Latest Paper: News and Views Article in Nature on ASGARD Archaebacteria

The first paper from the lab in 2017 [1] is a small comment on the discovery of more unusual archaebacterial genomes in sediment samples from a variety of locations around the world.

In this paper, I outlined the discovery and made a small number of observations about the work.

The ASGARD group are the closest non-eukaryotic relatives of eukaryotes (for now, of course, who knows if there are other groups to be discovered that might be more closely related to extant eukaryotes).

They have a number of gene families that might be seen as ‘prototypes’ or ‘very interesting relatives’ to gene families that we thought were only to be found in eukaryotes.

The very fundamental origins of some hitherto eukaryote-specific genes was probably in prokaryotic lineages.

The work firms up even more the fact that eukaryotes are not one of the deepest divisions of life, but was a merger of two prokaryotes.

What was not said in the News and Views article was that it now seems that the organisms that were involved in the initial merger that finally led to the eukaryote cell were in some way “exapted” (ready and waiting, if you like). This point was made previously by Akanni et al in 2015 [3].

Bottom line is that this is an interesting finding and I suspect there are more to come.

 

  • James.

 

REFERENCES

[1] McInerney, J.O. and O’Connell, M.J. (2017) Minding the gaps in cellular evolution. doi:10.1038/nature21113

[2] Zaremba-Niedzwiedzka, K., Caceres, E. F., Saw, J. H., Bäckström, D., Juzokaite, L., Vancaester, E., et al. (2017). Asgard archaea illuminate the origin of eukaryotic cellular complexity. Nature. http://doi.org/10.1038/nature21031

[3] Akanni, W.A., Siu-Ting, K., Creevey, C.J., McInerney, J.O., Wilkinson, M., Foster, P.G., and Pisani, D. (2015) Horizontal gene flow from Eubacteria to Archaebacteria and what it means for our understanding of eukaryogenesis. Philos Trans R Soc Lond B. Biol Sci. 370, 20140337. DOI: 10.1098/rstb.2014.0337