Essential nucleoid proteins in early chloroplast development

Trends Plant Sci. 2013 Apr;18(4):186-94. doi: 10.1016/j.tplants.2012.11.003. Epub 2012 Dec 12.

Abstract

The plastid transcription machinery can be biochemically purified at different organisational levels as soluble RNA polymerase, transcriptionally active chromosome, or nucleoid. Recent proteomic studies have uncovered several novel proteins in these structures and functional genomic studies have indicated that a lack of many of these proteins results in chlorotic phenotypes of varying degree. The most severe cases exhibit complete albino phenotypes, which led to the conclusion that the proteins that were lacking had important regulatory roles in plastid gene expression and chloroplast development. In this opinion article, we propose an alternative model in which the structural establishment of a transcriptional subdomain within the nucleoid represents an early developmental bottleneck that leads to abortion of proper chloroplast biogenesis if disturbed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chloroplast Proteins / genetics
  • Chloroplast Proteins / metabolism*
  • Chloroplasts / genetics*
  • Chloroplasts / physiology
  • DNA, Chloroplast / genetics
  • DNA-Directed RNA Polymerases / genetics
  • DNA-Directed RNA Polymerases / metabolism
  • Gene Expression Regulation, Plant
  • Genome, Chloroplast / genetics*
  • Models, Biological
  • Phenotype
  • Transcription, Genetic

Substances

  • Chloroplast Proteins
  • DNA, Chloroplast
  • DNA-Directed RNA Polymerases