Related Experiment Video
Updated: Jun 30, 2026
08:47
Monitoring eIF4F Assembly by Measuring eIF4E-eIF4G Interaction in Live Cells
Published on: May 1, 2020
Remodeling of mRNA by eIF4F in human translation initiation
Carlos Alvarado1, Christopher P Lapointe2, Jinfan Wang3
1Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA.
Biorxiv : the Preprint Server for Biology
|June 29, 2026
Summary
This study reveals how the eIF4F complex activates mRNA for translation initiation. It shows eIF4F binding is rate-limiting, followed by ATP-dependent mRNA extension, enabling ribosome loading.
Area of Science:
- Molecular Biology
- Biochemistry
- Genetics
Background:
- Translation initiation is crucial for protein synthesis.
- The role of the eIF4F complex in mRNA activation is not fully understood.
- Understanding this process is key to regulating gene expression.
Purpose of the Study:
- To elucidate the mechanism of mRNA activation by the eIF4F complex.
- To characterize the roles of individual eIFs in this process.
- To establish a kinetic framework for early translation initiation.
Main Methods:
- Utilized multi-perspective real-time single-molecule assays.
- Observed mRNA-eIF4F binding, mRNA conformational remodeling, and 40S ribosomal subunit loading.
- Investigated the impact of mRNA features like the 5' cap and secondary structures.
Main Results:
- Identified distinct roles for eIFs 4E, 4G, and 4B in eIF4F association and eIF4A binding.
- Demonstrated that eIF4F binding is the rate-limiting step in mRNA activation.
- Showed that mRNA conformational extension is ATP-dependent and required for 43S PIC loading.
Conclusions:
- Established a kinetic and mechanistic framework for early translation initiation.
- Highlighted the importance of mRNA features in regulating ribosome loading.
- Provided direct mechanistic insights into a fundamental process of gene expression.
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