoprecipitation (ChIP), HRE mutagenesis, siRNA knockdown of AGPAT2 with cell viability and lipid droplet readouts |
Biochimica et biophysica acta. Molecular and cell biology of lipids |
High |
29908837
|
| 2020 |
Seipin directly interacts with GPAT3 in addition to AGPAT2, and a single seipin complex can simultaneously bind both GPAT3 and AGPAT2; loss of seipin, AGPAT2, or GPAT3 each impairs induction of early adipocyte differentiation markers in cultured cells. |
Co-immunoprecipitation, adipogenic differentiation assays in cultured preadipocytes, GPAT3-null mouse analysis |
Scientific reports |
Medium |
32094408
|
| 2021 |
AGPAT2 directly interacts with and stabilizes CDP-diacylglycerol synthases (CDS1/2), forming functional complexes that promote metabolism of PA along the CDP-DAG pathway; AGPAT2 deficiency compromises CDS stability and decreases CDS enzymatic activity in both cell lines and mouse liver, explaining the paradoxical PA accumulation seen in AGPAT2-deficient cells despite AGPAT2 being a PA-generating enzyme. |
Co-immunoprecipitation, CDS activity assays, lipidomics in cell lines and mouse liver, AGPAT2 knockout models |
Nature communications |
High |
34824276
|
| 2021 |
In differentiated Agpat2-/- adipocytes, decreased caveolae number is not associated with changes in plasma membrane cholesterol or sphingolipid levels, nor with reduced caveolin-1 or cavin-1 protein levels; however, increased plasma membrane phosphatidylserine content may contribute to the caveolae defect. |
Plasma membrane purification by ultracentrifugation, electron microscopy, lipidomics (sterol, sphingolipid, phospholipid), immunoblot for caveolae-associated proteins |
Biochimica et biophysica acta. Molecular basis of disease |
Medium |
33989739
|
| 2023 |
Adipose-tissue-specific re-expression of human AGPAT2 in Agpat2-null mice (regulated by doxycycline) resulted in partial regeneration of both white and brown adipose tissue; turning off AGPAT2 expression caused total loss of regenerated adipose tissue, demonstrating that AGPAT2 is essential for adipocyte differentiation in vivo and that adipocytes require continuous AGPAT2 activity for survival. |
Doxycycline-regulated adipose-tissue-specific transgenic expression in Agpat2-null mice, adipose tissue mass measurement, ex vivo differentiation of stromal vascular fraction cells, leptin secretion measurement |
iScience |
High |
37752957
|
| 2025 |
AGPAT2-generated phosphatidic acid (PA) drives ER tubulation by interacting with and supplying PA to the PA-binding dynamin-related GTPase DRP1, which subsequently tubulates the ER independently of GTP hydrolysis and oligomerization; AGPAT2 knockout shifts ER morphology from tubules to sheets, and ectopic expression of PA phosphatase LIPIN1 similarly converts ER tubules to sheets; AGPAT2 was identified by screening 18 PA-generating enzymes for effects on ER morphology. |
Gene knockout, 3D structural analysis by FIB-SEM, super-resolution microscopy, lipidomics, AlphaFold structural modeling, in vitro reconstitution of ER tubulation, in vitro AGPAT2 activity assays, LIPIN1 ectopic expression |
Nature communications |
High |
41387688
|
| 2012 |
Both the p.Cys48Arg and p.Leu228Pro AGPAT2 mutant proteins show significantly reduced protein levels compared to wild-type AGPAT2 despite equivalent mRNA levels, and fail to rescue adipogenesis in AGPAT2-deficient preadipocytes, indicating these mutations cause loss of function primarily through protein instability rather than mRNA reduction. |
Expression of wild-type and mutant AGPAT2 in AGPAT2-deficient preadipocyte cell lines, mRNA and protein quantification, adipogenic rescue assay |
JIMD reports |
Medium |
23430550
|