Comparative Cytogenetics最新文献

{"title":"Description of the complete rDNA repeat unit structure of <i>Coturnixjaponica</i> Temminck et Schlegel, 1849 (Aves).","authors":"Alina Zhukova, Gennadii Zakharov, Olga Pavlova, Alsu Saifitdinova","doi":"10.3897/compcytogen.18.127373","DOIUrl":"10.3897/compcytogen.18.127373","url":null,"abstract":"<p><p>Ribosomal RNA (18S, 5.8S, 28S) gene clusters in genomes form regions that consist of multiple tandem repeats. They are located on a single or several pairs of chromosomes and play an important role in the formation of the nucleolus responsible for the assembly of ribosome subunits. The rRNA gene cluster sequences are widely used for taxonomic studies, however at present, complete information on the avian rDNA repeat unit structure including intergenic spacer sequence is available only for the chicken (<i>Gallusgallusdomesticus</i> Linnaeus, 1758). The GC enrichment and high-order repeats peculiarities within the intergenic spacer described for the chicken rDNA cluster may be responsible for these failures. The karyotype of the Japanese quail (<i>Coturnixjaponica</i> Temminck et Schlegel, 1849) deserves close attention because, unlike most birds, it has three pairs of nucleolar organizer bearing chromosomes, two of which are microchromosomes enriched in repeating elements and heterochromatin that carry translocated terminal nucleolar organizers. Here we assembled and annotated the complete Japanese quail ribosomal gene cluster sequence of 21166 base pairs (GenBank under the registration tag BankIt2509210 CoturnixOK523374). This is the second deciphered avian rDNA cluster after the chicken. Despite the revealed high similarity with the chicken corresponding sequence, it has a number of specific features, which include a slightly lower degree of GC content and the presence of bendable elements in the content of both the transcribed spacer I and the non-transcribed intergenic spacer.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"18 ","pages":"183-198"},"PeriodicalIF":1.0,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11447458/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142373466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Different observers introduce not negligible biases in comparative karyomorphological studies.","authors":"Lorenzo Peruzzi, Jacopo Franzoni, Manuel Tiburtini, Emanuela Abidi, Emiliano Alù, Giulio Barone, Elisabetta Bianchi, Chiara Cataudella, Emanuela Di Iorio, Maria Guerrina, Fabio Mondello, Luca Paino, Mario Pentassuglia, Manuela Porrovecchio, Giovanni Rivieccio, Eugenia Siccardi, Adriano Stinca, Alessio Tei, Virginia Volanti, Antonio Giacò","doi":"10.3897/compcytogen.18.135172","DOIUrl":"10.3897/compcytogen.18.135172","url":null,"abstract":"<p><p>Within a practical course of cytotaxonomy organized in Pisa (Italy) on February 2024 by the Group for Floristics, Systematics and Evolution of the Italian Botanical Society, we tested whether using image analysis softwares possible biases are still introduced by different observers. We conclude that observer bias selectively applies in possibly overestimating the length of short arms in a karyotype. As a consequence, the parameters most sensitive to these possible errors are CV_CI and CV_CL, and to a less degree M_CA and THL. To achieve more stable results among observers, a still lacking standardized measurement protocol could be helpful.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"18 ","pages":"175-182"},"PeriodicalIF":1.0,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11445605/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142367308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Karyotypic description and comparison of Litoria (L.) paraewingi (Watson et al., 1971), <i>L.ewingii</i> (Duméril et Bibron, 1841) and <i>L.jervisiensis</i> (Duméril et Bibron, 1841) (Amphibia, Anura).","authors":"Richard Mollard, Michael Mahony, Matt West","doi":"10.3897/compcytogen.18.129133","DOIUrl":"10.3897/compcytogen.18.129133","url":null,"abstract":"<p><p>The karyotype of Litoria (L.) paraewingi (Watson et al., 1971) (Big River State Forest, Victoria) is described here for the first time. It is prepared following tissue culture of toe clipping macerates, cryopreservation, reculture and conventional 4',6-diamidino-2-phenylindole (DAPI) staining. The <i>L.paraewingi</i> karyotype is then compared to similarly processed IUCN (International Union for the Conservation of Nature) least concern members <i>L.ewingii</i> (Duméril et Bibron, 1841) (southern Victoria) and <i>L.jervisiensis</i> (Duméril et Bibron, 1841) (Myall Lakes National Park, New South Wales), all members of the same <i>L.ewingii</i> complex/group. The <i>L.paraewingi</i> diploid number is 2n = 26, the same as for the other two species. <i>Litoriaparaewingi</i> chromosomes 1, 2, 6 and 7 are submetacentric, chromosomes 3 and 5 are subtelocentric and the remainder are metacentric. No secondary constriction or putative nucleolus organiser region (NOR) was readily identifiable following conventional DAPI staining in any scored <i>L.paraewingi</i> metaphase spread. Conversely, a putative NOR was readily identifiable on the long arm of chromosome 1 in all examined metaphase spreads for the other two species. The karyotypes of <i>L.ewingii</i> and <i>L.jervisiensis</i> here further differ from <i>L.paraewingi</i> with chromosome 1 being metacentric and chromosomes 8 and 10 being submetacentric for both former species. The <i>L.jervisiensis</i> karyotype differs from those of <i>L.ewingii</i> and <i>L.paraewingi</i> by DAPI staining with: (i) apparent relative length inversion of subtelocentric chromosome 3 and metacentric chromosome 4 and (ii) chromosome 6 being metacentric rather than submetacentric. All three species have a highly conserved chromosome morphology with respect to chromosomes 2, 5, 7, 9, 11, 12 and 13. The greatest gross morphological difference karyotypically is observed between <i>L.paraewingi</i> and <i>L.jervisiensis</i>. These karyotype data support the previous phylogenetic separation of these three species based upon genetic compatibility and behavioural, biochemical and molecular genetic analyses.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"18 ","pages":"161-174"},"PeriodicalIF":1.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11350279/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142114423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The complete chloroplast genome of <i>Rhododendronambiguum</i> and comparative genomics of related species.","authors":"Wen Bao Ma, Yafei Ou, Buddhi Dayananda, Hui Juan Ji, Tao Yu","doi":"10.3897/compcytogen.18.119929","DOIUrl":"10.3897/compcytogen.18.119929","url":null,"abstract":"<p><p><i>Rhododendron</i> Linnaeus, 1753, the largest genus of woody plants in the Northern Hemisphere, includes some of the most significant species in horticulture. <i>Rhododendronambiguum</i> Hemsl, 1911, a member of subsection Triflora Sleumer 1947, exemplifies typical alpine <i>Rhododendron</i> species. The analysis of the complete chloroplast genome of <i>R.ambiguum</i> offers new insights into the evolution of <i>Rhododendron</i> species and enhances the resolution of phylogenetic relationships. This genome is composed of 207,478 base pairs, including a pair of inverted repeats (IRs) of 47,249 bp each, separated by a large single-copy (LSC) region of 110,367 bp and a small single-copy (SSC) region of 2,613 bp. It contains 110 genes: 77 protein-coding genes, 29 tRNAs, four unique rRNAs (4.5S, 5S, 16S, and 23S), with 16 genes duplicated in the IRs. Comparative analyses reveal substantial diversity in the <i>Rhododendron</i> chloroplast genome structures, identifying a fourth variant pattern. Specifically, four highly divergent regions (<i>trnI-rpoB</i>, <i>ndhE-psaC</i>, <i>rpl32-ndhF</i>, <i>rrn16S-trnI</i>) were noted in the intergenic spacers. Additionally, 76 simple sequence repeats were identified. Positive selection signals were detected in four genes (<i>cemA</i>, <i>rps4</i>, <i>rpl16</i>, and <i>rpl14</i>), evidenced by high Ka/Ks ratios. Phylogenetic reconstruction based on two datasets (shared protein-coding genes and complete chloroplast genomes) suggests that <i>R.ambiguum</i> is closely related to <i>R.concinnum</i> Hemsley, 1889. However, the phylogenetic positions of subsection Triflora Pojarkova, 1952 species remain unresolved, indicating that the use of complete chloroplast genomes for phylogenetic research in <i>Rhododendron</i> requires careful consideration. Overall, our findings provide valuable genetic information that will enhance understanding of the evolution, molecular biology, and genetic improvement of <i>Rhododendron</i> spieces.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"18 ","pages":"143-159"},"PeriodicalIF":1.0,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11336383/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142019461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical chromosomal mapping of major ribosomal genes in 15 ant species with a review of hypotheses regarding evolution of the number and position of NORs in ants.","authors":"Monique Telcia Dos Santos Damasceno, Gisele Amaro Teixeira, Paulo Castro Ferreira, Rodrigo Batista Lod, Luísa Antônia Campos Barros, Hilton Jeferson Alves Cardoso de Aguiar","doi":"10.3897/compcytogen.18.125235","DOIUrl":"10.3897/compcytogen.18.125235","url":null,"abstract":"<p><p>Recently, hypotheses regarding the evolutionary patterns of ribosomal genes in ant chromosomes have been under discussion. One of these hypotheses proposes a relationship between chromosomal location and the number of rDNA sites, suggesting that terminal locations facilitate the dispersion of rDNA clusters through ectopic recombination during meiosis, while intrachromosomal locations restrict them to a single chromosome pair. Another hypothesis suggests that the multiplication of rDNA sites could be associated with an increase in the chromosome number in Hymenoptera due to chromosomal fissions. In this study, we physically mapped rDNA sites in 15 new ant species and also reviewed data on rDNA available since the revision by Teixeira et al. (2021a). Our objectives were to investigate whether the new data confirm the relationship between chromosomal location and the number of rDNA sites, and whether the increase in the chromosome number is significant in the dispersion of rDNA clusters in ant karyotypes. Combining our new data with all information on ant cytogenetics published after 2021, 40 new species and nine new genera were assembled. Most species exhibited intrachromosomal rDNA sites on a single chromosome pair, while three species showed these genes in terminal regions of multiple chromosome pairs. On one hand, the hypothesis that the chromosomal location of rDNA clusters may facilitate the dispersion of rDNA sites in the ant genome, as previously discussed, was strengthened, but, on the other hand, the hypothesis of chromosomal fission as the main mechanism for dispersion of ribosomal genes in ants is likely to be refuted. Furthermore, in certain genera, the location of rDNA sites remained similar among the species studied, whereas in others, the distribution of these genes showed significant variation between species, suggesting a more dynamic chromosomal evolution.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"18 ","pages":"105-122"},"PeriodicalIF":1.0,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11222723/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141535810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Karyotype analysis of <i>Quasipaaspinosa</i> David, 1875 (Anura, Dicroglossidae) with conventional cytogenetic techniques.","authors":"Liaoruilin Zhang, Jianguo Xiang, Juan Li, Jie Zhou, Jinliang Hou, Yanfei Huang, Hong Li","doi":"10.3897/compcytogen.18.116806","DOIUrl":"10.3897/compcytogen.18.116806","url":null,"abstract":"<p><p>The current study analyzed the chromosomal karyotype of <i>Quasipaaspinosa</i> David, 1875 from Hunan Province, China. The karyotype, C-banding, BrdU-banding pattern were characterized using direct preparation of bone-marrow cells and hemocyte cultures. The findings indicated that <i>Q.spinosa</i> was a diploid species (2n = 26) that lacked heteromorphic chromosomes and secondary constrictions. C-banding analysis revealed an abundance of positive signals in the centromere regions, while the BrdU-banding pattern showed three phases in both male and female, occurring consistently and in chronological sequence during S-phase. Notably, there was no asynchronous replication in the late phase. This study enhanced our understanding of the karyotypic structure of <i>Q.spinosa</i> by conventional cytogenetic techniques, thus providing essential scientific insights into the cytogenetics of <i>Q.spinosa</i>.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"18 ","pages":"97-103"},"PeriodicalIF":1.0,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11214007/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141472256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interphase nuclei, karyotypes and nuclear DNA amounts in five species of <i>Oenocarpus</i> (Arecaceae).","authors":"Natália Padilha de Oliveira, Gabriel de Siqueira Gesteira, Maria do Socorro Padilha de Oliveira, Lisete Chamma Davide","doi":"10.3897/compcytogen.18.117597","DOIUrl":"https://doi.org/10.3897/compcytogen.18.117597","url":null,"abstract":"<p><p>The genus <i>Oenocarpus</i> Martius, 1823 (Arecaceae) includes five species commonly used in Amazonia, especially for their fruits. Little is known about the cytogenetic characteristics and DNA amounts of these species, except for <i>O.bataua</i> (Martius, 1823). This study characterized and compared the types of interphase nuclei, the chromosome sets, and estimated the nuclear DNA amounts of <i>Oenocarpusbacaba</i> (Martius, 1823), <i>O.bataua</i>, <i>O.distichus</i> (Martius, 1823), <i>O.mapora</i> (H. Karsten, 1857) and <i>O.minor</i> (Martius, 1823). Standard cytogenetic analyses and estimates of the nuclear DNA amount by flow cytometry were carried out. These are the first reports of chromosome numbers and DNA amounts, except for <i>O.bataua</i>, as is the description of the chromatin distribution in interphase nuclei and karyotype for all species. All species presented 2n = 36, confirming the previous report for <i>O.bataua</i>. Differences between karyotype formulas and the positioning of secondary constrictions were observed. There were no significant differences for the nuclear DNA amounts among species. The constancy in chromosome number and variations in karyotype formulas suggest the occurrence of chromosome rearrangement as an important mechanism in <i>Oenocarpus</i> speciation.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"18 ","pages":"59-72"},"PeriodicalIF":1.0,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11096725/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140961463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of quadrivalent characteristics influencing chromosome segregation by analyzing human preimplantation embryos from reciprocal translocation carriers","authors":"Ziravard N. Tonyan, Irina L. Puppo, Alsu F. Saifitdinova, Tatyana V. Vavilova, Andrey S. Glotov","doi":"10.3897/compcytogen.18.115070","DOIUrl":"https://doi.org/10.3897/compcytogen.18.115070","url":null,"abstract":"\u0000Patterns of meiotic chromosome segregation were analyzed in cleavage stage and blastocyst stage human embryos from couples with autosomal reciprocal translocations (ART). The influence of quadrivalent asymmetry degree, the presence of terminal breakpoints, and the involvement of acrocentric chromosomes in the rearrangement were analyzed to evaluate their contribution to the formation of non-viable embryos with significant chromosomal imbalance due to pathological segregation patterns and to assess the selection of human embryos by the blastocyst stage. A selection of viable embryos resulting from alternate and adjacent-1 segregation and a significant reduction in the detection frequency of the 3 : 1 segregation pattern were observed in human embryos at the blastocyst stage. The presence of terminal breakpoints increased the frequency of 3 : 1 segregation and was also associated with better survival of human embryos resulting from adjacent-1 mode, reflecting the process of natural selection of viable embryos to the blastocyst stage. The demonstrated patterns of chromosome segregation and inheritance of a balanced karyotype in humans will contribute to optimizing the prediction of the outcomes of in vitro fertilization programs and assessing the risks of the formation of unbalanced embryos for ART carriers.","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"177 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139553262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An updated Atlas of Helophorus chromosomes","authors":"Robert B. Angus","doi":"10.3897/compcytogen.17.112831","DOIUrl":"https://doi.org/10.3897/compcytogen.17.112831","url":null,"abstract":"\u0000An account is given of my development of techniques to obtain well-spread Giemsa-stained banded chromosome preparations. Apparent G-banding could be obtained following very slight trypsin treatment of freshly prepared slides, but this banding was very fine (close-grained) and possibly not a reflection of chromosome structure. However, treatment of developing embryos in vitro with 5-fluorouridine produced a similar chromomere banding, which is therefore regarded as genuine. Steady accumulation of Helophorus Fabricius, 1775 karyotypes has resulted in the production of an Atlas covering 62 of the 170 species known to occur in the Palaearctic. Chromosome polymorphisms involving pericentric inversions and addition of extra C-banding regions have been found, as well as small B-chromosomes in a few species. In general, karyotypes have proved very useful in establishing the limits of individual species. Parthenogenesis involving triploidy has been found in two species. Karyotypes of experimentally produced hybrids have revealed irregularities in chromosome condensation.","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"34 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138825366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chromosomes of the genus Arge Schrank, 1802 (Hymenoptera, Argidae): new data and review","authors":"Vladimir E. Gokhman","doi":"10.3897/compcytogen.17.115485","DOIUrl":"https://doi.org/10.3897/compcytogen.17.115485","url":null,"abstract":"\u0000Results of the chromosome study of 12 sawfly species of the genus Arge Schrank, 1802 are reviewed, including new data on the karyotypes of A. ciliaris (Linnaeus, 1767) and A. enodis (Linnaeus, 1767) with n = 10. Moreover, the same chromosome number, n = 10, is found in A. ustulata (Linnaeus, 1758), for which n = 8 was previously reported. In addition, n = 8 is confirmed in A. gracilicornis (Klug, 1814). The results of the morphometric analysis of chromosome sets of these four species are given. In the genus Arge, haploid chromosome numbers of n = 8, 10, 11 and 13 were found. Among these sawflies, n = 8 appeared to be the most frequent chromosome number, followed by n = 10. The known data of the chromosome study of these insects are summarized and discussed in the light of phylogeny and taxonomy of the genus Arge.","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"79 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138825356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}