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Literary linguistics: Open Access research in English language

Strathprints makes available Open Access scholarly outputs by English Studies at Strathclyde. Particular research specialisms include literary linguistics, the study of literary texts using techniques drawn from linguistics and cognitive science.

The team also demonstrates research expertise in Renaissance studies, researching Renaissance literature, the history of ideas and language and cultural history. English hosts the Centre for Literature, Culture & Place which explores literature and its relationships with geography, space, landscape, travel, architecture, and the environment.

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Molecular evolution in nonrecombining regions of the Drosophila melanogaster genome

Campos, José L and Charlesworth, Brian and Haddrill, Penelope R (2012) Molecular evolution in nonrecombining regions of the Drosophila melanogaster genome. Genome Biology and Evolution, 4 (3). pp. 278-288.

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Abstract

We study the evolutionary effects of reduced recombination on the Drosophila melanogaster genome, analyzing more than 200 new genes that lack crossing-over and employing a novel orthology search among species of the melanogaster subgroup. These genes are located in the heterochromatin of chromosomes other than the dot (fourth) chromosome. Noncrossover regions of the genome all exhibited an elevated level of evolutionary divergence from D. yakuba at nonsynonymous sites, lower codon usage bias, lower GC content in coding and noncoding regions, and longer introns. Levels of gene expression are similar for genes in regions with and without crossing-over, which rules out the possibility that the reduced level of adaptation that we detect is caused by relaxed selection due to lower levels of gene expression in the heterochromatin. The patterns observed are consistent with a reduction in the efficacy of selection in all regions of the genome of D. melanogaster that lack crossing-over, as a result of the effects of enhanced Hill-Robertson interference. However, we also detected differences among nonrecombining locations: The X chromosome seems to exhibit the weakest effects, whereas the fourth chromosome and the heterochromatic genes on the autosomes located most proximal to the centromere showed the largest effects. However, signatures of selection on both nonsynonymous mutations and on codon usage persist in all heterochromatic regions.