That is life: communicating RNA networks from viruses and cells in continuous interaction

Abstract

All the conserved detailed results of evolution stored in DNA must be read, transcribed, and translated via an RNA‐mediated process. This is required for the development and growth of each individual cell. Thus, all known living organisms fundamentally depend on these RNA‐mediated processes. In most cases, they are interconnected with other RNAs and their associated protein complexes and function in a strictly coordinated hierarchy of temporal and spatial steps (i.e., an RNA network). Clearly, all cellular life as we know it could not function without these key agents of DNA replication, namely rRNA, tRNA, and mRNA. Thus, any definition of life that lacks RNA functions and their networks misses an essential requirement for RNA agents that inherently regulate and coordinate (communicate to) cells, tissues, organs, and organisms. The precellular evolution of RNAs occurred at the core of the emergence of cellular life and the question remained of how both precellular and cellular levels are interconnected historically and functionally. RNA networks and RNA communication can interconnect these levels. With the reemergence of virology in evolution, it became clear that communicating viruses and subviral infectious genetic parasites are bridging these two levels by invading, integrating, coadapting, exapting, and recombining constituent parts in host genomes for cellular requirements in gene regulation and coordination aims. Therefore, a 21st century understanding of life is of an inherently social process based on communicating RNA networks, in which viruses and cells continuously interact.

Viroids-First—A Model for Life on Earth, Mars and Exoplanets

“…Here we describe the view: "Viroids-first". We stress here that viroids, the virus-like elements or ribozymes, may have been the first biomolecules, a view that slightly differs from the "viruses-first" hypothesis described by Villareal and others [68][69][70][71]. There are alternative views to the one proposed here, such as "proteins-first" or "metabolism-first" [72][73][74][75][76][77][78][79][80][81] (Table 1).…”

“…Viruses-first Virus-like entities have evolved from complex molecules like nucleic acids and proteins [68][69][70][71]. Viruses contributed to the evolution of cellular life.…”

“…This might reflect their evolutionary age and long coevolution with all forms of life. Indeed, a recent definition of life on Earth integrates the important contribution of viruses and RNA networks [71].…”

What is Life?

“…However, in evolutionary periods, interacting RNA networks most propably predated viruses and cellular life (Root-Bernstein and Dillon, 1997;Witzany, 2011b;Root-Bernstein and Root-Bernstein, 2015;Demongeot and Seligmann, 2019) Here, we focus on the RNA strand level, which clearly shows infective and host-manipulating properties (Diener, 1989;Flores et al, 2012Flores et al, , 2014. This is coherent with the RNA world of RNA stem-loop groups and RNA group identities as result of biotic behavior represented by biological selection processes (Petrov et al, 2014;Ariza-Mateos et al, 2019;Villarreal and Witzany, 2019;Demongeot and Seligmann, 2020).…”

“…Most interestingly and unknown, the formerly termed RNA virus populations, quasispecies, are now recognized as highly interactive and cooperative agents (Villarreal and Witzany, 2013b). Virus communication demonstrates that quasispecies populations and subpopulations may cooperate and compete in parallel, dependent on the circumstantial context of host life (Villarreal and Witzany, 2019). Social interacting persistent viruses play important roles as host gene regulatory elements-in most cases represented by repetitive sequences-that may react to nearly every unexpected circumstance (Díaz-Muñoz et al, 2017;Sanjuán, 2018).…”