Related Experiment Video
Updated: May 17, 2026
10:37
Toeprinting Analysis of Translation Initiation Complex Formation on Mammalian mRNAs
Published on: May 10, 2018
NMD: a multifaceted response to premature translational termination
Stephanie Kervestin1, Allan Jacobson
1Centre National de la Recherche Scientifique UPR9073, Université Paris Diderot Sorbonne Paris Cité, Institut de Biologie Physico-chimique, Paris, France.
Nature Reviews. Molecular Cell Biology
|October 18, 2012
Summary
Cellular quality control eliminates faulty messenger RNA (mRNA) through nonsense-mediated decay (NMD). NMD factors destabilize targeted mRNA with premature stop codons, preventing harmful protein production.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- Most messenger RNA (mRNA) molecules are translated into functional proteins.
- Cellular quality control pathways, including mRNA surveillance, eliminate aberrant mRNA.
- Nonsense-mediated decay (NMD) is a key mRNA surveillance pathway.
Purpose of the Study:
- To elucidate the multifaceted roles of factors involved in the nonsense-mediated decay (NMD) pathway.
- To understand how NMD regulates gene expression beyond mRNA degradation.
Main Methods:
- The abstract does not specify methods, but implies studies on mRNA surveillance and protein degradation pathways.
- Focuses on the functional analysis of NMD factors and their interactions.
Main Results:
- Premature translation termination triggers NMD by recruiting specific factors.
- These NMD factors destabilize targeted mRNAs.
- The same factors also repress translation, dissociate ribosomes, and promote truncated polypeptide degradation.
Conclusions:
- Nonsense-mediated decay (NMD) is a critical cellular quality control mechanism.
- NMD factors play diverse roles in regulating mRNA fate and protein synthesis.
- NMD may even influence transcription and splicing processes.
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02:27Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
02:27Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
02:31Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
02:31Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
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