Does the central dogma still stand?
Prions are agents of analog, protein conformation-based inheritance that can confer beneficial phenotypes to cells, especially under stress. Combined with genetic variation, prion-mediated inheritance can be channeled into prion-independent genomic inheritance. Latest screening shows that prions are common, at least in fungi. Thus, there is non-negligible flow of information from proteins to the genome in modern cells, in a direct violation of the Central Dogma of molecular biology. The prion-mediated heredity that violates the Central Dogma appears to be a specific, most radical manifestation of the widespread assimilation of protein (epigenetic) variation into genetic variation. The epigenetic variation precedes and facilitates genetic adaptation through a general 'look-ahead effect' of phenotypic mutations. This direction of the information flow is likely to be one of the important routes of environment-genome interaction and could substantially contribute to the evolution of complex adaptive traits.
National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA. koonin@ncbi.nlm.nih.gov
Eugene V
EV
Koonin
D000220:Adaptation, Biological; D000818:Animals; D044127:Epigenesis, Genetic; D019143:Evolution, Molecular; D014644:Genetic Variation; D040941:Heredity; D006801:Humans; D040582:Inheritance Patterns; D010641:Phenotype; D011328:Prions / Q000737:chemistry / Q000235:genetics*; D014176:Protein Biosynthesis; D012641:Selection, Genetic; D013312:Stress, Physiological
D011328:Prions