Sensitive red fluorescent indicators for real-time visualization of potassium ion dynamics in vivo.

ABSTRACT: Potassium ion (K+) dynamics are vital for various biological processes. However, the limited availability of detection tools for tracking intracellular and extracellular K+ has impeded a comprehensive understanding of the physiological roles of K+ in intact biological systems. In this study, we developed two novel red genetically encoded potassium indicators (RGEPOs), RGEPO1 and RGEPO2, through a combination of directed evolution in Escherichia coli and subsequent optimization in mammalian cells. RGEPO1, targeted to the extracellular membrane, and RGEPO2, localized in the cytoplasm, exhibited positive K+-specific fluorescence response with affinities of 2.4 and 43.3 mM in HEK293FT cells, respectively. We employed RGEPOs for real-time monitoring of subsecond K+ dynamics in cultured neurons,

SUBMITTER: Yang L 

PROVIDER: S-EPMC12456824 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature