Farias ST, Jose MV, Prosdocimi F. Is it possible that cells have had more than one origin? Biosystems. 2021 Apr;202:104371. doi: 10.1016/j.biosystems.2021.104371.
Farias ST, Jose MV, Prosdocimi F. Is it possible that cells have had more than one origin? Biosystems. 2021 Apr;202:104371. doi: 10.1016/j.biosystems.2021.104371.
Farias ST, Jose MV, Prosdocimi F. Is it possible that cells have had more than one origin? Biosystems. 2021 Apr;202:104371. doi: 10.1016/j.biosystems.2021.104371.
Farias ST, Jose MV, Prosdocimi F. Is it possible that cells have had more than one origin? Biosystems. 2021 Apr;202:104371. doi: 10.1016/j.biosystems.2021.104371.
Abstract
Cells occupy a prominent place in the history of life on planet Earth. The central role of cellular organization is observed by the fact that “cellular life” is often used as a synonym for life itself. Thus, most characteristics used to define cells overlap with the ones used to define life. Notwithstanding, new scenarios about the origin of life are bringing alternative views to describe how cells may have evolved from the open biological systems named progenotes. Here, using a logical and conceptual analysis, we re-evaluate the characteristics used to infer a single origin for cells. We argue that some evidences used to support cell monophyly, such as the presence of elements from both the translation mechanism and the universality of the genetic code, actually indicate a unique origin for all “biological systems”, a term used to define not only cells, but also virus and progenotes. Besides, we present evidence that at least two biochemical pathways as important as (i) DNA replication and (ii) lipid biosynthesis may not homologous between Bacteria and Archaea. The identities observed between the proteins involved in those pathways along representatives of these two ancestral Domains are too low to indicate common genic ancestry. Altogether these facts can be seen as an indication that cellular organization has possibly evolved two or more times and that LUCA (the Last Universal Common Ancestor) might not have existed as a cellular entity. Thus, we aim to consider the possibility that different strategies acquired by biological systems to exist, such as viral, bacterial and archaeal were originated independently from the evolution of different progenote populations.
Keywords
monophyly; progenotes; membrane evolution; origin of biological systems
Subject
Biology and Life Sciences, Anatomy and Physiology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
