Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Disruption of plastid-encoded RNA polymerase genes in tobacco: expression of only a distinct set of genes is not based on selective transcription of the plastid chromosome

Disruption of plastid-encoded RNA polymerase genes in tobacco: expression of only a distinct set... Plastids of higher plants operate with at least two distinct DNA-dependent RNA polymerases, which are encoded in the organelle (PEP) and in the nucleus (NEP), respectively. Plastid run-on assays and Northern analyses were employed to analyse gene expression in tobacco mutant plastids lacking the PEP genes rpoA, rpoB or rpoC1. Hybridisation of run-on transcripts to restriction fragments representing the entire tobacco plastid chromosome, as well as to selected plastid gene-specific probes, shows that all parts of the plastid DNA are transcribed in rpo-deficient plastids. In comparison to wild-type chloroplasts, which are characterized by preferential transcription of photosynthesis-related genes in the light, mutant plastids exhibit a different transcription pattern with less pronounced differences in the hybridisation intensities between the individual genes. The analysis of steady-state transcript patterns and transcription rates of selected genes in both types of plastids demonstrates that differences in transcription rates are not necessarily paralleled by corresponding changes in transcript levels. The accumulation of large transcripts in the mutant plastids indicates that processing of primary transcripts may be impaired in the absence of PEP. These data suggest that, contrary to the prevailing view, much of the regulation of NEP-driven plastid gene expression in the rpo-deficient mutants is not based on differential promoter usage but is exerted at post-transcriptional levels. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Molecular Genetics and Genomics Springer Journals

Disruption of plastid-encoded RNA polymerase genes in tobacco: expression of only a distinct set of genes is not based on selective transcription of the plastid chromosome

Loading next page...
 
/lp/springer-journals/disruption-of-plastid-encoded-rna-polymerase-genes-in-tobacco-mTIEB5LlLm

References (0)

References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.

Publisher
Springer Journals
Copyright
Copyright © 2000 by Springer-Verlag Berlin Heidelberg
Subject
Life Sciences; Cell Biology; Biochemistry, general; Microbial Genetics and Genomics; Plant Genetics & Genomics; Animal Genetics and Genomics
ISSN
1617-4615
eISSN
1432-1874
DOI
10.1007/PL00008690
Publisher site
See Article on Publisher Site

Abstract

Plastids of higher plants operate with at least two distinct DNA-dependent RNA polymerases, which are encoded in the organelle (PEP) and in the nucleus (NEP), respectively. Plastid run-on assays and Northern analyses were employed to analyse gene expression in tobacco mutant plastids lacking the PEP genes rpoA, rpoB or rpoC1. Hybridisation of run-on transcripts to restriction fragments representing the entire tobacco plastid chromosome, as well as to selected plastid gene-specific probes, shows that all parts of the plastid DNA are transcribed in rpo-deficient plastids. In comparison to wild-type chloroplasts, which are characterized by preferential transcription of photosynthesis-related genes in the light, mutant plastids exhibit a different transcription pattern with less pronounced differences in the hybridisation intensities between the individual genes. The analysis of steady-state transcript patterns and transcription rates of selected genes in both types of plastids demonstrates that differences in transcription rates are not necessarily paralleled by corresponding changes in transcript levels. The accumulation of large transcripts in the mutant plastids indicates that processing of primary transcripts may be impaired in the absence of PEP. These data suggest that, contrary to the prevailing view, much of the regulation of NEP-driven plastid gene expression in the rpo-deficient mutants is not based on differential promoter usage but is exerted at post-transcriptional levels.

Journal

Molecular Genetics and GenomicsSpringer Journals

Published: Aug 27, 2000

There are no references for this article.