@article{2-s2.0-85047930327,

title = {Chromosomal distribution of rRNA genes in the karyotypes of two dioicous liverwort species from the genus Pellia Raddi},

author = { M. Orzechowska and K. Figura and D. Siwińska},

url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85047930327&doi=10.1080%2f03736687.2018.1474423&partnerID=40&md5=7c3dab07af5f051722db8eb4621a64eb},

doi = {10.1080/03736687.2018.1474423},

issn = {03736687},

year  = {2018},

date = {2018-01-01},

journal = {Journal of Bryology},

volume = {40},

number = {4},

pages = {384-392},

publisher = {Taylor and Francis Ltd.},

abstract = {Over one hundred years have passed since the first cytogenetic studies were made on the liverwort genus Pellia Raddi. The karyotype of Pellia is characterised by large chromosomes, a varying heterochromatin content and the presence of sex chromosomes in the dioicous species. Most of the Pellia species are diploids with n = 9, but one of them, Pellia borealis Lorb., has been described as an example of allopolyploidy in liverworts. Although the localisation of rRNA genes, which are essential components of the nuclear genome, remains a challenge in bryophytes, data on the number and chromosomal localisation of 35S and 5S rDNA in all of the Pellia species are now available. Previously, fluorescence in situ hybridisation using rDNA probes was performed on the mitotic chromosomes of 2 monoicous species. The aim of this study was to establish the number and chromosomal distribution of rRNA genes in 2 dioicous diploid species—Pellia endiviifolia (Dicks.) Dumort. and Pellia neesiana (Gottsche) Limpr. The relationships between the species within the genus Pellia can now be discussed in the context of the localisation of the rDNA sites and the range in the number of rDNA loci among bryophytes can also be verified. © 2018, © British Bryological Society 2018.},

note = {3},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{2-s2.0-85052958313,

title = {Organization and evolution of two repetitive sequences, 18-24J and 12-13P, in the genome of Chenopodium (Amaranthaceae)},

author = { M. Orzechowska and M. Majka and H. Weiss-Schneeweiss and A. Kovaík and N. Borowska-Zuchowska and B.A. Kolano},

url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85052958313&doi=10.1139%2fgen-2018-0044&partnerID=40&md5=4f434b61b8d0db4820323f8cfbf14c99},

doi = {10.1139/gen-2018-0044},

issn = {08312796},

year  = {2018},

date = {2018-01-01},

journal = {Genome},

volume = {61},

number = {9},

pages = {643-652},

publisher = {Canadian Science Publishing},

abstract = {The abundance and chromosomal organization of two repetitive sequences named 12-13P and 18-24J were analyzed in 24 diploid and nine polyploid species of Chenopodium s.l., with special attention to Chenopodium s.s. Both sequences were predominantly present in species of Chenopodium s.s.; however, differences in the amplification levels were observed among the species. The 12-13P repeat was highly amplified in all of the analyzed Eurasian species, whereas the American diploids showed a marked variation in the amplification levels. The 12-13P repeat contains a tandemly arranged 40 bp minisatellite element forming a large proportion of the genome of Chenopodium (up to 3.5%). FISH revealed its localization to the pericentromeric regions of the chromosomes. The chromosomal distribution of 12-13P delivered additional chromosomal marker for B-genome diploids. The 18-24J repeat showed a dispersed organization in all of the chromosomes of the analyzed diploid species and the Eurasian tetraploids. In the American allotetraploids (C. quinoa; C. berlandieri) and Eurasian allohexaploids (e.g.; C. album) very intense hybridization signals of 18-24J were observed only on 18 chromosomes that belong to the B subgenome of these polyploids. Combined cytogenetic and molecular analyses suggests that reorganization of these two repeats accompanied the diversification and speciation of diploid (especially A genome) and polyploid species of Chenopodium s.s. © 2018 Published by NRC Research Press.},

note = {6},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{2-s2.0-84969134520,

title = {Cytogenetic characterization of the Arabidopsis thaliana natural tetraploid ecotype Warschau stability during in vitro regeneration},

author = { M. Orzechowska and S. Gurdek and D. Siwińska and A. Piekarska-Stachowiak},

url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84969134520&doi=10.1007%2fs11240-016-1006-5&partnerID=40&md5=a6adece06a377085dcab6d107b964afb},

doi = {10.1007/s11240-016-1006-5},

issn = {01676857},

year  = {2016},

date = {2016-01-01},

journal = {Plant Cell, Tissue and Organ Culture},

volume = {126},

number = {3},

pages = {553-560},

publisher = {Springer Netherlands},

abstract = {The morphological and cytogenetic features of the natural autotetraploid Arabidopsis thaliana ecotype Warschau (Wa-1) were investigated. Most of the Warschau plant organs that were analyzed showed higher size values in comparison with diploid Columbia plants. The tetraploid chromosome number was confirmed by analysis of mitotic metaphase cells and rDNA loci were localized. 35S rDNA loci were present on chromosomes 2 and 4, while 5S rDNA, which is polymorphic among A. thaliana ecotypes, were present on chromosomes 4 and 5. Well-characterized autotetraploid plant material was used for in vitro culture to investigate somaclonal variation. Efficient regeneration through organogenesis was achieved. Most of the plants obtained in vitro exhibited an unchanged ploidy level. Detailed cytogenetic analysis that included chromosome, chromocenters and rDNA signals numbers, revealed the stability of regenerants. Based on these data we recommend the ecotype Warschau as a well-characterized plant material for future investigations on the consequences of polyploidy for the genome. © 2016, The Author(s).},

note = {3},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{2-s2.0-84962915550,

title = {Molecular and cytogenetic evidence for an allotetraploid origin of Chenopodium quinoa and C. berlandieri (Amaranthaceae)},

author = { B.A. Kolano and J. McCann and M. Orzechowska and D. Siwińska and E. Temsch and H. Weiss-Schneeweiss},

url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84962915550&doi=10.1016%2fj.ympev.2016.04.009&partnerID=40&md5=f32cb4019dbada940d643557f2d49c7e},

doi = {10.1016/j.ympev.2016.04.009},

issn = {10557903},

year  = {2016},

date = {2016-01-01},

journal = {Molecular Phylogenetics and Evolution},

volume = {100},

pages = {109-123},

publisher = {Academic Press Inc.},

abstract = {Most of the cultivated chenopods are polyploids, but their origin and evolutionary history are still poorly understood. Phylogenetic analyses of DNA sequences of four plastid regions, nrITS and nuclear 5S rDNA spacer region (NTS) of two tetraploid chenopods (2n = 4x = 36), Andean C. quinoa and North American C. berlandieri, and their diploid relatives allowed inferences of their origin. The phylogenetic analyses confirmed allotetraploid origin of both tetraploids involving diploids of two different genomic groups (genomes A and B) and suggested that these two might share very similar parentage.The hypotheses on the origin of the two allopolyploid species were further tested using genomic in situ hybridization (GISH). Several diploid Chenopodium species belonging to the two lineages, genome A and B, suggested by phylogenetic analyses, were tested as putative parental taxa. GISH differentiated two sets of parental chromosomes in both tetraploids and further corroborated their allotetraploid origin. Putative diploid parental taxa have been suggested by GISH for C. quinoa and C. berlandieri. Genome sizes of the analyzed allotetraploids fit nearly perfectly the expected additive values of the putative parental taxa. Directional and uniparental loss of rDNA loci of the maternal A-subgenome was revealed for both C. berlandieri and C. quinoa. © 2016 Elsevier Inc.},

note = {32},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{2-s2.0-84874224743,

title = {Chromosome variations in regenerants of Arabidopsis thaliana derived from 2- and 6-week-old callus detected using flow cytometry and FISH analyses},

author = { M. Orzechowska and K. Stępień and T. Kamińska and D. Siwińska},

url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84874224743&doi=10.1007%2fs11240-012-0232-8&partnerID=40&md5=cafa333b53cba44958311eefc1f73a57},

doi = {10.1007/s11240-012-0232-8},

issn = {01676857},

year  = {2013},

date = {2013-01-01},

journal = {Plant Cell, Tissue and Organ Culture},

volume = {112},

number = {3},

pages = {263-273},

publisher = {Kluwer Academic Publishers},

abstract = {Shoot organogenesis was induced from 2- and 6-week-old callus derived from the leaves of Arabidopsis thaliana ecotype Columbia (2n = 10). Regenerated plants were evaluated for chromosomal variations by means of flow cytometry and fluorescent in situ hybridization (FISH). Flow cytometric measurements revealed the occurrence of diploid, tetraploid, and octoploid plants among the regenerants of 2-week-old calli, whereas only diploid and tetraploid plants were regenerated from the 6-week-old calli. Chromosome counting showed that plants developed from the 2-week-old calli exhibited mixoploidy and a high frequency of aneuploid cells. These plants were infertile and displayed altered morphology. FISH with 5S and 25S rDNA probes allowed to detect some structural chromosomal rearrangements in regenerated plants. Along with cells which exhibited correct localisation of rDNA loci, also cells bearing chromosomal translocations, deletions or duplications were found. The type of structural aberrations varied between diploid and tetraploid regenerants. © 2012 The Author(s).},

note = {14},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{2-s2.0-77952941232,

title = {Molecular cytogenetic analyses of haploid and allopolyploid Pellia species},

author = { M. Orzechowska and D. Siwińska and J. Małuszyńska},

url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-77952941232&doi=10.1179%2f037366810X12578498136075&partnerID=40&md5=c38d72c6079a3105efc2ddc31c956d07},

doi = {10.1179/037366810X12578498136075},

issn = {03736687},

year  = {2010},

date = {2010-01-01},

journal = {Journal of Bryology},

volume = {32},

number = {2},

pages = {113-121},

abstract = {The allopolyploid origin of several bryophyte species was reported approximately 20 years ago. Among them the best characterized is Pellia borealis, a hybrid of two cryptic sibling species: Pellia epiphylla-species N and P. epiphylla-species S. Genomes of the allopolyploid liverwort P. borealis and its progenitors were investigated using conventional as well as molecular cytogenetic techniques. The nuclear DNA content and cell cycle phase in the thallus nuclei was established using flow cytometry. Fluorescent differential staining, C-banding and fluorescent in situ hybridization (FISH) with 26S and 5S ribosomal DNA (rDNA) probes revealed new features of the chromosomes in the P. epiphylla-P. borealis complex. Some characteristics found in both the polyploid and haploid karyotypes support earlier suggestions about the allopolyploid origin of P. borealis. The banding pattern observed on P. borealis chromosomes suggests the occurrence of structural changes in the allopolyploid genome. The number and localization of rDNA sequences were established and simultaneous FISH with 26S and 5S rDNA probes showed colocalization of both types of ribosomal RNA (rRNA) genes in Pellia chromosomes. A nuclear DNA estimate showed that the P. borealis nuclear DNA content is about twice that of the largest known nuclear genome previously known in bryophytes. © 2010 British Bryological Society.},

note = {19},

keywords = {},

pubstate = {published},

tppubtype = {article}

}