Mapping of promoters for the nucleus-encoded plastid RNA polymerase (NEP) in the iojap maize mutant

Curr Genet. 1998 May;33(5):340-4. doi: 10.1007/s002940050345.


Plastid genes of higher plants may be transcribed by the plastid-encoded or the nucleus-encoded plastid RNA polymerases (PEP or NEP). The objective of this study was to identify NEP promoters in maize. To separate the NEP and PEP transcription activity, NEP promoter mapping was carried out in the iojap maize mutant which lacks the PEP. We report here that atpB, an ATPase subunit gene has promoters for both NEP and PEP, while clpP, a protease subunit gene, and the rpoB operon, encoding three PEP subunit genes, are exclusively transcribed from NEP promoters. The maize NEP promoters share sequence homology around the transcription initiation site, including the ATAGAATA/GAA loose consensus identified for tobacco, suggesting conservation of the NEP transcription machinery between monocots and dicots.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Base Sequence
  • Cell Nucleus / metabolism
  • Chromosome Mapping
  • Conserved Sequence
  • DNA-Directed RNA Polymerases / biosynthesis
  • DNA-Directed RNA Polymerases / genetics*
  • Molecular Sequence Data
  • Mutation*
  • Plants / genetics
  • Plastids / enzymology
  • Promoter Regions, Genetic*
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid
  • Transcription, Genetic
  • Zea mays / enzymology*
  • Zea mays / genetics*


  • DNA-Directed RNA Polymerases