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Transcription initiation as a control point in plastid gene expression
Sujith Puthiyaveetil1, Steven D McKenzie1, Gilbert E Kayanja1
1Department of Biochemistry and Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA.
Biochimica Et Biophysica Acta. Gene Regulatory Mechanisms
|February 9, 2021
Summary
Gene expression in plastids is regulated at the transcriptional level, not just posttranscriptionally. Multiple RNA polymerases and sigma factors control plastid gene transcription, responding to environmental signals.
Area of Science:
- Plant Biology
- Molecular Biology
- Genetics
Background:
- Previous theories suggested gene expression control shifted entirely to posttranscriptional regulation in plastids.
- This viewpoint contrasted with existing observations on plastid gene transcription.
Purpose of the Study:
- To investigate the role of transcriptional regulation in plastid gene expression.
- To challenge the prevailing theory of posttranscriptional control dominance.
Main Methods:
- Analysis of RNA polymerases and sigma factors in plant and algal plastids.
- Investigation of regulatory mechanisms involving sigma factors, binding proteins, and phosphorylation.
- Identification of transcriptional regulators in plastids.
Main Results:
- Chloroplasts utilize multiple RNA polymerases with specific promoter preferences for coordinated RNA synthesis.
- Plastids possess diverse sigma factors crucial for transcription initiation.
- Sigma factor levels, protein interactions, and phosphorylation modulate transcriptional activity.
- Dedicated transcriptional regulators are present in plant and algal plastids.
Conclusions:
- Transcription initiation remains a critical control point for plastid gene expression.
- Plastid gene expression is influenced by developmental and environmental signals at the transcriptional level.
- The control of gene expression in plastids involves complex transcriptional regulatory strategies.
Keywords:
Chloroplast two-component systemsNuclear encoded polymerasePlastid encoded polymerasePlastid gene expressionSigma factorTranscription initiationMore Related Videos
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