An indole-based fluorescent chemosensor targeting the autophagosome

Area of Science:

• Cell Biology
• Molecular Biology
• Biochemistry

Background:

• Autophagy is a fundamental cellular process responsible for degrading and recycling damaged organelles and misfolded proteins.
• Accurate imaging of autophagosomes, the hallmark vesicles of autophagy, is crucial for understanding this process in various physiological and pathological conditions.
• Existing imaging techniques may have limitations in specificity or applicability to live-cell imaging.

Purpose of the Study:

• To develop and characterize a novel fluorescent probe for the selective and efficient imaging of autophagosomes in live cells.
• To validate the probe's performance in established cellular models of autophagy.

Main Methods:

• Synthesis of an indole-embedded fluorescent naphthalimide derivative.
• Live-cell fluorescence confocal microscopy to visualize autophagosomes.
• Co-localization studies using a known autophagosome marker (LC3-RFP).
• Application of the probe in cellular models induced by endoplasmic reticulum (ER) stress and nutrient starvation.

Main Results:

• The developed fluorescent naphthalimide probe successfully generated intense punctate signals in fluorescence confocal images, indicative of autophagosome localization.
• Significant co-localization was observed between the probe signal and the established autophagosome marker, LC3-RFP.
• The probe demonstrated efficacy in imaging autophagosomes in live cells subjected to ER stress and starvation, validating its functional capability in autophagy-related cellular models.

Conclusions:

• The novel indole-embedded fluorescent naphthalimide is a potent and selective tool for live-cell imaging of autophagosomes.
• This probe facilitates the study of autophagy dynamics under various cellular conditions, including stress and starvation.
• The developed imaging agent holds promise for advancing research in autophagy-related cellular mechanisms and diseases.