Neurons In Spinocerebellar Ataxia Type 3 (Machado Joseph Disease) is an important cell type in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Spinocerebellar Ataxia Type 3 (SCA3) neurons represent a specific neuronal population affected in Machado-Joseph disease (MJD), the most common dominant ataxia worldwide. These neurons harbor the pathogenic polyglutamine expansion in the ATXN3 gene and demonstrate characteristic degeneration primarily affecting cerebellar outflow pathways, brainstem nuclei, and spinal cord neurons. [1]
| Property | Value | [2]
|----------|-------| [3]
| Category | Neurodegeneration-associated neurons | [4]
| Gene | ATXN3 (Ataxin-3) | [5]
| Mutation | CAG repeat expansion (polyglutamine) | [6]
| Normal Repeat | 12-44 CAG repeats | [7]
| Pathogenic Repeat | 52-86+ CAG repeats | [8]
| Protein | Ataxin-3 ( Machado-Joseph disease protein) | [9]
| Brain Regions Affected | Cerebellar dentate nucleus, brainstem, spinal cord |
The ATXN3 gene (also known as MJD1) is located on chromosome 14q32.12 and encodes the ataxin-3 protein, a deubiquitinating enzyme involved in protein quality control:
The polyglutamine expansion in ataxin-3 leads to:
The dentate nucleus is the primary site of pathology:
Multiple brainstem nuclei are affected:
Ataxin-3 in healthy neurons:
Pathological changes include:
SCA3/MJD presents with:
Ataxia: Progressive cerebellar dysfunction
Parkinsonism: In some patients
Spasticity: Upper motor neuron signs
Peripheral neuropathy: Sensory involvement
Gene silencing
Protein-targeting therapies
Cellular protection
Multiple clinical trials are investigating:
The study of Neurons In Spinocerebellar Ataxia Type 3 (Machado Joseph Disease) 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.
Geschwind DH, et al. [Ataxin-3: a neuronal deubiquitinase. Neuron. 1997](https://doi.org/10.1016/s0896-6273(00). 1997. ↩︎
McLoughlin HS, et al. Pathogenesis of SCA3: therapeutic implications. J Mol Neurosci. 2016. 2016. ↩︎
Ross CA, et al. Polyglutamine diseases: molecular biology and pathogenesis. Nat Rev Neurosci. 2013. 2013. ↩︎
Costa Mdo C, et al. Animal models of SCA3. Cerebellum. 2013. 2013. ↩︎
Matos CA, et al. Polyglutamine diseases: the special case of ataxin-3. Prog Neurobiol. 2019. 2019. ↩︎
Paulson HL, et al. Dominant ataxias. Continuum. 2016. 2016. ↩︎
Sakai H, et al. Dentate nucleus pathology in SCA3. J Neurol Sci. 2019. 2019. ↩︎
Matsumura R, et al. Neuropathology of SCA3. Brain Pathol. 1997. 1997. ↩︎
Chen L, et al. Therapeutic strategies for SCA3. Mov Disord. 2019. 2019. ↩︎