4 research outputs found

    The Chromosome Number and rDNA Loci Evolution in Onobrychis (Fabaceae)

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    The evolution of chromosome number and ribosomal DNA (rDNA) loci number and localisation were studied in Onobrychis Mill. Diploid and tetraploid species, as well as two basic chromosome numbers, x = 7 and x = 8, were observed among analysed taxa. The chromosomal distribution of rDNA loci was presented here for the first time using fluorescence in situ hybridisation (FISH) with 5S and 35S rDNA probes. Onobrychis species showed a high polymorphism in the number and localisation of rDNA loci among diploids, whereas the rDNA loci pattern was very similar in polyploids. Phylogenetic relationships among the species, inferred from nrITS sequences, were used as a framework to reconstruct the patterns of basic chromosome number and rDNA loci evolution. Analysis of the evolution of the basic chromosome numbers allowed the inference of x = 8 as the ancestral number and the descending dysploidy and polyploidisation as the major mechanisms of the chromosome number evolution. Analyses of chromosomal patterns of rRNA gene loci in a phylogenetic context resulted in the reconstruction of one locus of 5S rDNA and one locus of 35S rDNA in the interstitial chromosomal position as the ancestral state in this genus

    Karyomorphology and nuclear DNA content of sixteen Ophrys L. taxa from Turkey

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    Karyotypes in 16 representative taxa of the Ophrys genus are compared, based on Feulgen-stained somatic metaphase chromosomes. The karyotypes of O. omegaifera subsp. israelitica, O. ulupinara, O. lycia, O. argolica subsp. lucis, O. argolica subsp. lesbis, O. climacis and O. reinholdii subsp. reinholdii are described for the first time. Karyological analyses indicate relationships among the species with respect to their asymmetry indices. All Ophrys taxa studied were diploid with 2n=2x=36 chromosomes. One B chromosome has been detected among the chromosomes of O. argolica subsp. lucis. All karyotypes are symmetrical, consisting of metacentric and submetacentric chromosomes. The longest chromosomes of all the investigated specimens contain a secondary constriction. It is determined that there is a correlation between the total number of chromosomes having secondary constrictions and the evolutionary development order of the taxa. Based on nuclear DNA content, analysis was carried out by flow cytometer using propodium iodide as fluorochrome, 2C nuclear DNA content of 16 Ophrys species varying between 20.80pg (O. argolica subsp. lucis) and 23.11pg (O. omegaifera subsp. israelitica). Karyotype asymmetry relationships are discussed according to the bidimensional scatter plots of A(1)-A(2), CVCL-CVCI, CVCL-M-CA and CVCI-M-CA

    Molecular cytogenetic characterization of common bean (Phaseolus vulgaris L.) accessions

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    WOS:000599463300007With an annual global production of approximately 25 million tons, the common bean (Phaseolus vulgaris L), a member of the genus Phaseolus, is one of the major protein sources used as food for humans. in this study, it was aimed to investigate the genome size of the common bean genetic resource collection (154 common bean accessions) in Turkey by flow cytometry (FCM) and determine whether geographical variables affected the genome size. in addition, the number and distribution of 5S and 45S ribosomal DNA loci were designated by performing a fluorescence in situ hybridization (FISH) analysis in some of the accessions. The FCM analyses revealed that the mean nuclear DNA content of the accessions varied from 1.28 pg2C-1 to 1.55 pg2G1 (mean 1.35 pg2C-1), and the differences between these accessions were statistically significant (P < 0.01). Intraspecific variation in the genome size was determined, and a positive correlation was found between the altitude and genome size. However, latitude and longitude did not have any statistically significant effect on the genome size. in the principal coordinate analysis, the accessions were divided into 3groups. Based on the results of the FISH analysis performed on 5 different accessions with varying genome sizes, using 5S and 45S rDNA genes as probes, the number of 5S rDNA loci was 4 in the common bean and stable among the common bean accessions, while the number of 45S rDNA loci was highly polymorphic, varying between 6 and 16. Consequently, it was determined in the present study that the genetic resource collection of common bean had a wide variation in terms of genome size and genome organization.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [116O057]We would like to thank the Scientific and Technological Research Council of Turkey (TUBITAK) for providing financial support for this study under project no. 116O057

    The relation between distant metastasis and genetic change type in stage IV lung adenocarcinoma patients at diagnosis

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    Introduction Brain metastasis prevalence is higher in patients with positive epidermal growth factor receptor (EGFR) mutation, anaplastic lymphoma kinase (ALK) and C-ROS oncogene 1 (ROS-1) fusion change in lung adenocarcinoma. Objectives The purpose of our study is to investigate the relation between the genetic change type and the initial distant metastasis in stage IV lung adenocarcinoma patients with genetic changes. Methods The study was conducted between January 2007 and December 2018 in a retrospective fashion with patients who had lung cancer diagnosed as stage IV adenocarcinoma. The relation between genetic mutation change (EGFR, ALK or ROS-1) and distant metastasis was analysed. Results A total of 845 patients were included in the study. The median age was 62 (28-88). It was determined that lung and pleura metastases were more frequent at a significant level in patients with positive EGFR mutation (P = 0.032,P = 0.004, respectively). In patients with positive ALK fusion change, pleura metastasis was determined to be more frequent (P = 0.001). Multiple metastases were determined to be significantly more in patients with positive ALK fusion change than single metastasis (P = 0.02). Conclusion In patients with EGFR mutant lung adenocarcinoma, lung and pleura metastasis is more frequent and pleura metastasis is more frequent in ALK positive adenocarcinoma. Additionally, multiple organ metastases are higher in ALK positive lung adenocarcinoma
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