ABCA2 is a ATP-binding cassette transporter involved in lipid metabolism and myelination. Important for neuronal cholesterol homeostasis.
Abca2 — Atp Binding Cassette Subfamily A Member 2 is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
| Property |
Value |
| Gene Symbol |
ABCA2 |
| Full Name |
ATP-Binding Cassette Subfamily A Member 2 |
| Chr Location |
9q34.3 |
| NCBI Gene ID |
20 |
| OMIM ID |
600047 |
| Ensembl ID |
ENSG00000107331 |
| UniProt ID |
Q9BZC7 |
| Encoded Protein |
ABCA2 Transporter |
| Associated Diseases |
Alzheimer's disease, multiple sclerosis, hereditary spastic paraplegia |
ABCA2 encodes ATP-binding cassette subfamily A member 2, a member of the ABC transporter family. This transporter is primarily involved in lipid transport across cellular membranes, with particular importance in neuronal lipid homeostasis.
Key normal physiological functions include:
- Lipid efflux - Mediates cholesterol and phospholipid efflux to apolipoproteins
- Myelin maintenance - Essential for proper myelin sheath formation and maintenance
- Lysosomal function - Regulates trafficking and function of lysosomes
- Cholesterol homeostasis - Controls neuronal cholesterol levels
- Amyloid metabolism - Influences APP processing and Aβ clearance
- Neuronal development - Required for normal neuronal differentiation
The protein structure includes:
- Two transmembrane domains - 12 transmembrane helices total
- Two nucleotide-binding domains - ATP hydrolysis for transport
- Two extracellular loops - Substrate binding
ABCA2 is a significant genetic risk factor:
- Genetic association - ABCA2 variants associated with increased AD risk
- Cholesterol link - Alters neuronal cholesterol metabolism
- Aβ metabolism - Influences Aβ production and clearance
- Expression changes - ABCA2 expression altered in AD brains
- Recessive mutations cause a form of HSP
- Characterized by lower limb spasticity and weakness
- Associated with white matter abnormalities
- Genetic variants associated with MS susceptibility
- Links to myelin maintenance and repair
ABCA2 is predominantly expressed in neural tissue:
- Highest expression: Brain (cortex, hippocampus, basal ganglia), white matter
- Moderate expression: Spinal cord, peripheral nervous system
- Cellular localization: Lysosomes, endosomes, plasma membrane
- Cell types: Oligodendrocytes, neurons, astrocytes
The Allen Brain Atlas shows high ABCA2 expression in:
- Cortical pyramidal neurons
- Hippocampal neurons
- Oligodendrocytes (white matter)
- Kim et al., ABCA2 as AD risk factor (2009)
- Chen et al., ABCA2 in lipid transport (2010)
- Mack et al., ABCA2 and myelin (2007)
The study of Abca2 — Atp Binding Cassette Subfamily A Member 2 has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
- Pulst et al., SCA2 identification (1996)
- Elden et al., ATXN2 expansions in ALS (2010)
- Bhattacharjee et ATXN2 in RNA metabolism (2011)
- Last et al., Ataxin-2 function and disease (2020)
- Sato et al., ATXN2 in Parkinson's disease (2019)
- Gispert-Sanchez et al., ATXN2 and RNA granules (2015)
- Nonis et al., ATXN2 in diabetes (2022)
- Kumar et al., ATXN2 therapeutic targeting (2021)