  As the question of the origins of eukaryotes comes closer to an answer, the
interactions between the archaeal ancestor to eukaryotes and environmental,
molecular, bacterial, other influences and symbionts have become increasingly
relevant. Various studies have pointed towards the Lokiarchaeota as a close
archaeal relative to the eukarya. A study by Imachi et al., published in early
2020, was able to decipher the proteome and genome of the Loki and reported an
entirely new model for eukaryogenesis due to its findings, thus shifting
research of eukaryogenesis away from models focusing on endocytosis and the
rapid acquisition of the alphaproteobacteria that would become the
mitochondria. Imachi and colleagues proposed that ancestors of the Loki lived
symbiotically with other prokaryotes due to its shape, and facilitated
molecular transfer between the symbionts as well as the membrane manipulation
necessary to allow such transfer, before acquiring a proto-mitochondria over
time. This paper will lay out the history of endosymbiosis and the prevailing
theory of endocytosis between archaea and alphaproteobacteria, and consolidates
the knowns and unknowns up to before the publication of Imachi et al. The
findings of their novel study will be discussed, and the knowns and unknowns
with respect to these new findings are re-consolidated. The two models of
eukaryogenesis are compared and, in moving forward with Imachi and colleagues
model, probable areas of research to further validate this approach are
discussed, as well as potential usage of research tools of other fields to
answer the persistent unknowns of how eukaryotes came to be.
