Cresyl violet: a superior fluorescent lysosomal marker

Area of Science:

• Cell Biology
• Biochemistry
• Fluorescence Microscopy

Background:

• Lysosomes and acidic vacuoles are crucial organelles involved in cellular degradation and waste removal.
• Accurate visualization of these compartments is essential for understanding cellular processes.
• Existing acidotropic probes often suffer from photobleaching, photoconversion, or interference with cellular function.

Purpose of the Study:

• To characterize cresyl violet as a novel fluorescent probe for labeling acidic cellular compartments.
• To evaluate its suitability as a lysosomal marker in diverse cell types.
• To compare its properties with existing acidotropic probes.

Main Methods:

• Characterization of cresyl violet's membrane permeability and localization in various cell lines (yeast, Drosophila, human, murine, canine).
• Assessment of its spectral properties, including compatibility with other fluorophores and photostability.
• Evaluation of its impact on organellar pH and buffering capacity at effective labeling concentrations.

Main Results:

• Cresyl violet is a membrane-permeant fluorophore that specifically localizes to lysosomes and acidic vacuoles.
• It is insensitive to physiological cation concentrations and exhibits high photostability without photoconversion.
• Labeling with cresyl violet does not alter organellar pH or buffering capacity.
• It is compatible with green, red, and far-red fluorophores.

Conclusions:

• Cresyl violet is a superior lysosomal marker due to its unique spectral properties, photostability, and lack of cellular interference.
• Its affordability and performance make it a valuable tool for fluorescence microscopy and cell biology research.
• This probe offers a significant advantage over existing acidotropic markers for visualizing acidic organelles.