Format

Send to

Choose Destination
Plant Cell. 2013 Jan;25(1):167-86. doi: 10.1105/tpc.112.103051. Epub 2013 Jan 4.

Repression of essential chloroplast genes reveals new signaling pathways and regulatory feedback loops in chlamydomonas.

Author information

1
Department of Molecular Biology and Plant Biology, University of Geneva, 1211 Geneva, Switzerland.

Abstract

Although reverse genetics has been used to elucidate the function of numerous chloroplast proteins, the characterization of essential plastid genes and their role in chloroplast biogenesis and cell survival has not yet been achieved. Therefore, we developed a robust repressible chloroplast gene expression system in the unicellular alga Chlamydomonas reinhardtii based mainly on a vitamin-repressible riboswitch, and we used this system to study the role of two essential chloroplast genes: ribosomal protein S12 (rps12), encoding a plastid ribosomal protein, and rpoA, encoding the α-subunit of chloroplast bacterial-like RNA polymerase. Repression of either of these two genes leads to the arrest of cell growth, and it induces a response that involves changes in expression of nuclear genes implicated in chloroplast biogenesis, protein turnover, and stress. This response also leads to the overaccumulation of several plastid transcripts and reveals the existence of multiple negative regulatory feedback loops in the chloroplast gene circuitry.

PMID:
23292734
PMCID:
PMC3584532
DOI:
10.1105/tpc.112.103051
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center