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Updated: Feb 8, 2026

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

Published on: August 4, 2022

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Role of the MAPK/cJun NH2-terminal kinase signaling pathway in starvation-induced autophagy

Seda Avcioglu Barutcu1, Nomeda Girnius1, Santiago Vernia1

  • 1a Program in Molecular Medicine , University of Massachusetts Medical School , Worcester , MA , USA.

Autophagy
|June 29, 2018
PubMed

Insights

Mitogen-activated protein kinase 8 (MAPK8/JNK1) and MAPK9 are not required for starvation-induced autophagy. These findings suggest the role of MAPK8/9 in autophagy is context-dependent and complex.

Area of Science:

  • Cellular Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Autophagy is crucial for cellular homeostasis and survival under stress.
  • Mechanistic target of rapamycin (MTOR) is a known regulator of starvation-induced autophagy.
  • Recent studies suggested a role for the MAPK8/JNK1 pathway in autophagy.

Purpose of the Study:

  • To investigate the role of MAPK8/JNK1 and MAPK9/JNK2 in starvation-induced autophagy.
  • To determine if MAPK8/9 signaling is essential for autophagy triggered by MTOR inhibition.

Main Methods:

  • Experiments were conducted using murine fibroblasts and epithelial cells.
  • Autophagy induction was achieved through starvation and MTOR inhibition.
  • The requirement of MAPK8/JNK1 and MAPK9/JNK2 was assessed in these conditions.

Main Results:

  • MAPK8/JNK1 and MAPK9/JNK2 were found to be non-essential for autophagy induced by starvation.
  • These kinases were also not required for autophagy resulting from MTOR inhibition.
  • The data indicate MAPK8/9 does not play a required role in starvation-induced autophagy.

Conclusions:

  • MAPK8/JNK1 and MAPK9/JNK2 are not required for starvation-induced autophagy in the studied cell types.
  • The previously implicated role of MAPK8/9 in autophagy may be context-specific.
  • The precise function of MAPK8/9 in autophagy warrants further investigation due to its complexity.
Keywords:
Epithelial cellMAPK8MAPK9MTORfibroblasthepatocyte

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