Lysosomes are multifunctional organelles involved in macromolecule degradation, nutrient sensing, and autophagy. Live imaging has revealed lysosome subpopulations with dynamics and characteristic cellular localization. An as‐yet unanswered question is whether lysosomes are spatially organized to coordinate and integrate their functions. Combined with super‐resolution microscopy, we designed a small organic fluorescent probe—TPAE—that targeted lysosomes with a large Stokes shift. When we analyzed the spatial organization of lysosomes against mitochondria in different cell lines with this probe, we discovered different distance distribution patterns between lysosomes and mitochondria during increased autophagy flux. By using
This study introduces a rapid, volumetric live-cell imaging technique for visualizing autofluorescent sub-cellular structures and their dynamics by employing high-resolution Fourier light-field microscopy. We demonstrated this method by capturing lysosomal autofluorescence in fibroblasts and HeLa cells. Additionally, we conducted multicolor imaging to simultaneously observe lysosomal autofluorescence and fluorescently-labeled organelles such as lysosomes and mitochondria. We further analyzed the data to quantify the interactions between lysosomes and mitochondria. This research lays the foundation for future exploration of native cellular states and functions in three-dimensional environments, effectively reducing photodamage and eliminating the necessity for exogenous labels.
more » « less- PAR ID:
- 10434849
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Biomedical Optics Express
- Volume:
- 14
- Issue:
- 8
- ISSN:
- 2156-7085
- Format(s):
- Medium: X Size: Article No. 4237
- Size(s):
- Article No. 4237
- Sponsoring Org:
- National Science Foundation
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