ABOVE: Moranella (M) inside Tremblaya (T) inside cells of the mealybug P. citri, with nucleus indicated with an N
MARK LADINSKY, CALIFORNIA INSTITUTE OF TECHNOLOGY
Mitochondria and plastids are organelles within eukaryotic cells that are thought to have derived from endosymbiotic bacteria and that, throughout evolution, have become entirely dependent on their hosts and vice versa. Many similar interdependent relationships appear to exist between bacteria and hosts—with evidence including the transfer of bacterial genes to the host genomes, for example—but proof that these genes function in pathways as complex and interconnected as that of, say, mitochondrial and nuclear genes has been formally lacking.
A report in Cell today (October 3) now provides such evidence, at least for one endosymbiont, the bacterium Moranella, and its host, the mealybug Planococcus citri. The study shows that the two work together to coordinate steps in the synthesis of the polymer peptidoglycan.
“It’s a necessary paper ...
