Distinct expression of potassium channels regulates visual response properties of lamina neurons in Drosophila melanogaster.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol
; 206(2): 273-287, 2020 03.
Article
em En
| MEDLINE
| ID: mdl-31823004
ABSTRACT
The computational organization of sensory systems depends on the diversification of individual cell types with distinct signal-processing capabilities. The Drosophila visual system, for instance, splits information into channels with different temporal properties directly downstream of photoreceptors in the first-order interneurons of the OFF pathway, L2 and L3. However, the biophysical mechanisms that determine this specialization are largely unknown. Here, we show that the voltage-gated Ka channels Shaker and Shal contribute to the response properties of the major OFF pathway input L2. L3 calcium response kinetics postsynaptic to photoreceptors resemble the sustained calcium signals of photoreceptors, whereas L2 neurons decay transiently. Based on a cell-type-specific RNA-seq data set and endogenous protein tagging, we identified Shaker and Shal as the primary candidates to shape L2 responses. Using in vivo two-photon imaging of L2 calcium signals in combination with pharmacological and genetic perturbations of these Ka channels, we show that the wild-type Shaker and Shal function is to enhance L2 responses and cell-autonomously sharpen L2 kinetics. Our results reveal a role for Ka channels in determining the signal-processing characteristics of a specific cell type in the visual system.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Visão Ocular
/
Encéfalo
/
Lobo Óptico de Animais não Mamíferos
/
Células Fotorreceptoras de Invertebrados
/
Proteínas de Drosophila
/
Drosophila melanogaster
/
Superfamília Shaker de Canais de Potássio
/
Canais de Potássio Shal
/
Interneurônios
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Comp Physiol A Neuroethol Sens Neural Behav Physiol
Assunto da revista:
CIENCIAS DO COMPORTAMENTO
/
NEUROLOGIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Alemanha