Evolution of linkage and genome expansion in protocells: The origin of chromosomes.

ABSTRACT: Chromosomes are likely to have assembled from unlinked genes in early evolution. Genetic linkage reduces the assortment load and intragenomic conflict in reproducing protocell models to the extent that chromosomes can go to fixation even if chromosomes suffer from a replicative disadvantage, relative to unlinked genes, proportional to their length. Here we numerically show that chromosomes spread within protocells even if recurrent deleterious mutations affecting replicating genes (as ribozymes) are considered. Dosage effect selects for optimal genomic composition within protocells that carries over to the genic composition of emerging chromosomes. Lacking an accurate segregation mechanism, protocells continue to benefit from the stochastic corrector principle (group selection of early rep

SUBMITTER: Szilagyi A 

PROVIDER: S-EPMC7665907 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature