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Optimized Negative Staining: a High-throughput Protocol for Examining Small and Asymmetric Protein Structure by Electron Microscopy
Published on: August 15, 2014
Apolipoprotein E: far more than a lipid transport protein
1Gladstone Institute of Cardiovascular Disease, University of California at San Francisco, San Francisco, California 94141-9100, USA. rmahley@gladstone.ucsf.edu
Annual Review of Genomics and Human Genetics
|November 10, 2001
Summary
Apolipoprotein E (apoE) isoforms influence health beyond lipid transport, impacting Alzheimer's disease and immune function. Understanding these apoE variants is crucial for disease risk assessment and potential therapeutic strategies.
Area of Science:
- Genetics and Molecular Biology
- Neuroscience
- Cardiovascular Science
Background:
- Apolipoprotein E (apoE) is critical for lipoprotein metabolism and cardiovascular health.
- Beyond lipid transport, apoE plays roles in Alzheimer's disease, cognitive function, and immunoregulation.
- ApoE exhibits polymorphism with three major isoforms: apoE2, apoE3, and apoE4.
Purpose of the Study:
- To elucidate the diverse biological functions of apolipoprotein E (apoE) beyond its established role in lipoprotein metabolism.
- To investigate the functional consequences of different apoE isoforms (apoE2, apoE3, apoE4) on human health and disease.
- To explore the implications of apoE isoform-specific effects on cardiovascular disease, Alzheimer's disease, and cognitive function.
Main Methods:
- Analysis of genetic variations in the apolipoprotein E gene locus.
- Comparison of functional consequences associated with different apoE isoforms (apoE2, apoE3, apoE4).
- Review of existing literature on apoE's role in lipoprotein metabolism, cardiovascular disease, and neurological disorders.
Main Results:
- ApoE isoforms differ by single amino acid substitutions, leading to significant functional variations.
- ApoE4 is associated with increased risk for atherosclerosis and Alzheimer's disease, and impaired cognitive function.
- ApoE2 is linked to type III hyperlipoproteinemia and variable effects on atherosclerosis risk.
Conclusions:
- Apolipoprotein E isoforms have profound, isoform-specific effects on diverse biological processes, including lipid metabolism, cardiovascular health, and neurological function.
- The distinct functional profiles of apoE2 and apoE4, compared to the common apoE3, highlight their differential disease associations.
- Evolutionary selection pressures on apoE isoforms may be influenced by their effects on survival before reproductive age.
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