Cytogenetic characterization, rDNA mapping and quantification of the nuclear DNA content in Seriolella violacea Guichenot, 1848 (Perciformes, Centrolophidae)

Abstract

Seriolella violacea Guichenot, 1848 is an important component of the fish fauna of the Chilean coast and is of great economic interest. Cytogenetic information for the family Centrolophidae is lacking and the genomic size of five of the twenty-eight species described for this family are is barely known. This study aimed to describe for the first time the karyotype structure via classical and molecular cytogenetics analysis with the goal of identifying the constitutive heterochromatin distribution, chromosome organization of rDNA sequences and quantification of nuclear DNA content. The karyotype of S. violacea is composed of 48 chromosomes, with the presence of conspicuous blocks of heterochromatin on chromosomal pairs one and two. FISH assay with a 5S rDNA probe, revealed the presence of fluorescent markings on the heterochromatic block of pair one. The 18S rDNA sites are located exclusively on pair two, characterizing this pair as the carrier of the NOR. Finally, the genomic size of S. violacea was estimated at 0.59 pg of DNA as C-value. This work represents the first effort to document the karyotype structure and physical organization of the rDNA sequences in the Seriolella genome, contributing with new information to improve our understanding of chromosomal evolution and genomic organization in marine perciforms.

Molecular Evolution and Organization of Ribosomal DNA in the Hawkweed Tribe Hieraciinae (Cichorieae, Asteraceae)

“…This indicates that while the 5S locus is always located on the same chromosome with one of the 45S rDNA loci, their sequences evolved independently. Independent evolution of both arrays was also reported in other plants and in animals (Rosato et al, 2015;Araya-Jaime et al, 2020).…”

Karyotypic analysis of Chondrostoma regium (Teleostei: Leuciscidae) distributed in the Karasu River (Erzurum)

“…According to the cytotaxonomic studies, it is seen that the karyotype of approximately 89% of these species has not been determined. From a methodological point of view, although molecular cytogenetic methods have become widespread in the world, traditional cytotaxonomic methods (Giemsa, GTG-, AgNOR-, C-, Q-and RE-banding made by air drying and culture methods) are used even in the latest studies (Araya-Jaime et al, 2020;Goes et al, 2020;Moreva, 2020). Finally, there are studies in Turkey in the field of cytogenetics that examine only some studies on carp (Saygun, 2021).…”