Origins of the machinery of recombination and sex

  title={Origins of the machinery of recombination and sex},
  author={T Cavalier-smith},
Mutation plays the primary role in evolution that Weismann mistakenly attributed to sex. Homologous recombination, as in sex, is important for population genetics – shuffling of minor variants, but relatively insignificant for large-scale evolution. Major evolutionary innovations depend much more on illegitimate recombination, which makes novel genes by gene duplication and by gene chimaerisation – essentially mutational forces. The machinery of recombination and sex evolved in two distinct… 

Elimination of altered karyotypes by sexual reproduction preserves species identity.

The reinterpretation of data from the literature strongly supports the hypothesis that the principal consequence of sexual reproduction is the reduction of drastic genetic diversity at the genome or chromosome level, resulting in the preservation of species identity rather than the provision of evolutionary diversity for future environmental challenges.

Uncoupling of sexual reproduction from homologous recombination in homozygous Oenothera species

The first linkage maps of homozygous, bivalent-forming Oenothera species are constructed and provide evidence that HR was exclusively confined to the chromosome ends of all linkage groups in this population.

Origin of the cell nucleus, mitosis and sex: roles of intracellular coevolution

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Complementation, genetic conflict, and the evolution of sex and recombination.

It is shown that asexual reproduction has a short-term disadvantage due to the loss of complementation of recessive deleterious mutations, which can overcome the 2-fold cost of meiosis in one or few generations.

Recombination as a driver of genome evolution : characterisation of biased gene conversion in mice

These findings are consistent with the hypothesis of a selective pressure restraining the intensity of the deleterious gBGC process at the population-scale: this would materialise through a multi-level compensation of the effective population size by the recombination rate, the length of conversion tracts and the transmission bias.

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  • A. SchurkoJ. Logsdon
  • Biology
    BioEssays : news and reviews in molecular, cellular and developmental biology
  • 2008
A "meiosis detection toolkit", a set of meiotic genes that represent the best markers for the presence of meiosis that will help to understand both meiotic gene evolution and the capacity for meiosis and sex in putative obligate asexuals.

Genomic Features of Parthenogenetic Animals

Not a single feature was systematically replicated across a majority of these transitions, suggesting that previously reported patterns were lineage-specific rather than illustrating the general consequences of parthenogenesis, and that only parthenogens of hybrid origin were characterized by high heterozygosity levels.

Origin of Sex Revisited

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The molecular basis of the evolution of sex.

Historical overview: Searching for replication help in all of the rec places

  • M. Cox
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2001
This overview attempts to trace the history of the search for recombination function in bacteria and their bacteriophages, as well as some of the parallel paths taken in eukaryotic recombination research.

Cell Cycles, Diplokaryosis and the Archezoan Origin of Sex

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It is found that competitive coexistence of an asexual diploid and sexual haploid is possible in spite of the fact that they are competing for a single resource (nucleotide building blocks), and it is indicated that transformation is probably not a diversifying force in bacterial evolution.

The bacterial replicative helicase DnaB evolved from a RecA duplication.

It is hypothesized that DnaB originated from a duplication of a RecA-like ancestor after the divergence of the bacteria from Archaea and eukaryotes, which indicates that the replication fork helicases in Bacteria and Archaea/Eukaryota have evolved independently.

Assembly of RecA-like recombinases: Distinct roles for mediator proteins in mitosis and meiosis

Immuno-double-staining experiments in Saccharomyces cerevisiae suggest that Rad51, the eukaryotic recombinase, can assemble at or near sites containing ssb (replication protein A, RPA) during the response to DNA damage, consistent with a need for mediator activity.

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