title: A DNA-polymerase-related reading frame (pol-r) in the mtDNA of Secale cereale.
abstract: Mitochondrial (mt)DNA of Secale cereale contains an open reading frame (pol-r), the potential translation product of which shows significant homology to the type-B DNA polymerase encoded by the S1 plasmid of Zea mays; it contains the highly-conserved domains IIa to V of family B polymerases. The pol-r ORF is transcribed, as proven by RT-PCR, but the transcript is not edited. Upstream of the putative start codon a potential promoter motif was detected, fitting well into the postulated consensus sequence of the transcription initiation regions of Z. mays and Triticum aestivum. The pol-r ORF occurs in mtDNA of the fertile rye variety "Halo" and the cytoplasmic male-sterile (CMS) line "Pampa". Both ORFs are almost identical, apart from the 3' terminus; pol-r from Halo can code for 289 amino acids, pol-r from Pampa for 312 amino acids. Based on codon usage and the lack of editing, pol-r is considered to be a "young" gene, probably introduced in the mtDNA of rye by recombination with an mt plasmid.
authors.affiliation: Institut für Botanik, Westfälische Wilhelms-Universität, Münster, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Dohmen
authors.forename: P
authors.initials: P
authors.lastname: Tudzynski
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics*; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D017343:Genes, Plant; D007246:Infertility / Q000235:genetics; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011401:Promoter Regions, Genetic; D017393:RNA Editing; D015183:Restriction Mapping; D012434:Secale / Q000201:enzymology* / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D014158:Transcription, Genetic; D014908:Triticum / Q000235:genetics; D003313:Zea mays / Q000235:genetics
chemical_list: D017931:DNA Primers; D004272:DNA, Mitochondrial; D004259:DNA-Directed DNA Polymerase