Live axonal transport disruption by mutant huntingtin fragments in Drosophila motor neuron axons

Autor: C. Sinadinos, T. Burbidge-King, D. Soh, L.M. Thompson, J.L. Marsh, A. Wyttenbach, A.K. Mudher
Jazyk: angličtina
Rok vydání: 2009
Předmět:
Zdroj: Neurobiology of Disease, Vol 34, Iss 2, Pp 389-395 (2009)
Druh dokumentu: article
ISSN: 1095-953X
DOI: 10.1016/j.nbd.2009.02.012
Popis: Huntington's Disease is a neurodegenerative condition caused by a polyglutamine expansion in the huntingtin (Htt) protein, which aggregates and also causes neuronal dysfunction. Pathogenic N-terminal htt fragments perturb axonal transport in vitro. To determine whether this occurs in vivo and to elucidate how transport is affected, we expressed htt exon 1 with either pathogenic (HttEx1Q93) or non-pathogenic (HttEx1Q20) polyglutamine tracts in Drosophila. We found that HttEx1Q93 expression causes axonal accumulation of GFP-tagged fast axonal transport vesicles in vivo and leads to aggregates within larval motor neuron axons. Time-lapse video microscopy, shows that vesicle velocity is unchanged in HttEx1Q93-axons compared to HttEx1Q20-axons, but vesicle stalling occurs to a greater extent. Whilst HttEx1Q93 expression did not affect locomotor behaviour, external heat stress unveiled a locomotion deficit in HttEx1Q93 larvae. Therefore vesicle transport abnormalities amidst axonal htt aggregation places a cumulative burden upon normal neuronal function under stressful conditions.
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