Biophysical Characterization of Genetically Encoded Voltage Sensor ASAP1: Dynamic Range Improvement.
Biophys J
; 113(10): 2178-2181, 2017 Nov 21.
Article
em En
| MEDLINE
| ID: mdl-29108650
ABSTRACT
Recent work has introduced a new fluorescent voltage sensor, ASAP1, which can monitor rapid trains of action potentials in cultured neurons. This indicator is based on the Gallus gallus voltage-sensitive phosphatase with the phosphatase domain removed and a circularly permuted GFP placed in the S3-S4 linker. However, many of the biophysical details of this indicator remain unknown. In this work, we study the biophysical properties of ASAP1. Using the cut-open voltage clamp technique, we have simultaneously recorded fluorescence signals and gating currents from Xenopus laevis oocytes expressing ASAP1. Gating charge movement and fluorescence kinetics track closely with each other, although ASAP1 gating currents are significantly faster than those of Ciona intestinalis voltage-sensitive phosphatase. Altering the residue before the first gating charge removes a split in the ASAP1 QV curve, but preserves the accelerated kinetics that allow for the faithful tracking of action potentials in neurons.
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Potenciais de Ação
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Monoéster Fosfórico Hidrolases
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Fenômenos Eletrofisiológicos
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Neurônios
Limite:
Animals
Idioma:
En
Revista:
Biophys J
Ano de publicação:
2017
Tipo de documento:
Article