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Updated: Aug 15, 2026
09:31
Inducible, Cell Type-Specific Expression in Arabidopsis thaliana Through LhGR-Mediated Trans-Activation
Published on: April 19, 2019
Specific function of a plastid sigma factor for ndhF gene transcription
Jean-Jacques Favory1, Masanori Kobayshi, Kan Tanaka
1Laboratoire Plastes et différenciation cellulaire, Université Joseph Fourier and Centre National de la Recherche Scientifique, B.P. 53, 38041 Grenoble, France.
Nucleic Acids Research
|October 26, 2005
Summary
Researchers identified SIG4, a plastid sigma factor, crucial for regulating the NAD(P)H dehydrogenase (NDH) complex. This finding reveals transcriptional control of NDH activity by SIG4 in plants.
Area of Science:
- Plant Molecular Biology
- Photosynthesis Research
- Gene Regulation
Background:
- Plastid transcriptional regulation is complex, involving multiple RNA polymerases and regulatory proteins.
- Sigma factors are key regulators of plastid-encoded RNA polymerase (PEP) activity.
Purpose of the Study:
- To characterize the function of SIG4, a specific sigma factor involved in plastid transcription.
- To investigate the role of SIG4 in the regulation of the NAD(P)H dehydrogenase (NDH) complex.
Main Methods:
- Characterization of an Arabidopsis T-DNA insertion mutant for the SIG4 gene.
- Analysis of ndhF gene transcription levels.
- Assessment of NDH complex activity through subunit absence and chlorophyll fluorescence transients.
Main Results:
- The SIG4 mutant exhibited significantly reduced transcription of the plastid ndhF gene.
- A strong down-regulation of plastid NAD(P)H dehydrogenase (NDH) activity was observed in the mutant.
- Absence of NDHH subunit and altered chlorophyll fluorescence transients confirmed the reduced NDH activity.
Conclusions:
- Plastid NAD(P)H dehydrogenase (NDH) activity is regulated at the transcriptional level.
- The plastid sigma factor SIG4 specifically controls the transcription of the ndhF gene, thereby regulating NDH activity.
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