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Updated: Jun 17, 2026
09:13
In vivo Interrogation of Central Nervous System Translatome by Polyribosome Fractionation
Published on: April 30, 2014
Transcriptome and proteome exploration to model translation efficiency and protein stability in Lactococcus lactis
Clémentine Dressaire1, Christophe Gitton, Pascal Loubière
1Université de Toulouse, INSA, UPS, INP, LISBP, Toulouse, France.
Plos Computational Biology
|December 19, 2009
Summary
This study reveals that protein levels in cells are influenced by translation efficiency and degradation rates, which vary with growth conditions. These factors are crucial for understanding bacterial protein regulation and can be estimated using a novel modeling approach.
Area of Science:
- Molecular Biology
- Systems Biology
- Microbiology
Background:
- Cellular protein levels are critical for biological functions.
- Understanding the regulation of protein homeostasis is essential.
- Previous studies lacked methods to accurately estimate protein translation and degradation rates in bacteria.
Purpose of the Study:
- To analyze parameters influencing cellular protein levels.
- To estimate translation efficiencies and protein degradation rates.
- To investigate the biological significance of these parameters.
Main Methods:
- Genome-scale analysis of Lactococcus lactis.
- Continuous culture at different growth rates.
- Proteomic and transcriptomic data integration.
- Data fitting modeling approach to estimate rates.
Main Results:
- mRNA-to-protein ratios varied significantly across proteins and growth conditions.
- Translation efficiencies and degradation rates differed substantially between proteins.
- These rates were inversely proportional to growth rate, with higher translation efficiency at lower growth rates and increased protein degradation.
- Estimated protein half-lives ranged from 23 to 224 minutes.
- Complex regulation of intracellular protein levels was observed.
Conclusions:
- A novel modeling approach successfully estimated bacterial translation efficiencies and degradation rates.
- Protein degradation plays a significant role, especially at low growth rates.
- The method is applicable to other microorganisms and environments.
- This study provides insights into bacterial protein regulation dynamics.
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