Extreme Life, Biospeology
and Astrobiology

The origin of life continues to represent one of the most complex and unresolved questions in modern science, necessitating the convergence of geochemistry, prebiotic chemistry, molecular biology, and evolutionary theory. This work explores the transformation from non-living chemical systems to the first biological forms, placing particular emphasis on the RNA world hypothesis and its connections to alternative models such as metabolism-first and lipid world scenarios. Available evidence supports the feasibility of RNA as an early biomolecule capable of fulfilling both informational and catalytic roles. Nonetheless, significant obstacles remain, including the prebiotic formation of nucleotides, the development of self-replicating ribozymes, and the achievement of high-fidelity replication under plausible environmental conditions. An increasing body of experimental and theoretical research points toward hybrid or co-evolutionary frameworks in which RNA, peptides, lipids, and protometabolic systems interacted from early stages and collectively facilitated the emergence of protocells. Comparative analyses of these competing models suggest that they are more appropriately interpreted as complementary elements within a multistage process, rather than as strictly competing hypotheses. Ongoing unresolved questions—such as the origin of the genetic code, the shift toward DNA–protein systems, and the coordination of replication with metabolism and compartmentalization—highlight the necessity for integrative, experimentally validated, system-level approaches. This study seeks to elucidate the current state of knowledge, identify major conceptual and experimental constraints, and underscore the critical role of integrative frameworks in advancing our understanding of the emergence of life.

This mini-review synthesizes current evidence regarding the effects of space radiation on cereal seeds, with emphasis on viability, germination, genetic integrity, and implications for extraterrestrial agriculture. Available data indicate that prolonged exposure to space radiation—particularly under low-shielding conditions—generally reduces seed viability and germination capacity, with marked interspecific variability, rice being more sensitive than barley or wheat. However, responses are heterogeneous, as some cereals exhibit enhanced germination under specific exposure scenarios, highlighting the complex interaction between radiation dose, quality, genotype, and environmental conditions. At the genomic level, space radiation induces DNA damage, chromosomal aberrations, and structural variation, supporting its application in mutation breeding programs. Orbital experiments aboard Mir and the International Space Station demonstrate that cereals can complete their life cycle in microgravity, although reproductive success is constrained by multiple interacting stressors, including atmospheric composition and system engineering limitations. For deep-space agriculture, current evidence remains insufficient, as low-Earth orbit (LEO) conditions do not fully replicate the radiation environment beyond Earth's magnetosphere. Emerging studies suggest that sustainable extraterrestrial crop production will require integrated strategies combining biological adaptation and physical radioprotection. Overall, space radiation represents both a risk factor for seed performance and a potential tool for crop improvement in future space-based agricultural systems.