@article{BiltuevaProkopovRomanenkoetal.2020,
  author    = {Biltueva, Larisa S. and Prokopov, Dmitry Yu. and Romanenko, Svetlana A. and Interesova, Elena A. and Schartl, Manfred and Trifonov, Vladimir A.},
  title     = {Chromosome distribution of highly conserved tandemly arranged repetitive DNAs in the Siberian sturgeon (Acipenser baerii)},
  series = {Genes},
  volume    = {11},
  journal   = {Genes},
  number    = {11},
  issn      = {2073-4425},
  doi       = {10.3390/genes11111375},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219371},
  year      = {2020},
  abstract  = {Polyploid genomes present a challenge for cytogenetic and genomic studies, due to the high number of similar size chromosomes and the simultaneous presence of hardly distinguishable paralogous elements. The karyotype of the Siberian sturgeon (Acipenser baerii) contains around 250 chromosomes and is remarkable for the presence of paralogs from two rounds of whole-genome duplications (WGD). In this study, we applied the sterlet-derived acipenserid satDNA-based whole chromosome-specific probes to analyze the Siberian sturgeon karyotype. We demonstrate that the last genome duplication event in the Siberian sturgeon was accompanied by the simultaneous expansion of several repetitive DNA families. Some of the repetitive probes serve as good cytogenetic markers distinguishing paralogous chromosomes and detecting ancestral syntenic regions, which underwent fusions and fissions. The tendency of minisatellite specificity for chromosome size groups previously observed in the sterlet genome is also visible in the Siberian sturgeon. We provide an initial physical chromosome map of the Siberian sturgeon genome supported by molecular markers. The application of these data will facilitate genomic studies in other recent polyploid sturgeon species.},
  language  = {en}
}
@article{SchmidSteinlein2015,
  author    = {Schmid, Michael and Steinlein, Claus},
  title     = {Chromosome Banding in Amphibia. XXXII. The Genus Xenopus (Anura, Pipidae)},
  series = {Cytogenetic and Genome Research},
  volume    = {145},
  journal   = {Cytogenetic and Genome Research},
  number    = {3-4},
  issn      = {1424-8581},
  doi       = {10.1159/000433481},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-196727},
  pages     = {201-217},
  year      = {2015},
  abstract  = {Mitotic chromosomes of 16 species of the frog genus Xenopus were prepared from kidney and lung cell cultures. In the chromosomes of 7 species, high-resolution replication banding patterns could be induced by treating the cultures with 5-bromodeoxyuridine (BrdU) and deoxythymidine (dT) in succession, and in 6 of these species the BrdU/dT-banded chromosomes could be arranged into karyotypes. In the 3 species of the clade with 2n = 20 and 4n = 40 chromosomes (X. tropicalis, X. epitropicalis, X. new tetraploid 1), as well as in the 3 species with 4n = 36 chromosomes (X. laevis, X. borealis, X. muelleri), the BrdU/dT-banded karyotypes show a high degree of homoeology, though differences were detected between these groups. Translocations, inversions, insertions or sex-specific replication bands were not observed. Minor replication asynchronies found between chromosomes probably involve heterochromatic regions. BrdU/dT replication banding of Xenopus chromosomes provides the landmarks necessary for the exact physical mapping of genes and repetitive sequences. FISH with an X. laevis 5S rDNA probe detected multiple hybridization sites at or near the long-arm telomeric regions in most chromosomes of X. laevis and X. borealis, whereas in X. muelleri, the 5S rDNA sequences are located exclusively at the long-arm telomeres of a single chromosome pair. Staining with the AT base pair-specific fluorochrome quinacrine mustard revealed brightly fluorescing heterochromatic regions in the majority of X. borealis chromosomes which are absent in other Xenopus species.},
  language  = {en}
}