Arf family GTPases are present in Asgard archaea

The evolution of eukaryotes is a fundamental event in the history of life. The closest prokaryotic lineage to eukaryotes, the Asgardarchaeota, encode proteins previously found only in eukaryotes, providing insight into their archaeal ancestor. Eukaryotic cells are characterized by endomembrane organelles, and the Arf family GTPases regulate organelle dynamics by recruiting effector proteins to membranes upon activation. The Arf family is ubiquitous among eukaryotes, but its origins remain elusive. We report a group of prokaryotic GTPases, the ArfRs, which are widely present in Asgardarchaeota. Phylogenetic analyses reveal that eukaryotic Arf family proteins arose from the ArfR group. Expression of representative Asgardarchaeota ArfR proteins in yeast and X-ray crystallographic studies demonstrate that ArfR GTPases possess the mechanism of membrane binding and structural features unique to Arf family proteins. Our results indicate that Arf family GTPases originated in the archaeal ancestor of eukaryotes, consistent with an endomembrane system evolving early in eukaryogenesis.Here we provided source data for phylogenetic analyses. For each analysis, four files are provided:*_unaligned.fasta - unaligned protein sequences, in some cases trimmed to the GTPase domain*_alignment.fasta - multiple sequence alignment (details about programs are provided in Supplementary information and Supplementary Table 5)*_trimmed_alignment.fasta - trimmed multiple sequence alignment, input for phylogenetic analysis (details about programs and settings are provided in Supplementary information and Supplementary Table 5)*_newick tree.treefile - phylogenetic tree in the Newick formatPreprint is available at bioRxiv: https://doi.org/10.1101/2024.02.28.582541