Affiliation:
1. School of Biological, Environmental, and Earth Sciences The University of Southern Mississippi Hattiesburg Mississippi USA
2. Charlotte Harbor Field Laboratory Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission Port Charlotte Florida USA
3. Florida Program for Shark Research University of Florida Gainesville Florida USA
4. Pritzker Laboratory for Molecular Systematics and Evolution, the Field Museum Chicago Illinois USA
Abstract
AbstractSawfishes (Pristidae) are large, highly threatened rays named for their tooth‐studded rostrum, which is used for prey sensing and capture. Of all five species, the smalltooth sawfish, Pristis pectinata, has experienced the greatest decline in range, currently found in only ~20% of its historic range. To better understand the genetic underpinnings of these taxonomically and morphologically unique animals, we collected transcriptomic data from several tissue types, mapped them to the recently completed reference genome, and contrasted the patterns observed with comparable data from other elasmobranchs. Evidence of positive selection was detected in 79 genes in P. pectinata, several of which are involved in growth factor/receptor tyrosine kinase signaling and body symmetry and may be related to the unique morphology of sawfishes. Changes in these genes may impact cellular responses to environmental conditions such as temperature, dissolved oxygen, and salinity. Data acquired also allow for examination of the molecular components of P. pectinata electrosensory systems, which are highly developed in sawfishes and have likely been influential in their evolutionary success.
Funder
National Oceanic and Atmospheric Administration