Related Experiment Video
Updated: Jun 13, 2026
09:10
siRNA Electroporation to Modulate Autophagy in Herpes Simplex Virus Type 1-Infected Monocyte-Derived Dendritic Cells
Published on: October 28, 2019
Jun proteins inhibit autophagy and induce cell death
1Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Autophagy
|April 21, 2010
Summary
Starvation triggers autophagy for survival, but nutrients inhibit it for proliferation. Immediate early genes JunB and c-Jun block autophagy, potentially causing apoptosis in starved cells.
Area of Science:
- Cellular biology
- Molecular mechanisms of cell survival and proliferation
Background:
- Autophagy is a cellular survival mechanism during starvation.
- Nutrient and serum supplementation typically inhibit autophagy and promote cell proliferation.
- Immediate early genes like JunB and c-Jun are induced by growth factors.
Purpose of the Study:
- To investigate the role of immediate early genes JunB and c-Jun in regulating autophagy.
- To understand how these genes influence cell fate under starvation and nutrient-rich conditions.
Main Methods:
- Analysis of gene expression patterns during starvation and nutrient supplementation.
- Investigating the inhibitory effect of JunB and c-Jun on the autophagic process.
- Assessing the impact of JunB deregulation on cell fate in starved cells.
Main Results:
- JunB and c-Jun were identified as inhibitors of autophagy.
- Serum and growth factor induction of JunB and c-Jun suppresses the autophagic response.
- Dysregulation of JunB during starvation promotes apoptosis.
Conclusions:
- Immediate early genes JunB and c-Jun play a critical role in suppressing autophagy.
- Aberrant expression of JunB can shift cell fate from survival (via autophagy) to apoptosis during starvation, highlighting a novel regulatory pathway.
Related Concept Videos
01:18Autophagic 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 pro-apoptotic...
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...
01:27Autophagy
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,...
An autophagic pathway consists of a series of signaling events activated in response to diverse stress and physiological conditions such as food deprivation,...
01:31The Intrinsic Apoptotic Pathway
Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
01:22Cellular Injury V: Apoptosis and Autophagy
Cells respond to damage and stress through highly coordinated processes that decide whether they survive or undergo controlled self-destruction. Two major pathways involved in this regulation are apoptosis, a type of programmed cell death, and autophagy, a survival mechanism that helps cells adapt to adverse conditions.ApoptosisApoptosis removes aged or injured cells to maintain tissue balance. During this process, the cell shrinks, chromatin condenses and fragments, and membrane-bound...
01:30Overview of Cell Death
Cell death is an essential process where the body gets rid of old or damaged cells. Cell proliferation and death need to be balanced, as an imbalance between the two may lead to cancer or autoimmune diseases.
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the 20th century...
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the 20th century...
01:17The Extrinsic Apoptotic Pathway
The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...