GO:1990777 lipoprotein particle: Components, Assembly and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:1990777 lipoprotein particle is a cellular_component term describing a spherical particle of non-covalently associated proteins and lipids, such as plasma lipoproteins that transport lipids in blood or lymph.
• Lipoprotein particles are routinely quantified by nuclear magnetic resonance spectroscopy, which resolves particle number and size across VLDL, LDL, and HDL subclasses.
• Discordance between lipoprotein particle number and cholesterol content is common and affects cardiovascular risk interpretation.
• Apolipoprotein B-containing lipoproteins are central to atherogenesis and are causal drivers of atherosclerotic cardiovascular disease.
• Cumulative exposure to atherogenic lipoprotein particles in young adults predicts incident atherosclerotic cardiovascular disease later in life.
• Dietary composition, including plant-based diet indices and protein source, measurably shifts lipoprotein particle subclass profiles.
• Therapeutic targeting of apolipoprotein C-III with plozasiran alters lipoprotein particle size and number in hypertriglyceridemia.
Description
GO:1990777 lipoprotein particle is a Gene Ontology cellular_component term that defines a spherical particle containing non-covalently associated proteins and lipids. The canonical examples are plasma lipoprotein particles that transport lipids through blood or lymph. These particles are not membrane-bound organelles but dynamic supramolecular assemblies whose protein and lipid composition determines their metabolic fate and their relationship to disease. Because lipoprotein particles are the principal vehicles for moving hydrophobic lipids in an aqueous environment, their structure, assembly, and regulation are of broad interest to cell biologists, biochemists, and clinical researchers. Quantitative measurement of lipoprotein particle number and size is now a standard component of cardiovascular risk assessment, and nuclear magnetic resonance spectroscopy has become a widely used platform for this purpose. However, particle number and cholesterol content can be discordant, meaning that cholesterol-based assays alone may misclassify risk in some individuals. This discordance has motivated research into apolipoprotein B-containing particles as direct atherogenic agents and into cumulative lifetime exposure as a determinant of atherosclerotic cardiovascular disease. At the same time, experimental work has shown that lipoprotein particle formation can be triggered by non-classical mechanisms, such as the proapoptotic protein tBid, expanding the biological contexts in which this GO term is relevant. Dietary and pharmacological interventions further demonstrate that lipoprotein particle profiles are modifiable, with plant-based diets, protein source, and apolipoprotein C-III targeting all producing measurable changes in particle number or size. Together, these findings establish GO:1990777 lipoprotein particle as a central node linking lipid metabolism, vascular biology, and precision cardiovascular medicine.
lipoprotein particle At A Glance
| GO ID | GO:1990777 |
|---|---|
| GO term | lipoprotein particle |
| Ontology | cellular_component |
| Synonym | None listed in QuickGO |
| Definition | A spherical particle containing non-covalently associated proteins and lipids; examples are plasma lipoprotein particles which transport lipids in the blood or lymph |
| Major function | Transport of lipids through aqueous compartments such as blood and lymph |
| Representative particles | VLDL, LDL, HDL, and related apolipoprotein B-containing particles |
| Common measurement | Nuclear magnetic resonance spectroscopy for particle number and size |
| Disease relevance | Atherosclerotic cardiovascular disease and hypertriglyceridemia |
What Is GO:1990777?
In the Gene Ontology, GO:1990777 lipoprotein particle is a cellular_component term defined as a spherical particle containing non-covalently associated proteins and lipids. The definition explicitly gives plasma lipoprotein particles, which transport lipids in the blood or lymph, as examples. The term has no listed synonyms. The key features are the spherical geometry, the non-covalent association between protein and lipid constituents, and the physiological role in lipid transport. This distinguishes lipoprotein particles from membrane-bound vesicles and from covalent lipoprotein conjugates. The term is agnostic to the specific apolipoprotein composition, so it encompasses apolipoprotein B-containing particles such as VLDL and LDL as well as apolipoprotein A-I-containing HDL particles.
Why Is lipoprotein particle Important in Cell Biology?
GO:1990777 lipoprotein particle matters because these particles are the primary carriers of lipids in circulation and because their number, size, and composition are directly linked to atherosclerotic cardiovascular disease. Nuclear magnetic resonance spectroscopy has made it possible to quantify lipoprotein particle number and subclass distribution in clinical and epidemiological studies. Discordance between particle number and cholesterol content means that two individuals with identical LDL cholesterol can have very different atherogenic particle burdens, which changes risk stratification and treatment decisions. Apolipoprotein B-containing lipoproteins are now understood as causal agents in atherogenesis rather than passive biomarkers. Cumulative exposure to atherogenic particles over decades, beginning in young adulthood, predicts incident cardiovascular events. Diet and emerging therapies can remodel particle profiles, confirming that this GO term describes a modifiable biological system with direct clinical consequences.
• Lipoprotein particles transport hydrophobic lipids through blood and lymph, a function that cannot be performed by free lipids in aqueous solution.
• Particle number and cholesterol content can be discordant, so cholesterol-only assays may underestimate or overestimate atherogenic risk.
• Apolipoprotein B-containing lipoproteins are directly involved in atherogenesis and plaque formation.
• Cumulative lifetime exposure to atherogenic lipoprotein particles predicts incident atherosclerotic cardiovascular disease.
• Non-classical triggers such as tBid can promote lipoprotein particle formation, linking apoptosis machinery to lipid assembly.
• Dietary protein source and saturated fat intake modify atherogenic lipoprotein measures in randomized trials.
• Plant-based diet indices are associated with favorable lipoprotein particle subclass profiles.
• Apolipoprotein C-III inhibition with plozasiran changes lipoprotein particle size and number in hypertriglyceridemia.
• Lipoprotein particle profiling supports precision cardiovascular risk assessment beyond standard lipid panels.
• The term provides a shared ontology anchor for integrating lipidomics, proteomics, and clinical cardiovascular data.
Structure and Composition of lipoprotein particle
Spherical core-shell architecture
In simple terms: A lipoprotein particle is like a tiny ball of fat wrapped in a soap-like shell so it can travel through blood.
Lipoprotein particles are spherical assemblies in which a hydrophobic core of triglycerides and cholesteryl esters is surrounded by a surface monolayer of phospholipids, free cholesterol, and apolipoproteins. This architecture is required for transporting water-insoluble lipids through plasma and lymph. Nuclear magnetic resonance spectroscopy exploits the distinct magnetic environments of core and surface lipids to resolve particle number and size across VLDL, LDL, and HDL subclasses. The non-covalent nature of the protein-lipid association, as stated in the GO definition, allows particles to be remodeled by lipases and lipid transfer proteins without covalent bond formation.
Apolipoprotein B-containing particles
In simple terms: ApoB is the structural backbone of the particles that most strongly drive artery disease.
Apolipoprotein B (APOB) is the principal structural apolipoprotein of VLDL, IDL, and LDL, and each of these particles contains exactly one molecule of APOB. Because APOB remains with the particle throughout its metabolic cascade, it serves as a stoichiometric marker of atherogenic particle number. Apolipoprotein B-containing lipoproteins are directly implicated in atherogenesis, and their cumulative exposure is associated with incident atherosclerotic cardiovascular disease. Discordance between APOB particle number and LDL cholesterol content is common and affects risk interpretation.
Apolipoprotein A-I and HDL particles
In simple terms: HDL particles use apoA-I as their main protein scaffold and participate in reverse cholesterol transport.
HDL particles are built around apolipoprotein A-I (APOA1) and related apolipoproteins, and they participate in reverse cholesterol transport from peripheral tissues to the liver. Nuclear magnetic resonance spectroscopy resolves HDL particle subclasses and shows that HDL particle number and size are distinct metrics from HDL cholesterol. Plant-based diet indices have been associated with favorable shifts in lipoprotein particle subclass profiles, including HDL subclasses. The GO term encompasses these particles because they share the defining spherical, non-covalent protein-lipid architecture.
Minor apolipoproteins and particle remodeling
In simple terms: Small apolipoproteins act like traffic signals that tell the particle where to go and when to unload its fat.
Apolipoprotein C-III (APOC3) and other minor apolipoproteins modulate the metabolism of triglyceride-rich particles. Targeting APOC3 with plozasiran changes lipoprotein particle size and number in hypertriglyceridemia, demonstrating that minor apolipoproteins are tractable therapeutic nodes. Remodeling of particles by lipases and transfer proteins occurs without covalent modification of the particle constituents, consistent with the non-covalent association described in the GO definition. These remodeling events change particle size and subclass distribution, which are captured by nuclear magnetic resonance profiling.
Non-classical particle formation
In simple terms: Some particles can form through unexpected cellular processes, not only through the classical secretory pathway.
Experimental work has shown that the proapoptotic protein tBid can promote lipoprotein particle formation, indicating that particle assembly is not restricted to classical hepatic and intestinal secretion. This finding expands the cellular contexts in which GO:1990777 lipoprotein particle is relevant and suggests that apoptosis-related proteins can influence lipid particle assembly. Such non-classical mechanisms may be important in disease states characterized by cell death and lipid dysregulation.
Key Genes Involved in GO:1990777 lipoprotein particle
The following genes and proteins are central to the structure, assembly, remodeling, and clinical measurement of lipoprotein particles as defined by GO:1990777.
| Gene | Major Role | Research Relevance |
|---|---|---|
| APOB | Structural apolipoprotein of VLDL, IDL, and LDL; one molecule per particle | Stoichiometric marker of atherogenic particle number and target of cardiovascular risk studies |
| APOA1 | Principal structural apolipoprotein of HDL particles | Central to HDL particle subclass analysis and reverse cholesterol transport research |
| APOC3 | Modulates triglyceride-rich lipoprotein metabolism | Therapeutic target; plozasiran alters particle size and number in hypertriglyceridemia |
| APOE | Mediates receptor-mediated clearance of remnant lipoproteins | Relevant to remnant particle clearance and neurodegeneration research |
| MTTP | Microsomal triglyceride transfer protein; required for APOB lipidation | Essential for assembly of APOB-containing particles |
| LPL | Lipoprotein lipase; hydrolyzes triglycerides in chylomicrons and VLDL | Determines particle remodeling and subclass distribution |
| CETP | Cholesteryl ester transfer protein; transfers lipids between lipoproteins | Shapes HDL and LDL particle size and number |
| PCSK9 | Regulates LDL receptor recycling | Indirectly controls LDL particle clearance and plasma particle number |
| LDLR | Mediates hepatic uptake of APOB-containing particles | Determines residence time and cumulative exposure to atherogenic particles |
| SCARB1 | HDL receptor mediating selective cholesteryl ester uptake | Relevant to HDL particle metabolism |
| ABCA1 | Cholesterol efflux transporter; lipidates nascent APOA1 | Required for HDL particle formation |
| ABCG1 | Cholesterol efflux transporter to HDL particles | Contributes to HDL particle maturation |
| BID | Proapoptotic BH3 protein; tBid promotes lipoprotein particle formation | Links apoptosis machinery to non-classical particle assembly |
| SORT1 | Sortilin; modulates hepatic VLDL secretion | Candidate modifier of APOB particle production |
| ANGPTL3 | Inhibits lipoprotein lipase and endothelial lipase | Regulates triglyceride-rich particle clearance |
| APOA5 | Activates lipoprotein lipase on triglyceride-rich particles | Modifies particle size and number |
| NR1H3 | Liver X receptor alpha; regulates lipid metabolism genes | Transcriptional control of lipoprotein particle production |
| INSIG1 | Regulates SREBP processing and lipogenesis | Indirectly affects substrate availability for particle assembly |
How Is lipoprotein particle Regulated?
Lipoprotein particle number and composition are regulated at multiple levels. Transcriptional control of APOB, MTTP, and lipogenic genes determines the rate of particle secretion from liver and intestine. Post-translational regulation of lipoprotein lipase and its inhibitors ANGPTL3 and APOA5 controls triglyceride hydrolysis and particle remodeling. Receptor-mediated clearance via LDLR and related receptors determines particle residence time and cumulative exposure. Pharmacological inhibition of APOC3 with plozasiran reduces particle number and increases particle size in hypertriglyceridemia, demonstrating that circulating particle profiles are acutely modifiable. Dietary factors, including protein source and plant-based diet indices, also regulate lipoprotein particle subclass distributions. Nuclear magnetic resonance spectroscopy provides a quantitative readout of these regulatory changes.
lipoprotein particle and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| APOB | Atherosclerotic cardiovascular disease; atherogenic particle burden | APOB knockout hepatocyte cell line; APOB point-mutation knock-in |
| APOC3 | Hypertriglyceridemia; triglyceride-rich particle metabolism | APOC3 overexpression and knockout hepatocyte models |
| LDLR | Familial hypercholesterolemia; impaired particle clearance | LDLR knockout HepG2 cells; LDLR knock-in reporter |
| BID | Apoptosis-associated lipoprotein particle formation | BID knockout and tBid overexpression cell models |
| APOA1 | HDL particle formation and reverse cholesterol transport | APOA1 knockout and tagged knock-in hepatocyte models |
Atherosclerotic cardiovascular disease
Apolipoprotein B-containing lipoprotein particles are directly involved in atherogenesis, and their cumulative exposure predicts incident atherosclerotic cardiovascular disease. Discordance between particle number and cholesterol content means that some individuals with normal LDL cholesterol still carry a high atherogenic particle burden. Nuclear magnetic resonance spectroscopy quantifies particle number and size, supporting more precise risk assessment. Cumulative exposure beginning in young adulthood is associated with subsequent events, emphasizing the importance of lifetime particle burden.
Hypertriglyceridemia and remnant particles
Triglyceride-rich lipoprotein particles accumulate in hypertriglyceridemia, and their remnants are atherogenic. Targeting APOC3 with plozasiran changes lipoprotein particle size and number, providing a therapeutic strategy for this condition. ANGPTL3 and APOA5 regulate the hydrolysis and clearance of these particles, and their dysfunction contributes to remnant accumulation. Particle profiling by nuclear magnetic resonance spectroscopy can monitor therapeutic responses.
Diet-responsive dyslipidemia
Dietary composition modifies atherogenic lipoprotein measures. In a randomized controlled trial, red meat, white meat, and nonmeat protein sources produced different effects on atherogenic lipoprotein measures depending on saturated fat intake. Plant-based diet indices are associated with favorable lipoprotein particle subclass profiles in middle- to older-aged adults. These findings indicate that lifestyle interventions can shift particle number and size, which are quantifiable by nuclear magnetic resonance spectroscopy.
Non-classical particle formation in cell death
The proapoptotic protein tBid can promote lipoprotein particle formation, linking cell death pathways to lipid particle assembly. This observation suggests that lipoprotein particles may form in contexts beyond classical secretion, potentially contributing to disease states characterized by apoptosis and lipid dysregulation. Further research is needed to define the pathological significance of this mechanism.
From lipoprotein particle-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of APOB abolish APOB-containing particle secretion? | APOB knockout hepatocyte cell line |
| Does a specific APOC3 point mutation alter particle size? | APOC3 point-mutation knock-in hepatocyte model |
| Can a tagged apolipoprotein be tracked through particle assembly? | Tagged knock-in of APOA1 or APOB |
| Does overexpression of tBid induce lipoprotein particle formation? | tBid overexpression cell model |
| Which genes regulate lipoprotein particle subclass distribution? | CRISPR library screening in lipid-handling cell lines |
| Does restoration of LDLR rescue particle clearance? | LDLR knock-in in LDLR-deficient cells |
How to Study the lipoprotein particle Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Nuclear magnetic resonance spectroscopy | Lipoprotein particle number and size across subclasses | Clinical and epidemiological particle profiling |
| Apolipoprotein B immunoassay | Stoichiometric marker of atherogenic particle number | Cardiovascular risk assessment |
| Standard lipid panel | Cholesterol and triglyceride concentrations | Initial dyslipidemia screening |
| Cell secretion assay | APOB-containing particle secretion from hepatocytes | Functional testing of assembly genes |
| CRISPR knockout | Loss-of-function effect on particle formation | Causal gene discovery |
| Point-mutation knock-in | Effect of specific variants on particle size or number | Variant functional annotation |
| Overexpression | Gain-of-function effect on particle assembly | Testing tBid and APOC3 |
| CRISPR library screening | Pooled gene requirements for particle phenotypes | Pathway discovery in lipid-handling cells |
Nuclear magnetic resonance spectroscopy
Nuclear magnetic resonance spectroscopy is a primary method for lipoprotein particle analysis, resolving particle number and size across VLDL, LDL, and HDL subclasses. It exploits the distinct magnetic environments of lipids in the particle core and surface, providing quantitative subclass profiles. This method has been used in clinical and epidemiological studies to link particle number to cardiovascular outcomes.
Lipid and apolipoprotein assays
Standard lipid panels measure cholesterol and triglycerides but do not directly count particles, which can lead to discordance with particle number. Apolipoprotein B measurement provides a stoichiometric estimate of atherogenic particle number because each APOB-containing particle carries one APOB molecule. Combining APOB and nuclear magnetic resonance data improves risk interpretation.
Cell-based assembly and secretion assays
Hepatocyte and enterocyte cell models are used to study the assembly and secretion of APOB-containing particles. Knockout of MTTP or APOB abolishes particle secretion, providing a functional readout. Non-classical particle formation can be studied by expressing tBid in cultured cells.
Genetic and pharmacological perturbation
CRISPR knockout, point-mutation knock-in, and overexpression models allow causal testing of candidate genes in lipoprotein particle biology. Pharmacological agents such as plozasiran that target APOC3 provide a benchmark for particle size and number changes. Dietary interventions in randomized trials demonstrate that particle measures respond to environmental inputs.
How CRISPR Can Be Used to Study GO:1990777 lipoprotein particle
Knockout
CRISPR knockout of APOB, MTTP, or other assembly genes abolishes or reduces lipoprotein particle secretion in hepatocyte models, providing a clean loss-of-function readout. Knockout of APOC3 or ANGPTL3 alters triglyceride-rich particle metabolism and can be used to validate therapeutic targets. Pooled knockout screens can identify novel genes required for particle formation or clearance.
Point Mutation
Point-mutation knock-in allows testing of specific variants in APOB, APOC3, or LDLR for their effects on particle size, number, or clearance. This approach is valuable for functional annotation of variants identified in cardiovascular genetics studies. Isogenic cell lines carrying single-nucleotide changes provide controlled comparisons.
Knock-in
Tagged knock-in of APOA1 or APOB enables tracking of particle assembly and secretion using fluorescence or affinity tags. Knock-in of LDLR restores particle clearance in LDLR-deficient cells, modeling familial hypercholesterolemia correction. Knock-in of reporter cassettes under endogenous promoters provides physiological expression control.
Overexpression
Overexpression of tBid induces lipoprotein particle formation in cultured cells, demonstrating a non-classical assembly route. Overexpression of APOC3 increases triglyceride-rich particle levels and alters particle size, modeling hypertriglyceridemia. Overexpression models are useful for gain-of-function studies and for testing pharmacological inhibitors.
How EDITGENE Supports lipoprotein particle Research
Researchers studying lipoprotein particle-related genes often need to determine whether a candidate gene is causally involved in particle assembly, remodeling, or clearance. EDITGENE provides CRISPR-based cell model services that enable loss-of-function, gain-of-function, and variant-specific experiments in relevant cell backgrounds.
Contact EDITGENE today to design your custom CRISPR model for lipoprotein particle research.
Frequently Asked Questions About lipoprotein particle
What is GO:1990777 lipoprotein particle?
GO:1990777 is a Gene Ontology cellular_component term defined as a spherical particle containing non-covalently associated proteins and lipids, with plasma lipoprotein particles that transport lipids in blood or lymph as examples.
What genes are involved in lipoprotein particle formation?
Key genes include APOB, APOA1, APOC3, MTTP, LPL, CETP, LDLR, and ABCA1, among others.
How are lipoprotein particles measured?
Nuclear magnetic resonance spectroscopy is a primary method that resolves particle number and size across VLDL, LDL, and HDL subclasses.
Why is lipoprotein particle number important if cholesterol is already measured?
Particle number and cholesterol content can be discordant, so cholesterol-only assays may misclassify atherogenic risk in some individuals.
Are apolipoprotein B-containing particles atherogenic?
Yes, apolipoprotein B-containing lipoproteins are directly involved in atherogenesis and cumulative exposure predicts cardiovascular events.
Can diet change lipoprotein particle profiles?
Yes, randomized trial data show that protein source and saturated fat intake affect atherogenic lipoprotein measures, and plant-based diet indices are associated with favorable subclass profiles.
What drugs target lipoprotein particles?
Plozasiran, which targets apolipoprotein C-III, changes lipoprotein particle size and number in hypertriglyceridemia.
Can lipoprotein particles form outside classical secretion?
Yes, the proapoptotic protein tBid can promote lipoprotein particle formation in experimental systems.
What cell models are used to study lipoprotein particles?
Hepatocyte and enterocyte cell lines with CRISPR knockout, knock-in, or overexpression of APOB, APOC3, MTTP, and related genes are commonly used.
How does EDITGENE support lipoprotein particle research?
EDITGENE provides knockout, point-mutation, knock-in, overexpression, CRISPR library screening, and bioinformatics services for lipoprotein-related genes.
Conclusion
GO:1990777 lipoprotein particle defines a fundamental cellular assembly that transports lipids through blood and lymph and that is directly linked to atherosclerotic cardiovascular disease. Nuclear magnetic resonance spectroscopy and apolipoprotein B measurement provide complementary readouts of particle number and size, while genetic and pharmacological studies show that these profiles are modifiable. CRISPR-based cell models enable causal testing of candidate genes in particle assembly, remodeling, and clearance, supporting both mechanistic discovery and therapeutic development.
References
- 1. Jeyarajah EJ et al.. 2006. Lipoprotein particle analysis by nuclear magnetic resonance spectroscopy.. Clin Lab Med 26(4):847-70 PMID: 17110242
- 2. Cantey EP et al.. 2018. Discordance between lipoprotein particle number and cholesterol content: an update.. Curr Opin Endocrinol Diabetes Obes 25(2):130-136 PMID: 29324459
- 3. Borén J et al.. 2025. Apolipoprotein B-containing lipoproteins in atherogenesis.. Nat Rev Cardiol 22(6):399-413 PMID: 39743565
- 4. Zheutlin AR et al.. 2025. Cumulative exposure to atherogenic lipoprotein particles in young adults and subsequent incident atherosclerotic cardiovascular disease.. Eur Heart J 46(41):4302-4312 PMID: 40613415
- 5. Ekanayake V et al.. 2018. Lipoprotein Particle Formation by Proapoptotic tBid.. Biophys J 115(3):533-542 PMID: 30017071
- 6. Bergeron N et al.. 2019. Effects of red meat, white meat, and nonmeat protein sources on atherogenic lipoprotein measures in the context of low compared with high saturated fat intake: a randomized controlled trial.. Am J Clin Nutr 110(1):24-33 PMID: 31161217
- 7. Elliott PS et al.. 2023. Plant-based diet indices and lipoprotein particle subclass profiles: A cross-sectional analysis of middle- to older-aged adults.. Atherosclerosis 380:117190 PMID: 37552902
- 8. Ballantyne CM et al.. 2025. Effect of Targeting ApoC-III With Plozasiran on Lipoprotein Particle Size and Number in Hypertriglyceridemia.. J Am Coll Cardiol 85(19):1839-1854 PMID: 40099777
