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Automated Imaging and Analysis for the Quantification of Fluorescently Labeled Macropinosomes
Published on: August 24, 2021
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MicroRNAs-103/107 coordinately regulate macropinocytosis and autophagy
Jong Kook Park1, Han Peng1, Julia Katsnelson2
1Department of Dermatology, Northwestern University, Chicago, IL 60611.
The Journal of Cell Biology
|November 23, 2016
Summary
The microRNA-103/107 family suppresses fluid uptake via macropinocytosis and preserves the final stages of autophagy. This regulation is crucial for maintaining the stem cell-enriched limbal epithelium.
Area of Science:
- Cell Biology
- Molecular Biology
- Stem Cell Biology
Background:
- Macropinocytosis and autophagy are cellular processes involving vesicle formation and turnover.
- While early stages are understood, the regulation of end-stage macropinocytosis and autophagy remains unclear.
- The microRNA-103/107 family is highly expressed in limbal epithelium stem cells.
Purpose of the Study:
- To investigate the role of the microRNA-103/107 family in regulating macropinocytosis and autophagy.
- To elucidate the molecular mechanisms by which microRNA-103/107 control these processes.
- To understand the contribution of microRNA-103/107 to limbal epithelium maintenance.
Main Methods:
- Investigated the effects of microRNA-103/107 loss on cellular processes.
- Analyzed the regulation of signaling pathways including Src, Ras, Ankfy1, diacylglycerol/protein kinase C, and cyclin-dependent kinase 5.
- Examined the role of dynamin in vacuole clearance.
Main Results:
- Loss of microRNA-103/107 leads to dysregulated macropinocytosis and vacuole accumulation.
- Up-regulation of Src, Ras, and Ankfy1 are implicated in macropinocytosis dysregulation.
- MicroRNA-103/107 ensures proper end-stage autophagy by regulating specific signaling pathways essential for dynamin-mediated vacuole clearance.
Conclusions:
- MicroRNA-103/107 coordinately suppresses macropinocytosis and preserves end-stage autophagy.
- These microRNAs play a vital role in maintaining the stem cell-enriched limbal epithelium.
- The findings reveal a novel function for microRNA-103/107 in cellular homeostasis.
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