Organelle-Directed Staudinger Reaction Enabling Fluorescence-on Resolution of Mitochondrial Electropotentials via a Self-Immolative Charge Reversal Probe

Abstract

Organelles often feature parameters pertinent to functions and yet responsive to biochemical stress. The electropotential across the mitochondrial membrane (ΔΨm) is a crucial mediator of cell fates. Herein we report a bioorthogonal reaction enabled fluorescence-on probing of ΔΨm alterations featuring anionic fluorescein-triphenylphosphonium diad (F-TPP), which is released via intramitochondria Staudinger reaction triggered self-immolation of o-azidomethylbenzoylated F-TPP. Compared to classical cationic mitochondria-specific dyes, F-TPP is hydrophilic and negatively charged. Effectively discerning ΔΨm changes upon diverse stress inducers, the organelle-directed bioorthogonal imaging strategy offers unprecedented choices to probe mitochondrial biology with functional molecules that are otherwise inaccessible via physiological organelle-probe affinity.

Bioorthogonal Removal of 3-Isocyanopropyl Groups Enables the Controlled Release of Fluorophores and Drugs in Vivo

“…The ability to chemically control the release of reporter probes, bioactive compounds, and biomacromolecules using bioorthogonal reactions is opening opportunities for the development of innovative research tools, diagnostics, and therapeutics . Applications in diverse fields such as biosensing, cell imaging, gasoemission, and activity control of nucleic acids and proteins exemplify the potential of such transformations. Moreover, there is an interest in the clinical translation of dissociative bioorthogonal reactions as chemically responsive antibody-drug conjugates and prodrugs …”

Structural Modification Orientated Multifunctional AIE Fluorescence Probes: Organelles Imaging and Effective Photosensitizer for Photodynamic Therapy

“…As referred to above, TPE‐IQ‐O, TPE‐IQ‐CN, and TPE‐IQ‐TPA are cationic compounds, TPE‐IQ‐O specially target to the mitochondrial and we speculate that the binding of such molecules to mitochondria changes the MMP, making it toxic to cells. To prove this inference, MMP was measured with a commercial JC‐1 dye on the basis i) it shows red fluorescence upon aggregation in healthy negatively charged mitochondria, and ii) it becomes green emissive when mitochondrial membrane(∆ψ m ) is reduced and mitochondria is damaged . So, we use JC‐1 dye as an indicator to discern whether TPE‐IQ‐O destroys membrane of mitochondrial.…”

Organelle-Redirected Chameleon Sensor-Enabled Live Cell Imaging of Mitochondrial DNA

“…Live cell imaging of mtDNA with classical DNA sensors is challenging owing to interference of nuDNA. Complementing de novo design of mtDNA-reporting agents − and intraorganelle bioorthogonal chemistries, − our method takes advantage of organelle-directed fluorogenic intercalation to achieve live cell imaging of mtDNA, which would facilitate the study of dynamic mtDNA, a major danger-associated molecular pattern underlying diverse pathological disorders.…”