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Expansion mutation within polyglutamine (polyQ) tract proteins is known to underlie a number of severe neurodegenerative disorders such as Huntington’s Disease and Spinocerebellar Ataxia. Using a bioinformatics approach, we have identied a novel protein, FAM171B, that contains a stretch of 14 consecutive glutamines. Using in situ hybridization and immunohistochemistry experiments, our data strongly suggests that FAM171B is widely expressed in the brain with abundant expression in the hippocampus, cortex, and cerebellum. To begin elucidating FAM171B sub-cellular location we are using confocal uorescence imaging of GFP-fusion tagged FAM171B and anti-FAM171B antibodies in vitro. Our ndings indicate that FAM171B displays a punctate/vesicular staining pattern throughout the cytoplasm of human glioblastoma tissue culture cells and primary mouse cortical neurons. FAM171B localization is particularly enriched in the peri-nuclear region and adjacent to the plasma membrane. Current studies are utilizing organelle specic markers to verify sub-cellular locale and live-cell imaging to assay whether FAM171B may trac between intracellular compartments.
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The Novel Protein FAM171B is recruited into Intracellular PolyQ Aggregates
Expansion mutation within polyglutamine (polyQ) tract proteins is known to underlie a number of severe neurodegenerative disorders such as Huntington’s Disease and Spinocerebellar Ataxia. One of the pathologic hallmarks of polyQ expansion disease is the aggregation of mutant proteins into intracellular inclusion bodies. Our lab is actively investigating FAM171B- a relatively uncharacterized protein that also contains a stretch of consecutive glutamines within its primary amino acid sequence and is likely expressed in the nervous system. Since it too contains a short polyQ stretch, we surmised that FAM171B may also be recruited into polyQ aggregates formed by known pathologic proteins. To test this hypothesis, we transfected cells with an expanded version of SCA7-GFP to form intracellular aggregates, and utilized FAM171B specific antibodies, immunofluorescence, and confocal microscopy to assay FAM171B’s intracellular location in relation to the SCA7 inclusion bodies. Our findings indicate that a portion of FAM171B does indeed alter its normally dispersed cytoplasmic subcellular distribution into SCA7 aggregates that locate near the peri-nuclear region of human glioblastoma tissue culture cells. Thus, the novel protein FAM171B may play a role in the molecular mechanisms underlying polyQ disease pathology.
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- Award ID(s):
- 1726859
- PAR ID:
- 10201842
- Date Published:
- Journal Name:
- Annual meeting of the Society for Neuroscience
- ISSN:
- 0091-6528
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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