![Kinetic processes of the strand-based RNA reactor model [12,13,15] and their projection onto motif kinetics. We consider heteropolymer strands consisting of the two complementary nucleotides X and Y, which could represent RNA or DNA nucleotides. (a) Schematic of the reactions within the strand reactor, including hybridization, dehybridization, templated ligation, and cleavage of oligonucleotide strands. Strands that are not covalently linked are separated by small gaps; four-nucleotide motifs, including 3′ or 5′ ends, are highlighted in green. In templated ligation, a 3′- and a 5′-end motif build a six-nucleotide motif that contains three overlapping four-nucleotide motifs. (b) At the level of sequence motifs, the kinetics are based on motif production and motif breakage reactions. In four-nucleotide motifs, strand ends are marked with 3′ or 5′, respectively. Templated ligation generates longer strands containing additional motifs, thereby contributing to motif production, while strand cleavage leads to to motif breakage. Hybridization is not explicitly represented in the motif-level description; instead, it is implicitly incorporated into the rate constants for motif production and breakage by assuming a hybridization-dehybridization equilibrium and deducing the corresponding dissociation constants. -- Physical Review E](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/03/Sequence-Motif-Dynamics.png?resize=1200%2C720&ssl=1)
In RNA world scenarios, pools of RNA oligomers form strongly interacting, dynamic systems, which enable molecular evolution.
DNA
Posted inAI - Data - Apps - Cybernetics, Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Origin & Evolution of Life, Status Report
Prebiotic Resource Constraints And The Origin Of Life: A Linear Logic Framework
The origin of life is a complex scientific problem demanding interdisciplinary approaches. We propose a Linear Logic (LL)-based computational framework to formally evaluate the feasibility of early biochemical pathways across […]
Posted inAnalog Studies, Arctic / Antarctic / Alpine, Away Teams & Field Reports, Extremeophiles and Extreme Environments, Genomics, Proteomics, Bioinformatics, Microbiology & Virology, Polar / Alpine Expeditions, Sample Return, Status Report
Genomic Adaptations Of Novel Halotolerant Bacteria From Extreme North Greenland
Peary Land, northern-most Greenland, is a cold desert region whose soil microbiome remains underexplored. This is the first study to explore the halotolerant soil microbiome of this region with culture-dependent […]
Posted inGenomics, Proteomics, Bioinformatics, Microbiology & Virology, Origin & Evolution of Life, Status Report
Asgard Archaeal Origin Of Microtubules
Eukaryotic cells change their shapes, actively segregate their DNA and contain membrane networks, facilitated by a complex cytoskeleton containing actin filaments, microtubules made from tubulin, and other components.
Posted inBiochemistry & Organic Chemistry, Extremeophiles and Extreme Environments, Genomics, Proteomics, Bioinformatics, Microbiology & Virology, Origin & Evolution of Life, Status Report
Archaeal G-Quadruplexes: A Novel Model for Understanding Unusual DNA/RNA Structures Across the Tree of Life
Archaea, a domain of microorganisms found in diverse environments including the human microbiome, represent the closest known prokaryotic relatives of eukaryotes.
Posted inAstrochemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Intelligence & Language, Origin & Evolution of Life, Panspermia, Status Report
Can The Timing Of The Origin Of Life Be Inferred From Trends In The Growth Of Organismal Complexity?
The origin of life embodies two fundamental questions: how and when did life begin? It is commonly conjectured that life began on Earth around 4 billion years ago.
Posted inBiogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Extremeophiles and Extreme Environments, Genomics, Proteomics, Bioinformatics, Habitable Zones, Microbiology & Virology, Press Release, Water/Hycean Worlds & Oceanography
One Of Earth’s Most Abundant Organisms Is Surprisingly Fragile
A group of ocean bacteria long considered perfectly adapted to life in nutrient-poor waters may be more vulnerable to environmental change than scientists realized.
Posted inAI - Data - Apps - Cybernetics, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Nanotechnology & SynBio, Press Release
AI Learns From The Tree Of Life To Support Rare Disease Diagnosis
Editor’s note: If we aspire to mount expeditions to new worlds and then embrace the task of characterizing and quantifying whatever life forms we find, the ability to map and […]
Posted inAstrochemistry, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Meteorites & Asteroids, Microbiology & Virology, Origin & Evolution of Life, Status Report
Heuristic Model On The Origin Of The Homochirality Of Life
Life demonstrates remarkable homochirality of its major building blocks: nucleic acids, amino acids, sugars, and phospholipids. We propose a mechanism that places the root of life homochirality in the formation […]
Posted inAstropharmacy / Biotechnology, Biochemistry & Organic Chemistry, Genomics, Proteomics, Bioinformatics, Microbiology & Virology, Nanotechnology & SynBio, Planetary Protection & Biosafety, Space Life Science, Space Stations, Status Report
Offworld Biotechnology Glovebox Operations: DNA Nano Therapeutics-Mission 2
Working in the space station’s Microgravity Science Glovebox, NASA astronaut Jonny Kim mixes proteins with Janus base nanomaterials, small molecules that mimic DNA base pairs, for DNA Nano Therapeutics-Mission 2.