High impact information on rpoB

• In vitro characterization of the tobacco rpoB promoter reveals a core sequence motif conserved between phage-type plastid and plant mitochondrial promoters [1].
• The editing efficiencies of both the corresponding rpoB and ndhF editing sites in the endogenous genes' transcripts and in several other genes' transcripts were reduced in the chloroplast transgenic plants [2].
• In order to further define cis sequences required for RNA editing, we investigated whether two editing sites present in maize rpoB mRNA would be recognized by the editing machinery of transformed tobacco chloroplasts [3].
• Promoters for NEP have been previously characterized in tobacco plants lacking PEP due to targeted deletion of rpoB (encoding the beta-subunit) from the plastid genome [4].
• In one case (rpoB, codon 206) the RNA sequence was conserved between the two species, but the mRNA is still not edited in rice [5].

Biological context of rpoB

• Using an in vivo transient assay system for gene expression in plastids, the 5'-flanking region of rpoB from Arabidopsis thaliana in plastids of cultured BY-2 tobacco cells was analyzed [6].
• Expression of transgene transcripts carrying the 27 nt sequence did not affect the editing extent of the endogenous rpoB transcripts, even though the chimeric transcripts were much more abundant than those of the endogenous gene [7].

Anatomical context of rpoB

• Deletion of rpoB reveals a second distinct transcription system in plastids of higher plants [8].

Associations of rpoB with chemical compounds

• Endogenous transcripts of rpoB, psbL and rps14, all of which contain common sequences S1, S2 and S3 5' to NTrpoB C473, NTpsbL C2 and NTrps14 C80, were less edited in transgenic plants that over-express transcripts from NTrpoB C473 transgenes [9].

References