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
en 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.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Visión Ocular
/
Encéfalo
/
Lóbulo Óptico de Animales no Mamíferos
/
Células Fotorreceptoras de Invertebrados
/
Proteínas de Drosophila
/
Drosophila melanogaster
/
Canales de Potasio de la Superfamilia Shaker
/
Canales de Potasio Shal
/
Interneuronas
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
J Comp Physiol A Neuroethol Sens Neural Behav Physiol
Asunto de la revista:
CIENCIAS DO COMPORTAMENTO
/
NEUROLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Alemania