A Carbonized Fluorescent Nucleolus Probe Discloses RNA Reduction in the Process of Mitophagy

Abstract

Mitophagy is a complicated process of cell metabolism that exhibits dynamic spatiotemporal coordination between multiple organelles. Despite its relevance to nucleoli, visualizing the distribution of nucleolar RNA in the process of mitophagy remains a great challenge because of the difficulty in specifically labelling RNA.Herein, we demonstrate a robust carbonized fluorescent probe with folic acid (FA) and m-phenylenediamine (m-PD) as the precursors, which displays superior RNA-anchoring ability and fast cellular permeability to tag nucleolar RNA in living cells. More importantly, this probe possesses spontaneous blinking behavior in physiological conditions, which is suitable for nanoscopic imaging of subtle changes in the distribution of nucleolar RNA. Overall, this work presents a new way for in situ observation of nanoscopic behavior of nucleolar RNA in living cells, providing a powerful approach for further exploration of cellular metabolism in mitophagy.

PDA–PEI-Copolymerized Nanodots with Tailorable Fluorescence Emission and Quenching Properties for the Sensitive Ratiometric Fluorescence Sensing of miRNA in Serum

“…Fluorescence nanodots have attracted much attention for biomedical applications. − To investigate the biomedical applications of PDA–PEI nanodots, the cellular uptake behavior of PDA–PEI was evaluated by incubating with HeLa cells for different durations. As shown in Figure S12, the cell uptake of PDA–PEI nanodots was clearly observed after HeLa cells were incubated with 30 μg/mL PDA–PEI nanodots for 0.5 h, indicating that PDA–PEI nanodots can enter cells within a short time.…”

Advances in the Development of Water-Soluble Fluorogenic Probes for Bioimaging of Hypochlorite/Hypochlorous Acid in Cells and Organisms

“…Recently, single-molecule localization microscopy (SMLM) techniques with precision localization have been widely applied in live cell imaging. − Therefore, SMLM could become a dominant tool for visualizing the intracellular structural morphology with a lateral resolution range of 20–30 nm to study new biological roles of HOCl/OCl – . Due to aqueous solubility, high photon counts, favorable biocompatibility, and the eco-friendly nature, fluorescent carbon dots could be a suitable alternative to organic dyes. , We expect researchers in this field to focus on developing new classes of molecules with improved photophysical properties such as super-resolution imaging, high photostability, NIR/NIR-II emission region, instant response ability, etc. So far, HOCl/OCl – specific probes have been developed for either monitoring or imaging intracellular HOCl/OCl – .…”

“…Recently, single-molecule localization microscopy (SMLM) techniques with precision localization have been widely applied in live cell imaging. 37 − 39 Therefore, SMLM could become a dominant tool for visualizing the intracellular structural morphology with a lateral resolution range of 20–30 nm to study new biological roles of HOCl/OCl – . Due to aqueous solubility, high photon counts, favorable biocompatibility, and the eco-friendly nature, fluorescent carbon dots could be a suitable alternative to organic dyes.…”

“…Due to aqueous solubility, high photon counts, favorable biocompatibility, and the eco-friendly nature, fluorescent carbon dots could be a suitable alternative to organic dyes. 38 , 39 We expect researchers in this field to focus on developing new classes of molecules with improved photophysical properties such as super-resolution imaging, high photostability, NIR/NIR-II emission region, instant response ability, etc. So far, HOCl/OCl – specific probes have been developed for either monitoring or imaging intracellular HOCl/OCl – .…”

One-Pot Three Carbon Dots with Various Lifetimes Rooted in Different Decarboxylation Degrees for Matrix-Free, Anti-Oxygen, and Time-Resolved Information Encryption and Cellular Imaging

“…Optical imaging is commonly used to identify biotargets and their biochemical processes in cells, tissues, and animals. − Traditional fluorescent probes offer two-dimensional signals (wavelength and intensity) only, and the signals can experience interference with an endogenous background fluorescence that covers the entire visible light region. This leads to inaccurate results, and even false signals, due to the spectral overlap between short-lived emission of probe and autofluorescence. − Room temperature phosphorescence (RTP) imaging can acquire three-dimensional signals including wavelength, intensity, and lifetime.…”