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Recombineering Homologous Recombination Constructs in Drosophila
Published on: July 13, 2013
Two Dobzhansky-Muller genes interact to cause hybrid lethality in Drosophila
Nicholas J Brideau1, Heather A Flores, Jun Wang
1Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
Abstract:
The Dobzhansky-Muller model proposes that hybrid incompatibilities are caused by the interaction between genes that have functionally diverged in the respective hybridizing species. Here, we show that Lethal hybrid rescue (Lhr) has functionally diverged in Drosophila simulans and interacts with Hybrid male rescue (Hmr), which has functionally diverged in D. melanogaster, to cause lethality in F1 hybrid males. LHR localizes to heterochromatic regions of the genome and has diverged extensively in sequence between these species in a manner consistent with positive selection. Rapidly evolving heterochromatic DNA sequences may be driving the evolution of this incompatibility gene.
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