Evidence for regulatory function of nucleus-encoded factors on mRNA stabilization and translation in the chloroplast.

ABSTRACT: A salient feature of organelle gene expression is the requirement for nucleus-encoded factors that act posttranscriptionally in a gene-specific manner. A central issue is to understand whether these factors are merely constitutive or have a regulatory function. In the unicellular alga Chlamydomonas reinhardtii, expression of the chloroplast petA gene-encoding cytochrome f, a major subunit of the cytochrome b(6)f complex, depends on two specific nucleus-encoded factors: MCA1, required for stable accumulation of the petA transcript, and TCA1, required for its translation. We cloned the TCA1 gene, encoding a pioneer protein, and transformed appropriate mutant strains with tagged versions of MCA1 and TCA1. In transformed strains expressing decreasing amounts of MCA1 or TCA1, the concentration

SUBMITTER: Raynaud C 

PROVIDER: S-EPMC1885633 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature