Gene transfers from diverse bacteria compensate for reductive genome evolution in the chromatophore of Paulinella chromatophora
Abstract
Eukaryotic photosynthetic organelles (plastids) originated >1 billion y ago via the endosymbiosis of a β-cyanobacterium. The resulting proliferation of primary producers fundamentally changed our planet's history, allowing for the establishment of human populations. Early stages of plastid integration, however, remain poorly understood, including the role of horizontal gene transfer from nonendosymbiotic bacteria. Rules governing organellogenesis are difficult, if not impossible, to evaluate using the highly derived algal and plant systems. Insights into this issue are provided by the amoeba Paulinella chromatophora, which contains more recently established photosynthetic organelles of α-cyanobacterial origin. Here we show that the impact of Muller's ratchet that leads to endosymbiont genome reduction seems to drive the fixation of horizontally acquired "compensatory" bacterial genes in the host nuclear genome.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- October 2016
- DOI:
- 10.1073/pnas.1608016113
- Bibcode:
- 2016PNAS..11312214N