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Specific function of a plastid sigma factor for ndhF gene transcription.

ABSTRACT: The complexity of the plastid transcriptional apparatus (two or three different RNA polymerases and numerous regulatory proteins) makes it very difficult to attribute specific function(s) to its individual components. We have characterized an Arabidopsis T-DNA insertion line disrupting the nuclear gene coding for one of the six plastid sigma factors (SIG4) that regulate the activity of the plastid-encoded RNA polymerase PEP. This mutant shows a specific diminution of transcription of the plastid ndhF gene, coding for a subunit of the plastid NDH [NAD(P)H dehydrogenase] complex. The absence of another NDH subunit, i.e. NDHH, and the absence of a chlorophyll fluorescence transient previously attributed to the activity of the plastid NDH complex indicate a strong down-regulation of NDH activity in the mutant plants. Results suggest that plastid NDH activity is regulated on the transcriptional level by an ndhF-specific plastid sigma factor, SIG4.

SUBMITTER: Favory JJ

PROVIDER: S-EPMC1266065 | biostudies-literature | 2005

REPOSITORIES: biostudies-literature

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Specific function of a plastid sigma factor for ndhF gene transcription.

Favory Jean-Jacques JJ Kobayshi Masanori M Tanaka Kan K Peltier Gilles G Kreis Martin M Valay Jean-Gabriel JG Lerbs-Mache Silva S

Nucleic acids research 20051020 18

The complexity of the plastid transcriptional apparatus (two or three different RNA polymerases and numerous regulatory proteins) makes it very difficult to attribute specific function(s) to its individual components. We have characterized an Arabidopsis T-DNA insertion line disrupting the nuclear gene coding for one of the six plastid sigma factors (SIG4) that regulate the activity of the plastid-encoded RNA polymerase PEP. This mutant shows a specific diminution of transcription of the plastid ...[more]

PMID: 16243785

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