Ross Waller’s lab has published a paper, ‘Plastid translocon recycling in dinoflagellates demonstrates the portability of complex plastids between hosts’ in Current Biology in collaboration with colleagues in Ben Luisi’s lab and at the MRC Cambridge and the Cell and Plant Physiology Laboratory, Université Grenoble Alpes.
The paper identifies a mechanism by which chloroplasts for photosynthesis (plastid being the more generic term) can more easily be passed from one lineage to another than we had previously through. Moreover, this process of serial transfer of plastids between organisms likely accounts for the majority of the diversity of photosynthetic organisms in the oceans. Researchers had previously thought that with each transfer two further membranes came to surround the plastid as a legacy of each uptake process. But Waller et al show that four membranes is where this accumulation typically stops, no matter how many times the plastid might be transferred. This means that many organisms that were thought to have secondary plastids (the product of only two sequential uptakes) should now be considered to potentially have gained their plastids as a product of more such transfers. In effect, photosynthesis has likely been shared around eukaryotes much more than previously thought.
The Waller lab worked with Ben Luisi’s lab to use cryoET of thin sectioned frozen cells to determine how many membranes surround this plastid which was a key part of the interpretation in the paper. It was the first application of tomography on thinned frozen samples in the Department facility.