![(a) A protocell driven by an autocatalytic cycle of small molecules that forms a metabolism. The bifurcating arrow indicates that two copies of C2 are formed by splitting a C4 molecule. The cycle as a whole is autocatalytic—the concentrations of C2, C3 and C4 all increase if there is a continued supply of C1. (b) A protocell in which templating of RNA oligomers occurs. The figure shows formation and melting of double strands and primer extension by addition of an activated nucleotide. The RNA process and the small-molecule cycle are conceptually similar. The cycle of nucleotide activation, templating and breakdown of oligomers is itself a metabolim [119].-- [Life]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/How-Strong.png?resize=1200%2C718&ssl=1)
[Life] The RNA World theory was proposed as a way to explain the origin of the DNA-RNA-Protein relationship found all current cells.
RNA world
![The RDP network of molecular cell biology. A schematic representation of the autocatalytic (RAF) set arrangement of components and processes constituting the biosynthesis network for the production of new RNA, DNA and protein (i.e., RDP) strands in living cells (gray background). The monomer units of RNA, DNA, and protein strands—ribonucleoside triphosphates (rNTPs), deoxyribonucleoside triphosphates (dNTPs), and amino acids—are considered to represent raw materials (“food”) -- [q-bio.MN]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/System.png?resize=1200%2C718&ssl=1)
Posted inGenomics, Proteomics, Bioinformatics
System-evolutionary View Of RNA Presence In Living Cells
[q-bio.MN] Our guiding question for this article was: How did RNA adjust its life when the RNA world era came to an end? RNA has its practical execution side in […]
Posted inGenomics, Proteomics, Bioinformatics
Pathways Of Early Evolution From The Perspectives Of A Riboreplisome — The Ultimate RNA Machine Of Life
[q-bio.PE] Translation of the genetic code into proteins is universal across life, with ribosomes serving as the ancient molecular machines enabling this information transformation. We propose that early replication and […]
Posted inOrigin & Evolution of Life
Computational Modeling Of An RNA-peptide World
[biorxiv.org] Emergence and evolution of functional RNA and protein structures are the central problems for understanding the origin of life.
Posted inOrigin & Evolution of Life
New Study Pinpoints When Early Earth May Have Become Ready for Life’s Chemistry
[PSI] Conditions on the early Earth may have become stable enough to sustain the chemistry associated with the origins of life around 4.33 billion years ago, according to new research […]
![A symbiotic scenario for co-evolution of the ribosome and the replicase. Two variations of the scenario are depicted, whereby the peptidyltransferase center (PTC) and the replicase (REP) ribozymes are encoded by distinct (A) or the same (B) RNA molecule. The figure depicts three major stages of cellular evolution from the primordial RNA world (left) to the intermediate RNA-protein world (center) and the last universal cellular ancestor (LUCA, right). The major events occurring during each stage are briefly described in the corresponding information boxes at the bottom of the figure. -- [q-bio.PE]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/The-selfish.png?resize=1200%2C712&ssl=1)
Posted inGenomics, Proteomics, Bioinformatics
The Selfish Ribosome
[q-bio.PE]. The ribosome is responsible for protein synthesis in all cells, and is the largest energy consumer in the cell.
Posted inOrigin & Evolution of Life
RNA Droplets May Have Helped Start life on Earth
[University at Buffalo] It’s one of the origins of life’s chicken-or-the-egg problems: How could RNA have helped give rise to the first cells before there were cells to contain them?
![a) Biological evolution as stochastic optimization: Initially, wild-type cells x grow up a population. A mutant y grows up a population. The populations x and y compete. The winner (greater population) then fetches more resources. Fitness landscapes at the bottom show how the mutant is an experiment, where the winner decides the next step direction. b) Evolution annotated in terms of the Central Dogma: (Left, green) Wildtype starting point, NA encodes PR, which gives fitness F. (Top, red), Mutation in the blueprint NA, becoming NA’. (Red, green) both NA sequences grow up into populations. (Next) The populations compete for fitness. The winner, Fx now carries with it the winning sequence NAx and protein P Rx. -- [biorxiv.org]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/RNA-And-Proteins.png?resize=1200%2C720&ssl=1)
Posted inOrigin & Evolution of Life
RNA And Proteins Joined Up At The Origins Of Life: Persistence Is The Point
[biorxiv.org] What drove nucleic acids (NA) to associate with proteins (PR) at the Origins of Life? We reason from polymer physics and the Central Dogma (CD) that the fitness value […]
Posted inOrigin & Evolution of Life
How Early RNA-based Life May Have Repaired Its Genome
[University of Notre Dame] In most modern cells, DNA stores the genetic blueprint, and relies on proteins to replicate, repair and build from those blueprints. At the same time, proteins […]
Posted inBiochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life, Status Report
The RNA-First Fallacy: Conflating Evolutionary Ancestry with Prebiotic Primacy
The RNA-World hypothesis remains the most widely accepted framework in origins-of-life research, anchored in compelling biochemical evidence for RNA’s deep evolutionary ancestry. However, this viewpoint routinely extends beyond that and […]