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Updated: Jul 4, 2026
10:37
Toeprinting Analysis of Translation Initiation Complex Formation on Mammalian mRNAs
Published on: May 10, 2018
Control of translation initiation: a model-based analysis from limited experimental data.
Richard J Dimelow1, Stephen J Wilkinson
1Manchester Interdisciplinary Biocentre, University of Manchester, Manchester M1 7DN, UK. r.dimelow@cyprotex.com
Journal of the Royal Society, Interface
|June 24, 2008
Summary
We developed a kinetic model for yeast translation initiation, identifying key control steps. Our analysis suggests either guanine nucleotide exchange or multifactor complex assembly significantly impacts translation rates.
Area of Science:
- Molecular Biology
- Biochemistry
- Systems Biology
Background:
- Translation initiation is a critical regulatory step in gene expression.
- Understanding the rate-limiting steps in translation initiation is crucial for comprehending cellular processes.
Purpose of the Study:
- To build a detailed kinetic model of translation initiation in yeast.
- To identify the flux-controlling steps within this pathway using limited experimental data.
Main Methods:
- Development of a detailed kinetic model for yeast translation initiation.
- Adaptation of an efficient parameter estimation method to fit model parameters to in vivo data.
- Utilizing random sampling of parameter space to explore uncertainties and generate diverse fitted parameter sets.
Main Results:
- Identified multiple plausible parameter sets fitting the experimental data.
- Characterized parameter sets using flux control analysis.
- Pinpointed two key reactions influencing translation initiation rate: guanine nucleotide exchange (eIF2/eIF2B) and multifactor complex assembly.
Conclusions:
- The rate of translation initiation in yeast is strongly influenced by either the guanine nucleotide exchange reaction or multifactor complex assembly.
- The presented modeling approach can enhance understanding of translation initiation pathways.
- This methodology can be applied to identify key system-level properties in other biochemical processes.
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