A study published in Nature Communications details what the researchers describe as a vicious cycle of toxic protein production set in motion by cell stress. The paper explains how a repeat element in the DNA of C9orf72, a gene associated with amyotrophic lateral sclerosis and frontotemporal dementia, is translated into a toxic protein in the face of viral infection, starvation, toxins or problems with misfolded proteins.
It's the latest study investigating repeat-associated non-AUG (RAN) translation in a host of neurological disorders that result from repeat mutations, including Huntington's disease, ataxia and myotonic dystrophy.
Authors find that C9RAN translation initiates through a cap- and eIF4A-dependent mechanism that utilizes a CUG start codon. C9RAN and CGG RAN are both selectively enhanced by integrated stress response (ISR) activation. ISR-enhanced RAN translation requires an eIF2α phosphorylation-dependent alteration in start codon fidelity. In parallel, both CGG and G4C2 repeats trigger phosphorylated-eIF2α-dependent stress granule formation and global translational suppression.
"Stressed cells typically stop making proteins, but in this case the stress actually activates more toxic protein production, creating a loop that potentially drives neuronal death," says first author.
"This suggests that outside stressors might influence when people get neurodegenerative diseases, even when the patient has a genetic mutation," adds senior author. "This may help explain when and why some people develop neurodegenerative diseases later in life."
The research addresses the most common cause of ALS, or Lou Gehrig's disease, leading to about 10 percent of cases. ALS is the most common motor neuron disease. The same repeat expansion mutation is also the most common genetic cause of frontotemporal dementia.
The researchers also found the same vicious cycle occurring at a second repeat mutation that causes a related neurodegenerative disease, fragile x-associated tremor/ataxia syndrome (FXTAS), suggesting this mechanism may be applicable to other repeat mutation disorders.
https://www.nature.com/articles/s41467-017-02200-0
Cell stress may enhance ALS!
- 1,873 views
- Added
Edited
Latest News
Metabolic rewiring promotes…
By newseditor
Posted 18 Apr
A drug to prevent flu-induc…
By newseditor
Posted 18 Apr
New origin of deep brain waves
By newseditor
Posted 17 Apr
Starving cells hijack prote…
By newseditor
Posted 17 Apr
Miniature battery-free epid…
By newseditor
Posted 17 Apr
Other Top Stories
Migraine-linked protein exhibits sex-specific pain effects
Read more
Potential biomarker for prion disease drugs
Read more
Altered GABA receptor trafficking and social behavior from protein…
Read more
Active life style helps in the recovery after spinal cord injury fa…
Read more
Dendritic spine changes implicated in remission behaviors after ket…
Read more
Protocols
MemPrep, a new technology f…
By newseditor
Posted 08 Apr
A tangible method to assess…
By newseditor
Posted 08 Apr
Stem cell-derived vessels-o…
By newseditor
Posted 06 Apr
Single-cell biclustering fo…
By newseditor
Posted 01 Apr
Modular dual-color BiAD sen…
By newseditor
Posted 31 Mar
Publications
How does the microbiota con…
By newseditor
Posted 18 Apr
The integrated stress respo…
By newseditor
Posted 18 Apr
The immunobiology of herpes…
By newseditor
Posted 17 Apr
Circulating microbiome DNA…
By newseditor
Posted 17 Apr
Spindle oscillations in com…
By newseditor
Posted 17 Apr
Presentations
Hydrogels in Drug Delivery
By newseditor
Posted 12 Apr
Lipids
By newseditor
Posted 31 Dec
Cell biology of carbohydrat…
By newseditor
Posted 29 Nov
RNA interference (RNAi)
By newseditor
Posted 23 Oct
RNA structure and functions
By newseditor
Posted 19 Oct
Posters
A chemical biology/modular…
By newseditor
Posted 22 Aug
Single-molecule covalent ma…
By newseditor
Posted 04 Jul
ASCO-2020-HEALTH SERVICES R…
By newseditor
Posted 23 Mar
ASCO-2020-HEAD AND NECK CANCER
By newseditor
Posted 23 Mar
ASCO-2020-GENITOURINARY CAN…
By newseditor
Posted 23 Mar