Projects per year
Beta III spectrin is present throughout the elaborate dendritic tree of cerebellar Purkinje cells and is required for normal neuronal morphology and cell survival. Spinocerebellar ataxia type 5 (SCA5) and spectrin associated autosomal recessive cerebellar ataxia type 1 are human neurodegenerative diseases involving progressive gait ataxia and cerebellar atrophy. Both disorders appear to result from loss of β-III spectrin function. Further elucidation of β-III spectrin function is therefore needed to understand disease mechanisms and identify potential therapeutic options. Here, we report that β-III spectrin is essential for the recruitment and maintenance of ankyrin R at the plasma membrane of Purkinje cell dendrites. Two SCA5-associated mutations of β-III spectrin both reduce ankyrin R levels at the cell membrane. Moreover, a wild-type β-III spectrin/ankyrin-R complex increases sodium channel levels and activity in cell culture, whereas mutant β-III spectrin complexes fail to enhance sodium currents. This suggests impaired ability to form stable complexes between the adaptor protein ankyrin R and its interacting partners in the Purkinje cell dendritic tree is a key mechanism by which mutant forms of β-III spectrin cause ataxia, initially by Purkinje cell dysfunction and exacerbated by subsequent cell death.
- AXON INITIAL SEGMENTS
- ATAXIA TYPE 5
- HEREDITARY SPHEROCYTOSIS
- MEMBRANE SKELETON
FingerprintDive into the research topics of 'β-III spectrin underpins ankyrin R function in Purkinje cell dendritic trees: Protein complex critical for sodium channel activity is impaired by SCA5-associated mutations'. Together they form a unique fingerprint.
- 1 Finished
10/01/11 → 9/12/15
- Deanery of Biomedical Sciences - Senior Lecturer
- Centre for Discovery Brain Sciences
- Edinburgh Neuroscience
- Euan MacDonald Centre for Motor Neuron Disease Research
Person: Academic: Research Active