Live-cell biosensors based on the fluorescence lifetime of environment-sensing dyes.
CELL REPORTS METHODS 2024;
4:100734. [PMID:
38503289 PMCID:
PMC10985238 DOI:
10.1016/j.crmeth.2024.100734]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/13/2023] [Accepted: 02/26/2024] [Indexed: 03/21/2024]
Abstract
In this work, we examine the use of environment-sensitive fluorescent dyes in fluorescence lifetime imaging microscopy (FLIM) biosensors. We screened merocyanine dyes to find an optimal combination of environment-induced lifetime changes, photostability, and brightness at wavelengths suitable for live-cell imaging. FLIM was used to monitor a biosensor reporting conformational changes of endogenous Cdc42 in living cells. The ability to quantify activity using phasor analysis of a single fluorophore (e.g., rather than ratio imaging) eliminated potential artifacts. We leveraged these properties to determine specific concentrations of activated Cdc42 across the cell.
Collapse