title: An Exon-Capture System for the Entire Class Ophiuroidea.
abstract: Exon-capture studies have typically been restricted to relatively shallow phylogenetic scales due primarily to hybridization constraints. Here, we present an exon-capture system for an entire class of marine invertebrates, the Ophiuroidea, built upon a phylogenetically diverse transcriptome foundation. The system captures approximately 90% of the 1,552 exon target, across all major lineages of the quarter-billion-year-old extant crown group. Key features of our system are 1) basing the target on an alignment of orthologous genes determined from 52 transcriptomes spanning the phylogenetic diversity and trimmed to remove anything difficult to capture, map, or align; 2) use of multiple artificial representatives based on ancestral state reconstructions rather than exemplars to improve capture and mapping of the target; 3) mapping reads to a multi-reference alignment; and 4) using patterns of site polymorphism to distinguish among paralogy, polyploidy, allelic differences, and sample contamination. The resulting data give a well-resolved tree (currently standing at 417 samples, 275,352 sites, 91% data-complete) that will transform our understanding of ophiuroid evolution and biogeography.
authors.affiliation: Museum Victoria, Melbourne, Vic., Australia ahugall@museum.vic.gov.au tohara@museum.vic.gov.au.
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Hugall
authors.affiliation: Museum Victoria, Melbourne, Vic., Australia ahugall@museum.vic.gov.au tohara@museum.vic.gov.au.
authors.forename: Timothy D
authors.initials: TD
authors.lastname: O'Hara
authors.affiliation: Museum Victoria, Melbourne, Vic., Australia.
authors.forename: Sumitha
authors.initials: S
authors.lastname: Hunjan
authors.affiliation: Georgia Genomics Facility, University of Georgia.
authors.forename: Roger
authors.initials: R
authors.lastname: Nilsen
authors.affiliation: Museum Victoria, Melbourne, Vic., Australia.
authors.forename: Adnan
authors.initials: A
authors.lastname: Moussalli
mesh_terms: D000818:Animals; D004272:DNA, Mitochondrial / Q000235:genetics; D004447:Echinodermata / Q000145:classification* / Q000235:genetics*; D005091:Exons / Q000235:genetics*; D023281:Genomics / Q000379:methods*; D010802:Phylogeny
chemical_list: D004272:DNA, Mitochondrial
keywords: Echinodermata; hybrid enrichment; phylogenomics