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Title: A sensitive and specific genetically-encoded potassium ion biosensor for in vivo applications across the tree of life
Potassium ion (K + ) plays a critical role as an essential electrolyte in all biological systems. Genetically-encoded fluorescent K + biosensors are promising tools to further improve our understanding of K + -dependent processes under normal and pathological conditions. Here, we report the crystal structure of a previously reported genetically-encoded fluorescent K + biosensor, GINKO1, in the K + -bound state. Using structure-guided optimization and directed evolution, we have engineered an improved K + biosensor, designated GINKO2, with higher sensitivity and specificity. We have demonstrated the utility of GINKO2 for in vivo detection and imaging of K + dynamics in multiple model organisms, including bacteria, plants, and mice.  more » « less
Award ID(s):
2037828
PAR ID:
10402286
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; « less
Editor(s):
Dutzler, Raimund
Date Published:
Journal Name:
PLOS Biology
Volume:
20
Issue:
9
ISSN:
1545-7885
Page Range / eLocation ID:
e3001772
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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