Polypeptides of DNA-dependent RNA polymerase of spinach chloroplasts: characterization by antibody-linked polymerase assay and determination of sites of synthesis

Lerbs, S.; Bräutigam, E.; Parthier, B.

doi:10.1002/j.1460-2075.1985.tb03834.x

Cited by 88 publications

(48 citation statements)

References 24 publications

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“…It has been repeatedly shown that the E. coli RNA polymerase and PEP have sufficient similarity to allow immunological cross-reaction (Lerbs et al, 1985;Lerbs, 1988;Iratni et al, 1994). So we have used two different antisera that have both been prepared against E. coli RNA polymerase (see ''Materials and Methods'').…”

Section: Rnas Encoding Nep and Pep Are Already Present In Dry Seeds Omentioning

confidence: 99%

Building Up of the Plastid Transcriptional Machinery during Germination and Early Plant Development

et al. 2006

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The plastid genome is transcribed by three different RNA polymerases, one is called plastid-encoded RNA polymerase (PEP) and two are called nucleus-encoded RNA polymerases (NEPs). PEP transcribes preferentially photosynthesis-related genes in mature chloroplasts while NEP transcribes preferentially housekeeping genes during early phases of plant development, and it was generally thought that during plastid differentiation the building up of the NEP transcription system precedes the building up of the PEP transcription system. We have now analyzed in detail the establishment of the two different transcription systems, NEP and PEP, during germination and early seedling development on the mRNA and protein level. Experiments have been performed with two different plant species, Arabidopsis (Arabidopsis thaliana) and spinach (Spinacia oleracea). Results show that the building up of the two different transcription systems is different in the two species. However, in both species NEP as well as PEP are already present in seeds, and results using Tagetin as a specific inhibitor of PEP activity demonstrate that PEP is important for efficient germination, i.e. PEP is already active in not yet photosynthetically active seed plastids.

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Section: Rnas Encoding Nep and Pep Are Already Present In Dry Seeds Omentioning

confidence: 99%

Building Up of the Plastid Transcriptional Machinery during Germination and Early Plant Development

et al. 2006

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“…The existence of two different types of RNA polymerases in plastids, which was suggested some years ago {Green-berg et al 1984;Lerbs et al 1988;Little and Hallick 1988}, seems to have been confirmed recently {Hess et al 1993; Lerbs-Mache 19931. There is evidence that one of the two enzymes is Escherichia coli-like (Lerbs et al 1985 and its subunits are encoded by the plastid rpo genes [Little and Hallick 1988;Hu and Bogorad 1990;Hu et al 19911. The importance of E. coil-like promoter elements on the plastid genome for transcription initiation has been shown by mutational analysis {Bradley and Gatenby 1985; Gruissem and Zurawski 1985a, b).…”

mentioning

confidence: 99%

Regulation of rDNA transcription in chloroplasts: promoter exclusion by constitutive repression.

Iratni¹,

Baeza²,

Андреева³

et al. 1994

Genes Dev.

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Spinach chloroplasts contain two types of RNA polymerases. One is multimeric and Escherichia coB-like. The other one is not E. coli-like and might represent a monomeric enzyme of 110 kD. The quantitative relation of the two polymerases changes during plant development. This raises the question, how are plastid genes transcribed that contain E. coli-like and non-E, coil-like promoter elements during developmental phases when both enzymes are present? Transcription of the spinach plastid rrn operon promoter is initiated at three sites: P1, PC, and P2. P1 and P2 are preceded by E. coli-like promoter elements that are recognized by E. coil RNA polymerase in vitro. However, in vivo, transcription starts exclusively at PC. We analyzed different promoter constructions using in vitro transcription and gel mobility-shift studies to understand why Pl and P2 are not used in vivo. Our results suggest that the sequence-specific DNA-binding factor CDF2 functions as a repressor for transcription initiation of the E. coli-like enzyme at PI and P2. We propose a mechanism of constitutive repression to keep the rrn operon in all developmental phases under the transcriptional control of the non-E, coli-like RNA polymerase.

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“…Spinach chloroplast RNA polymerase was found to contain seven prominent polypeptides, some of which were serologically related to subunits of the E. coli RNA polymerase (26). DNA sequences potentially encoding protein equivalents to the E. coli a and ,B subunits (rpoA and * Corresponding author.…”

mentioning

confidence: 99%

Evolutionary relationships among eubacteria, cyanobacteria, and chloroplasts: evidence from the rpoC1 gene of Anabaena sp. strain PCC 7120

Bergsland

Haselkorn

1991

J Bacteriol

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RNA polymerases of cyanobacteria contain a novel core subunit, y, which is absent from the RNA polymerases of other eubacteria. The genes encoding the three largest subunits of RNA polymerase, including y, have been isolated from the cyanobacterium Anabaena sp. strain PCC 7120. The genes are linked in the order rpoB, rpoCl, rpoC2 and encode the 1, y, and B' subunits, respectively. RNA polymerase in prokaryotes generally consists of a catalytic core of four subunits (W313'a2) and a dissociable sigma factor, which confers promoter specificity (7,16,44). The basic structure of the enzyme was believed to be the same in all eubacteria until the RNA polymerase of the filamentous cyanobacterium Anabaena sp. strain PCC 7120 was purified (37). The cyanobacterial core RNA polymerase was found to contain, in addition to a ,B, a ,3', and two a's, a novel core subunit of 70 kDa designated y, which is absent from the RNA polymerases of other eubacteria. Western immunoblotting with antiserum to -y has shown that a serologically related -y protein is present in over 30 different cyanobacteria, representing the five major taxonomic subgroups (4a, 36). Thus, the -y subunit is a common feature of cyanobacterial RNA polymerases.Anti--y serum cross-reacts with the Escherichia coli ' subunit protein, suggesting homology between these subunits (36). A region of DNA homologous to part of the E. coli gene encoding 3' (rpoC) has been isolated from another cyanobacterium, Nostoc commune UTEX 584 (47). Sequencing of this region showed that homology to E. coli rpoC is split between two linked genes, rpoCl and rpoC2, in the Nostoc DNA (47). The DNAs of several plant chloroplasts have likewise been found to contain regions of sequence homology with E. coli rpoC (19,20,30,38,39). In chloroplasts, the blocks of homology are also distributed between two genes, rpoCl and rpoC2. These genes are linked and are thought to encode the P' and ,B" subunits of chloroplast RNA polymerase, respectively.The exact subunit composition of chloroplast RNA polymerase is unclear. Spinach chloroplast RNA polymerase was found to contain seven prominent polypeptides, some of which were serologically related to subunits of the E. coli RNA polymerase (26). DNA sequences potentially encoding protein equivalents to the E. coli a and ,B subunits (rpoA and * Corresponding author. rpoB) have been found in chloroplast genomes, in addition to the rpoC homologs (19,20,30,39,40). In a few cases, these genes have been shown to be expressed in chloroplasts. The protein product of the rpoA gene has been identified in maize and pea chloroplasts (33,34 Isolation ofAnabaena sp. strain PCC 7120 RNA polymerase genes. The 2.8-and 2.3-kb EcoRI fragments containing parts of the E. coli rpoB and rpoC genes, respectively, were isolated from pGB218 (2), which was a gift from C. Squires. The fragments were labeled with [a-32P]dCTP (3,000 Ci/ mmol; New England Nuclear) by the random priming method (11) and used to probe a Southern blot of Anabaena sp. strain PCC 7120 chromosomal DNA digested ...

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Polypeptides of DNA-dependent RNA polymerase of spinach chloroplasts: characterization by antibody-linked polymerase assay and determination of sites of synthesis

Cited by 88 publications

References 24 publications

Building Up of the Plastid Transcriptional Machinery during Germination and Early Plant Development

Building Up of the Plastid Transcriptional Machinery during Germination and Early Plant Development

Regulation of rDNA transcription in chloroplasts: promoter exclusion by constitutive repression.

Evolutionary relationships among eubacteria, cyanobacteria, and chloroplasts: evidence from the rpoC1 gene of Anabaena sp. strain PCC 7120

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