Related Experiment Video

Updated: Jan 11, 2026

Analyzing Starvation-Induced Autophagy in the Drosophila melanogaster Larval Fat Body
06:02

Analyzing Starvation-Induced Autophagy in the Drosophila melanogaster Larval Fat Body

Published on: August 4, 2022

2.9K

Endosomal microautophagy is activated by specific cellular stresses in trout hepatocytes

Emilio J Vélez1,2, Vincent Véron3, Jeanne Gouis3

  • 1INRAE, Université de Pau et des Pays de l'Adour, UMR1419 Nutrition Métabolisme et Aquaculture, 64310, Saint-Pée-sur-Nivelle, France. evelezve@ub.edu.

Scientific Reports
|November 10, 2025
PubMed

Insights

Endosomal microautophagy (eMI) selectively captures proteins in late endosomes. This study identifies an eMI-like pathway in trout cells, activated by specific cellular stresses, offering new insights into cellular homeostasis and stress responses.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Autophagy Research

Background:

  • Endosomal microautophagy (eMI) is a selective autophagic process.
  • eMI captures cytosolic proteins into late endosomes/multivesicular bodies (LE/MVB).
  • It shares similarities with chaperone-mediated autophagy (CMA) but utilizes different machinery.

Purpose of the Study:

  • To investigate the occurrence and triggers of eMI-like processes in non-mammalian models.
  • To understand the stimulus-specific induction of eMI.
  • To explore the interplay between eMI and CMA in cellular stress responses.

Main Methods:

  • Investigated eMI-like activity in rainbow trout hepatocytes.
  • Applied various cellular stress conditions: oxidative stress, high glucose, DNA damage, nutrient deprivation, and serum deprivation.
  • Analyzed protein targeting mechanisms involving HSC70, LAMP2A, and ESCRT machinery.

Main Results:

  • Identified an eMI-like process in rainbow trout hepatocytes.
  • This process was induced by oxidative stress, high glucose, DNA damage, and nutrient deprivation.
  • Serum deprivation did not trigger the eMI-like pathway, suggesting stimulus specificity.
  • eMI appears to play a compensatory role when CMA is impaired.

Conclusions:

  • eMI is a stimulus-specific pathway with a potential role in cellular homeostasis.
  • Rainbow trout hepatocytes provide a novel model for studying eMI and its interaction with CMA.
  • This research enhances understanding of cellular stress response mechanisms.

More Related Videos

A Fluorescence Microscopy Assay for Monitoring Mitophagy in the Yeast Saccharomyces cerevisiae10:27

A Fluorescence Microscopy Assay for Monitoring Mitophagy in the Yeast Saccharomyces cerevisiae

Published on: July 18, 2011

26.1K
Activating Autophagy by Aerobic Exercise in Mice08:44

Activating Autophagy by Aerobic Exercise in Mice

Published on: February 3, 2017

12.7K

Related Concept Videos

Autophagy01:27

Autophagy

Autophagy is a self-digesting process by which a cell protects itself from threats both within and outside the cell, ranging from abnormal proteins to invading bacteria. In this process, obsolete components of the cell and invading microbes are degraded by hydrolytic enzymes active in an acidic environment of the lysosomal lumen.
An autophagic pathway consists of a series of signaling events activated in response to diverse stress and physiological conditions such as food deprivation,...
5.6K
Autophagic Cell Death01:18

Autophagic Cell Death

Christian de Duve discovered “autophagy,” a process in which cellular components are engulfed by membrane-bound organelles called autophagosomes. The autophagosomes then fuse with lysosomes to digest the enclosed contents. Autophagy is generally activated in cells to prevent cell death. However, cell death is triggered when the damage is beyond repair.
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and...
4.3K
Delivery Pathways to the Lysosome01:36

Delivery Pathways to the Lysosome

Eukaryotic cells use different mechanisms to eliminate toxic waste obsolete and worn-out substances. Lysosomes play a pivotal role in this, and hence, these substances are carried to the lysosome from other parts of the cell and extracellular space through different pathways. The most elaborately studied pathways to the lysosome are the endocytic pathways.
Endocytosis
In endocytosis, the cell membrane takes up macromolecules and particles from the surrounding medium. Clathrin-mediated...
8.7K
Export of Misfolded Proteins out of the ER01:32

Export of Misfolded Proteins out of the ER

After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...
5.0K
mTOR Signaling and Cancer Progression03:03

mTOR Signaling and Cancer Progression

The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...
4.6K
The Unfolded Protein Response01:37

The Unfolded Protein Response

The ER is the hub of protein synthesis in a cell. It has robust systems to quality control protein folding and also for degradation of terminally misfolded proteins. Under normal conditions, a small proportion of misfolded proteins that cannot be salvaged need to be transported to the cytoplasm by the ER-associated degradation or ERAD pathways. However, if the ERAD cannot handle the misfolded proteins, the cell activates the unfolded protein response or UPR to adjust the protein folding...
6.2K