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ALTERNATIVE HYPOTHESIS. "Could Eukaryotic Sex be a Further Symbiogenic Effect due to the (Proto)Mitochondrion?" https://lnkd.in/deZ8DED View in LinkedIn

NON-CODING DNA CONVERSION. "A number of de novo genes originating from non-coding regions have been identified in Drosophila, humans, primates, murine rodents, Protozoa, yeast, rice as well as virus." https://lnkd.in/dvpUaYF View in LinkedIn

PLANET EARTH OXYGEN. "Eukaryotes only arose ∼1.6–2.1 billion years ago, tellingly after the Great Oxygenation Event 2.3 billion years ago, compared with the “rapid” evolution of prokaryotes, which are more than 3.5 billion years old." https://lnkd.in/deZ8DED View in LinkedIn

NEW FUNCTIONS. "Divergence in alternative splicing patterns between duplicate genes can generate distinct transcripts that produce noncoding RNAs or polypeptides with slightly or entirely different functions and rapidly alter duplicate gene structures and functions." https://lnkd.in/dvpUaYF View in LinkedIn

OXIDATIVE DAMAGE THEORY. "Did Meiotic Sex Evolve in Response to Reactive Oxygen Species? Lately, more and more research has uncovered links between stress conditions, such as Reactive Oxygen Species formation, and meiotic sex. One essential question of course remains: where did the Reactive Oxygen Species that possibly gave rise to the invention of meiotic sex in eukaryotes come from?" https://lnkd.in/deZ8DED View in LinkedIn

ASPERGILLUS PARASEXUAL CYCLES. “More rapidly growing variants readily arise from homozygous diploids, but not from the corresponding haploid “parent,” and they are then reduced to a haploid state. The faster growing variants prove to harbor multiple recessive alleles, reciprocally epistatic, that together are beneficial but individually are deleterious, and thus they can only accumulate in the diploid and then be released during parasexual genome reduction. These studies illustrate the capacity of haploid-diploid-haploid parasexual cycles to generate genotypic and phenotypic diversity de novo.” http://cshperspectives.cshlp.org/content/6/3/a016154.full View in LinkedIn

THE SHELTERED DIPLOID. “Aspergillus has a bona fide homothallic (selfing) sexual cycle, but also undergoes a parasexual cycle under laboratory conditions: Diploids are generated from haploid progenitors by hyphal fusion and the resulting diploid then loses chromosomes randomly to return to the haploid state. Recent studies have shown that this parasexual cycle provides access to a sheltered diploid state that can serve as a capacitor for evolution.” https://lnkd.in/ebVhXPf View in LinkedIn

TWO PHASES. “As one must walk before one can run, the fusion of cells may have led to early parasexual cycles from which true meiotic sexual cycles evolved at a later time.” https://lnkd.in/ebVhXPf View in LinkedIn

CUMBERSOME. “Increases in genome size/ploidy are expected to eventually become deleterious, however, one challenge being to organize a successful mitosis, another to regulate appropriate levels of gene expression. Hence, there would presumably have been positive selection for the acquisition of mechanisms to maintain copy number at a manageable size.” https://lnkd.in/ebVhXPf View in LinkedIn

FITNESS BENEFIT. “Another potential benefit of cell–cell fusion is hybrid fitness: If, as seems likely, there existed a variety of fledgling protoeukaryotes in the population that eventually gave rise to the last eukaryotic common ancestor, then their fusion would be expected to have yielded more gene-rich and occasionally more successful lineages.” http://cshperspectives.cshlp.org/content/6/3/a016154.full View in LinkedIn