Abstract
A stubborn question in early molecular evolution is how to sustain the "minimum" informational length required for the basic features of life with a putative low-copying fidelity RNA polymerase ribozyme. Proposals to circumvent the information crisis have primarily focused on networks of cooperative molecules or compartmentalization of non-cooperative unlinked templates, but success has been very limited so far. Lehman (2003) has recently suggested that recombination-a frequently ignored player in early evolution-could have been crucial to building up primeval genomes of sizable length. Here we investigate this claim by assuming (without loss of generality) that genes were already enclosed in a compartment (vesicle, protocell). The numerical results show a quite intricate interplay among mutation, recombination, and gene redundancy. Provided that the minimum number of gene copies per protocell was enough for recombination to recreate wild-type templates-but not too high to impose an unbearable burden of mutants-informational content could have increased by at least 25% by keeping the same mutational load as that for a population without recombination. However, the upper bound of informational length would still be far from the "minimal life" provisions.
Original language | English |
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Pages (from-to) | 507-519 |
Journal | Journal of Molecular Evolution |
Volume | 59 |
DOIs | |
Publication status | Published - 1 Oct 2004 |
Keywords
- Compartmentalization
- Error threshold
- Origin of life
- Recombination
- Stochastic corrector model
- Theoretical biology