Karyotype and chromosomal characteristics of rDNA of Cobitis strumicae Karaman, 1955 (Teleostei, Cobitidae) from Lake Volvi, Greece

Abstract

The karyotype of Greek cobitid fish Cobitisstrumicae Karaman, 1955, from Lake Volvi, Greece, a representative of one of its two major intraspecific phylogenetic lineages, was analysed by means of sequential Giemsa-staining, C-banding, silver-staining, CMA3 fluorescence banding and also by in situ hybridization (FISH) with rDNA probe. The diploid chromosome number was 2n = 50, karyotype composed of 10 pairs of metacentric to submetacentric and 15 pairs of subtelocentric to acrocentric chromosomes. The nucleolus organizer regions (NORs) as revealed by Ag- and CMA3 staining and FISH were situated in the telomeric region of the fourth submetacentric chromosome pair. The chromosomes contained very low content of C-positive heterochromatin. No heteromorphic sex chromosomes were detected. This first karyotype report for any species of lineage Bicanestrinia Băcescu, 1962 shows a simple karyotype dominated by acrocentric chromosomes and possessing single NOR-bearing chromosome pair. Cytotaxonomic implications of this finding for the taxonomy of the genus Cobitis Linnaeus, 1758 are further discussed.

Genetic and karyotype divergence between parents affect clonality and sterility in hybrids

“…Chromosomal data for each species was obtained from the literature ( Cataudella et al, 1977 ; Hnátková et al, 2018 ; Janko et al, 2005 ; Kim and Lee, 1990 ; Kim et al, 1995 ; Marta et al, 2020 ; Suzuki and Taki, 1982 ; Ueno and Ojima, 1976 ) and present work ( Figure 1—figure supplement 2 , Supplementary file 1 ). The inspection of karyotypes was done visually and we noticed the numbers of meta-/submeta- and subtelo-/acrocentrics for each species.…”

Karyological analysis of endemic loach <i>Cobitis bilseli</i> Battalgil, 1942 (Cobitidae) in Turkey

“…The chromosomes of the two Cobitis species in Greece all have pericentromeric C-bands. In contrast, there are larger and distinct C-positive blocks on the largest metacentric chromosome of C. vardarensis (Rábová et al 2001) and two pairs of metacentric chromosomes of C. strumicae (Hnátková et al 2018). As in the Greek species, no pericentromeric distinct C-bands were found in any chromosome of C. bilseli.…”

“…The NOR phenotypes of our specimens are similar to those of C. maroccana in the Iberian Peninsula and C. strumicae in Greece. The active NOR of C. maroccana is localized to the short arm of the largest metacentric chromosome pair, as in C. biseli (Madeira et al 1992), while it was localized in the telomeric region of the short arm of the submetacentric chromosome pair in C. strumicae (Hnátková et al 2018). However, active NORs of C. vardarensis in Greece were detected on three different metacentric chromosomes (Rábová et al 2001).…”

Partial illustration of human sperm DNA via microscopy and quantitative analysis of nucleotides

“…A pattern of 5-methylCytosine Corporation has been illustrated (Fig.5f-j). Previously CMA3 brightness was used for checking the DNA quality in human sperm 24 and karyotyping 30 . The obtained images of sperm nuclear DNA stained by CMA3 (Fig.5c-d) may be pointing to a non-random localization of chromosomes 31 also is an approbation to evidence for the specific location of individual chromosomes in sperm 32, 33 .…”

“…5f-j). Previously CMA3 brightness was used for checking the DNA quality in human sperm 24 and karyotyping 30 . The obtained images of sperm nuclear DNA stained by CMA3 (Fig.…”