DNA-binding proteins in plant mitochondria: Implications for transcription

The structural complexity of plant mitochondrial genomes correlates with the variety of single-strand DNA-binding proteins found in plant mitochondria. Most of these are plant-specific and have roles in homologous recombination and genome maintenance. Mitochondrial nucleoids thus differ fundamentally between plants and yeast or animals, where the principal nucleoid protein is a DNA-packaging protein that binds double-stranded DNA. Major transcriptional cofactors identified in mitochondria of non-plant species are also seemingly absent from plants. This article reviews current knowledge on plant mitochondria! DNA-binding proteins and discusses that those may affect the accessibility and conformation of transcription start sites, thus functioning as transcriptional modulators without being dedicated transcription factors. (C) 2014 Elsevier B.V. and Mitochondria Research Society. All rights reserved.