Biogenesis of GPI-anchored proteins is essential for surface expression of sodium channels in zebrafish Rohon-Beard neurons to respond to mechanosensory stimulation.
Development
; 137(10): 1689-98, 2010 May.
Article
em En
| MEDLINE
| ID: mdl-20392743
ABSTRACT
In zebrafish, Rohon-Beard (RB) neurons are primary sensory neurons present during the embryonic and early larval stages. At 2 days post-fertilization (dpf), wild-type zebrafish embryos respond to mechanosensory stimulation and swim away from the stimuli, whereas mi310 mutants are insensitive to touch. During approximately 2-4 dpf, wild-type RB neurons undergo programmed cell death, which is caused by sodium current-mediated electrical activity, whereas mutant RB cells survive past 4 dpf, suggesting a defect of sodium currents in the mutants. Indeed, electrophysiological recordings demonstrated the generation of action potentials in wild-type RB neurons, whereas mutant RB cells failed to fire owing to the reduction of voltage-gated sodium currents. Labeling of dissociated RB neurons with an antibody against voltage-gated sodium channels revealed that sodium channels are expressed at the cell surface in wild-type, but not mutant, RB neurons. Finally, in mi310 mutants, we identified a mis-sense mutation in pigu, a subunit of GPI (glycosylphosphatidylinositol) transamidase, which is essential for membrane anchoring of GPI-anchored proteins. Taken together, biogenesis of GPI-anchored proteins is necessary for cell surface expression of sodium channels and thus for firings of RB neurons, which enable zebrafish embryos to respond to mechanosensory stimulation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Células Receptoras Sensoriais
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Peixe-Zebra
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Canais de Sódio
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Glicosilfosfatidilinositóis
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Mecanotransdução Celular
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Proteínas de Membrana
Limite:
Animals
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article