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Lindsey, A. R. I.

Publications and source records attributed to Lindsey, A. R. I..

2 recordsLinked to original sources

The Genomic Basis of Arthropod Diversity

BackgroundArthropods comprise the largest and most diverse phylum on Earth and play vital roles in nearly every ecosystem. Their diversity stems in part from variations on a conserved body plan, resulting from and recorded in adaptive changes in the genome. Dissection of the genomic record of sequence change enables broad questions regarding genome evolution to be addressed, even across hyper-diverse taxa within arthropods.\n\nResultsUsing 76 whole genome sequences representing 21 orders spanning more than 500 million years of arthropod evolution, we document changes in gene and protein domain content and provide temporal and phylogenetic context for interpreting these innovations. We identify many novel gene families that arose early in the evolution of arthropods and during the diversification of insects into modern orders. We reveal unexpected variation in patterns of DNA methylation across arthropods and examples of gene family and protein domain evolution coincident with the appearance of notable phenotypic and physiological adaptations such as flight, metamorphosis, sociality and chemoperception.\n\nConclusionsThese analyses demonstrate how large-scale comparative genomics can provide broad new insights into the genotype to phenotype map and generate testable hypotheses about the evolution of animal diversity.

genomics

Evolutionary genetics of cytoplasmic incompatibility genes cifA and cifB in prophage WO of Wolbachia

The bacterial endosymbiont Wolbachia manipulates arthropod reproduction to facilitate its maternal spread through populations. The most common manipulation is cytoplasmic incompatibility (CI): Wolbachia-infected males produce modified sperm that cause embryonic mortality, unless rescued by eggs harboring the same Wolbachia. The genes underlying CI, cifA and cifB, were recently identified in the eukaryotic association module of Wolbachias prophage WO. Here, we use transcriptomic and genomic approaches to address three important evolutionary facets of these genes. First, we assess whether or not cifA and cifB comprise a classic toxin-antitoxin operon, and show they do not form an operon in strain wMel. They coevolve but exhibit strikingly distinct expression across host development. Second, we provide new domain and functional predictions across homologs within Wolbachia, and we show amino acid sequences vary substantially across the genus. Lastly, we investigate conservation of cifA and cifB and find degradation and loss of the genes is common in strains that no longer induce CI. Taken together, we find no evidence for the operon hypothesis in wMel, provide functional annotations that broaden the potential mechanisms of CI induction, illuminate recurrent erosion of cifA and cifB in non-CI strains, and advance an understanding of the most widespread form of reproductive parasitism.

evolutionary biology