Natural selection and immortality.
Genomes replicate while the host cells reproduce. I explore the reproduction/replication dialogue, based on a deep analysis of bacterial genomes, in relation to ageing. Making young structures from aged ones implies creating information. I revisit Information Theory, showing that the laws of physics permit de novo creation of information, provided an energy-dependent process preserving functional entities makes room for entities accumulating information. I identify explicit functions involved in the process and characterise some of their genes. I suggest that the energy source necessary to establish reproduction while replication is temporarily stopped could be the ubiquitous polyphosphates. Finally, I show that rather than maintain and repair the original individual, organisms tend to metamorphose into young ones, sometimes totally, sometimes progressively. This permits living systems to accumulate information over generations, but has the drawback, in multicellular organisms, to open the door for immortalisation, leading to cancer.
Danchin
Antoine
A
Genetics of Bacterial Genomes, CNRS URA2171, Institut Pasteur, Paris, France. antoine.danchin@normalesup.org
D000818:Animals; D001419:Bacteria / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D004261:DNA Replication; D004734:Energy Metabolism / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D015972:Gene Expression Regulation, Neoplastic; D016680:Genome, Bacterial; D006801:Humans; D008136:Longevity / Q000235:genetics*; D008957:Models, Genetic; D009369:Neoplasms / Q000235:genetics; D012098:Reproduction / Q000235:genetics; D012641:Selection, Genetic; D013997:Time Factors