The annotation of repetitive elements in the genome of channel catfish (Ictalurus punctatus)

PLoS One. 2018 May 15;13(5):e0197371. doi: 10.1371/journal.pone.0197371. eCollection 2018.

Abstract

Channel catfish (Ictalurus punctatus) is a highly adaptive species and has been used as a research model for comparative immunology, physiology, and toxicology among ectothermic vertebrates. It is also economically important for aquaculture. As such, its reference genome was generated and annotated with protein coding genes. However, the repetitive elements in the catfish genome are less well understood. In this study, over 417.8 Megabase (MB) of repetitive elements were identified and characterized in the channel catfish genome. Among them, the DNA/TcMar-Tc1 transposons are the most abundant type, making up ~20% of the total repetitive elements, followed by the microsatellites (14%). The prevalence of repetitive elements, especially the mobile elements, may have provided a driving force for the evolution of the catfish genome. A number of catfish-specific repetitive elements were identified including the previously reported Xba elements whose divergence rate was relatively low, slower than that in untranslated regions of genes but faster than the protein coding sequences, suggesting its evolutionary restrictions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • DNA Transposable Elements / genetics*
  • Genome / genetics*
  • Ictaluridae / genetics*
  • Microsatellite Repeats / genetics
  • Open Reading Frames / genetics
  • Repetitive Sequences, Nucleic Acid / genetics*

Substances

  • DNA Transposable Elements

Grants and funding

This project was supported by a USDA grant (grant no. 2017-67015-26295) from the Agriculture and Food Research Initiative (AFRI) under the Animal Breeding, Genetics and Genomics Program. Zihao Yuan was supported by China Scholarship Council (201406330063).