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Updated: May 19, 2026
10:37
Toeprinting Analysis of Translation Initiation Complex Formation on Mammalian mRNAs
Published on: May 10, 2018
Probing translation initiation through ligand binding to the 5' mRNA coding region.
Joon-Jung Jo1, Joo-Hee Kim, Jong-Shik Shin
1Department of Biotechnology, Yonsei University, Shinchon-Dong 134, Seoul 120-749, South Korea.
Chembiochem : a European Journal of Chemical Biology
|August 29, 2012
Summary
Artificial riboswitches reveal that mRNA folding stability in the initial coding region is crucial for translation initiation in Escherichia coli. This finding highlights the importance of secondary structure for gene expression control.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Ribosome accessibility to the 5' coding region of messenger RNA (mRNA) is a critical determinant of translation initiation.
- The secondary structure of mRNA can influence its accessibility to the translational machinery.
- Understanding how mRNA secondary structure impacts translation is essential for deciphering gene expression regulation.
Purpose of the Study:
- To investigate the role of mRNA secondary structure in ribosome accessibility at the 5' coding region.
- To determine the specific regions of mRNA that influence translation initiation.
- To develop a tool for high-resolution probing of mRNA-ribosome interactions.
Main Methods:
- Construction of artificial intragenic riboswitches in Escherichia coli.
- Probing ribosome accessibility to the 5' mRNA coding region at three-base resolution.
- Analysis of the correlation between mRNA folding stability and translation efficiency.
Main Results:
- Artificial intragenic riboswitches were successfully constructed and utilized to probe ribosome accessibility.
- Translation initiation was found to be significantly affected by mRNA folding stability within the +1 to +15 nucleotide region of the coding sequence.
- Regions outside the +1 to +15 nt window showed minimal impact on the translation process.
Conclusions:
- mRNA secondary structure within the initial 15 nucleotides of the coding region plays a critical role in regulating translation initiation.
- The stability of this specific region directly impacts ribosome binding and the efficiency of translation.
- Artificial riboswitches provide a valuable tool for dissecting the mechanisms of translation control at a high resolution.
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