Abstract
Interspecific hybridization is a powerful evolutionary force. However, the investigation of hybrids requires the application of methodologies that provide efficient and indubitable identification of both parental subgenomes in hybrid individuals. Repetitive DNA, and especially the satellite DNA sequences (satDNA), can rapidly diverge even between closely related species, hence providing a useful tool for cytogenetic investigations of hybrids. Recent progress in whole-genome sequencing (WGS) offers unprecedented possibilities for the development of new tools for species determination, including identification of species-specific satDNA markers. In this study, we focused on spined loaches (Cobitis, Teleostei), a group of fishes with frequent interspecific hybridization. Using the WGS of one species, C. elongatoides, we identified seven satDNA markers, which were mapped by fluorescence in situ hybridization on mitotic and lampbrush chromosomes of C. elongatoides, C. taenia and their triploid hybrids (C. elongatoides × 2C. taenia). Two of these markers were chromosome-specific in both species, one had centromeric localization in multiple chromosomes and four had variable patterns between tested species. Our study provided a novel set of cytogenetic markers for Cobitis species and demonstrated that NGS-based development of satDNA cytogenetic markers may provide a very efficient and easy tool for the investigation of hybrid genomes, cell ploidy, and karyotype evolution.
Highlights
Interspecific hybridization is a driving force in evolution and may have various outcomes ranging from the promotion of interspecific barriers to the establishment of successful stable lineages of hybrid origin [1,2,3]
A well-studied case of hybridization-induced clonality encompasses the spined loaches of the genus Cobitis; small-sized, bottom-dwelling fishes with about 60 species that inhabit shallow freshwaters across Palearctic realm [13]
Based on the index of satellite probability provided by the TAREAN, we selected seven candidate repetitive elements with lengths ranging from 128 bp to 1820 bp for subsequent fluorescence in situ hybridization (FISH) mapping
Summary
Interspecific hybridization is a driving force in evolution and may have various outcomes ranging from the promotion of interspecific barriers to the establishment of successful stable lineages of hybrid origin [1,2,3]. A growing body of evidence suggests that hybridization can lead to the emergence of clonal (so-called “asexual”) lineages which often co-exist with one of the parental species [4,5]. Such a process has been intensively studied especially in teleost fishes, including the genera Cobitis, Carassius, Misgurnus, Squalius, and Chrosomus [6,7,8,9,10,11,12]. The Central European Cobitis hybrid complex comprises of several parental species and their hybrids.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
