Motor deficit in a Drosophila model of mucolipidosis type IV due to defective clearance of apoptotic cells

TitleMotor deficit in a Drosophila model of mucolipidosis type IV due to defective clearance of apoptotic cells
Publication TypeJournal Article
Year of Publication2008
AuthorsVenkatachalam K, A Long A, Elsaesser R, Nikolaeva D, Broadie K, Montell C
JournalCell
Volume135
Pagination838-51
Date Published2008 Nov 28
ISSN1097-4172
KeywordsAnimals, Apoptosis, Disease Models, Animal, Drosophila, Humans, Mucolipidoses, Neurodegenerative Diseases, TRPM Cation Channels
Abstract

Disruption of the Transient Receptor Potential (TRP) mucolipin 1 (TRPML1) channel results in the neurodegenerative disorder mucolipidosis type IV (MLIV), a lysosomal storage disease with severe motor impairments. The mechanisms underlying MLIV are poorly understood and there is no treatment. Here, we report a Drosophila MLIV model, which recapitulates the key disease features, including abnormal intracellular accumulation of macromolecules, motor defects, and neurodegeneration. The basis for the buildup of macromolecules was defective autophagy, which resulted in oxidative stress and impaired synaptic transmission. Late-apoptotic cells accumulated in trpml mutant brains, suggesting diminished cell clearance. The accumulation of late-apoptotic cells and motor deficits were suppressed by expression of trpml(+) in neurons, glia, or hematopoietic cells. We conclude that the neurodegeneration and motor defects result primarily from decreased clearance of apoptotic cells. Since hematopoietic cells in humans are involved in clearance of apoptotic cells, our results raise the possibility that bone marrow transplantation may limit the progression of MLIV.

DOI10.1016/j.cell.2008.09.041
Alternate JournalCell
PubMed ID19041749
PubMed Central IDPMC2649760
Grant ListEY08117 / EY / NEI NIH HHS / United States
NS41740 / NS / NINDS NIH HHS / United States
R01 EY008117-20 / EY / NEI NIH HHS / United States