Comparative dynamic transcriptome analysis (cDTA) reveals mutual feedback between mRNA synthesis and degradation.
Mai Sun1, Björn Schwalb, Daniel Schulz
1Gene Center Munich and Department of Biochemistry, Center for Integrated Protein Science CIPSM, Ludwig-Maximilians-Universität München, Munich, Germany.
Genome Research
|April 3, 2012
Summary
Comparative dynamic transcriptome analysis (cDTA) reveals how eukaryotic cells regulate mRNA levels. This method shows that mRNA synthesis and decay are linked, allowing cells to buffer changes.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Eukaryotic mRNA metabolism is crucial for gene expression.
- Conventional methods for mRNA turnover analysis are often perturbing.
- Understanding mRNA synthesis and decay dynamics is essential for cellular regulation.
Purpose of the Study:
- To develop a nonperturbing method for monitoring eukaryotic mRNA metabolism.
- To quantify absolute rates of mRNA synthesis and decay.
- To investigate the relationship between mRNA synthesis and decay in yeast.
Main Methods:
- Comparative dynamic transcriptome analysis (cDTA) was developed.
- Nonperturbing metabolic labeling was employed.
- Saccharomyces cerevisiae (Sc) and Schizosaccharomyces pombe (Sp) were used as internal standards.
Main Results:
- cDTA provides absolute mRNA synthesis and decay rates.
- Orthologous transcripts in Sc and Sp have similar synthesis but different decay rates.
- Eukaryotic cells can buffer mRNA levels through feedback mechanisms between synthesis and degradation.
Conclusions:
- cDTA is a novel method for analyzing mRNA metabolism.
- Distinct mRNA decay rates contribute to similar mRNA concentrations in different yeast species.
- A feedback loop likely exists between mRNA synthesis and degradation in eukaryotes.
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