Results of the vote for the best results for 2018

How an evolutionary conserved protein complex works in mitochondria, the powerhouses of eukaryotic cells, was published in the prestigious journal Current Biology. The editorial board selected the study as a featured article that is freely available to readers.  In the study, we identified the MICOS complex of trypanosomatids, whose analog in yeast and humans is responsible in the shaping cristae, the characteristic invagination of the mitochondrial inner membrane. We show that this function is conserved in the evolutionary diverged trypanosomes. This is important since it demonstrates how fundamental this complex is to eukaryotic cell biology. We also revealed unique aspects of the trypanosomatid complex. Most notable among these is that trypanosomatid MICOS is involved in import of proteins that are needed for populating cristae membranes with respiratory chain complexes. 

Kaurov I., Vancová M., Schimanski B., Cadena L.R., Heller J., Bílý T., Potěšil D., Eichenberger C., Bruce H., Oeljeklaus S., Warscheid B., Zdráhal Z., Schneider A., Lukeš J., Hashimi H. 2018: The diverged trypanosome MICOS complex as a hub for mitochondrial cristae shaping and protein import. Current Biology 28: 3393–3407. [IF=8.851]

2. Oborník + Horák et al. 2018: Fytotransferiny u řas

We explored evolutionary history of labile iron binding proteins ISIP2a and transferrins and showed that they share distant evolutionary homology. We conducted a comprehensive phylogenetic analysis of marine microeukaryotes, revealing both proteins to have a common origin in bacterial periplasmic binding proteins (PBP).  This novel clade of algal transferrin-like proteins, or phytotransferrins, is the third instance of transferrin-like proteins convergently evolving from anion-binding PBP and highlights the critical nature of the exogenous anion in coordinating high-affinity ferric iron binding. Though transferrin and phytotransferrin share ancient homology in phosphonate PBP, predating the prokaryotic/eukaryotic divergence, they are in fact functional analogs which independently acquired the ability to bind iron. The timing of these acquisitions (671–913 million years ago) is consistent with the radical biological innovations required to adapt to the changes in marine redox states and loss of dissolved iron which have been inferred for the Neoproterozoic. In transferrin, the switch in binding anion from phosphate to carbonate arose in Euryarchaea and was vertically transmitted to Eukaryota, while the chlorophyte acquisition of phytotransferrin plausibly occurred via endosymbiotic or horizontal gene transfer.  Both transferrin and phytotransferrin are simultaneously present in the genomes of deeply branching prasinophyte algae and in terrestrial algae; however, the absence of phytotransferrin from metazoa and the absence of transferrin from rhodophytes and all algae of secondary endosymbiotic origins suggests a pattern of early and selective gene loss. Most phytotransferrins are membrane anchored, a selective and functional advantage for single celled organisms living in a diffuse environment and a contributing factor in the dominance of phytotransferrin among marine microeukaryotes. 

McQuaid J.B., Kustka A.B.,  Oborník M.,  Horák A., Mccrow J., Karas B.J., Zheng H., Kindeberg T., Andersson A.J., Barbeau K.A., Allen A. 2018: Carbonate-sensitive phytotransferrin controls high-affinity iron uptake in diatoms. Nature 555: 534– 537. [IF=41.577]