Phylogenomic analyses reveal latitudinal population structure and polymorphisms in heat stress genes in the North Atlantic snail Nucella lapillus

• Published in: Molecular Ecology
• Main Authors: Chu, Nathaniel D., Kaluziak, Stefan T., Trussell, Geoffrey C., Vollmer, Steven V.
• Other Authors: National Science Foundation, Brown University
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2014
• Subjects: North Atlantic; Nucella lapillus
• Online Access: http://dx.doi.org/10.1111/mec.12681; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fmec.12681; https://onlinelibrary.wiley.com/doi/pdf/10.1111/mec.12681

Abstract North A tlantic rocky intertidal species have been shaped by repeated glaciations and strong latitudinal temperature gradients, making them an excellent system to study postglacial phylogeography and thermal tolerance. Population genetics data from northwestern A tlantic species, however, often show patterns inconsistent with the prediction that high dispersal should generate weaker genetic structure among populations. Here, we used next‐generation sequencing restriction‐associated DNA tags ( RAD ‐seq) and a transcriptome assembled from RNA ‐seq data to analyse the genetic structure of northwestern A tlantic populations of the low‐dispersal intertidal snail N ucella lapillus . Although previous studies in this region have detected almost no genetic structure in N . lapillus , our phylogenomic approach identified a well‐supported split between northern and southern clades. By comparing RAD ‐seq data and our transcriptome assembly, we identified thousands of fixed single‐nucleotide polymorphisms ( SNP s) between these latitudinal clades that map to protein‐coding genes, including genes associated with heat stress tolerance. These fixed SNP s might represent loci under selection for different thermal regimes in the northwestern A tlantic.