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Lenka Zaveska Drabkova - One of the best experts on this subject based on the ideXlab platform.
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A Survey of Karyological Phenomena in the Juncaceae with Emphasis on Chromosome Number Variation and Evolution
The Botanical Review, 2013Co-Authors: Lenka Zaveska DrabkovaAbstract:The order Poales is well known for the presence of holocentric chromosomes, agmatoploidy, symploidy, polyploidy and high variation in chromosome numbers among and within species and genera. The second largest family of this order, Cyperaceae, is very well characterized both karyologicaly and cytologicaly. On the other hand, a smaller family Juncaceae is not so widely investigated from this point of view. The currently known chromosome numbers of the species of all eight genera of the Juncaceae are presented and variation among them is explored. Distribution of diploids, agmatoploids, agmatopolyploids, polyploids, symploids and aneuploids in the family is discussed in the phylogenetic context. Luzula is the best explored group followed by Juncus and Oreojuncus. However, only very little is known for five other Southern hemisphere genera. Fifty-eight percent of taxa from the Juncaceae are still completely unknown. Three different series of chromosome counts have been found in the Juncaceae, one for Luzula (x = 6), the second for Oreojuncus (x = 15) and the third for Juncus (x = 20) with many agmatoploid and aneuploid derivates. This outline summarizes current knowledge in chromosome count variation and karyological research in the family Juncaceae.
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DNA variation within Juncaceae: comparison of impact of organelle regions on phylogeny
Plant Systematics and Evolution, 2009Co-Authors: Lenka Zaveska Drabkova, Čestmír VlčekAbstract:A phylogenetic analysis of the Juncaceae was conducted to assess relationships among the genera Juncus, Luzula and five other small South American genera (Distichia, Marsippospermum, Oxychloe, Patosia and Rostkovia). We examined parallel datasets from organelles (mtDNA: atp1 gene, cpDNA: trnL intron, trnL-F intergenic spacer, rbcL gene) with respect to qualities relevant to the phylogenetic analysis of the Juncaceae. The main aim of our work was to produce a robust phylogeny of the Juncaceae validated by data from both organelles. Our data confirm the monophyly of the genus Luzula, but do not provide support for monophyly of the genus Juncus. The majority of taxa clustered within two subgenera, Agathryon and Juncus, morphologically supported by the presence or absence of bracteoles and cymose or racemose inflorescences, respectively. The subgenus Juncus is divided into two separate clades, the first closely related to the subgenus Agathryon and the second in the most basal part of the tree. Moreover, small South American genera clustered together with Juncus sect. Graminifolii and also with Juncus sect. Juncus. In fact, comparison of results from separate analyses of mitochondrial and plastome genes demonstrates that the general resolution of main topology of the atp1 tree is similar to the separate rbcL tree; the genus Juncus is better resolved, but the genus Luzula remains mainly polytomic.
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The phylogenetic position of Oxychloë (Juncaceae) : evidence from morphology, nuclear and plastid DNA regions
Taxon, 2007Co-Authors: Lenka Zaveska Drabkova, Čestmír VlčekAbstract:Use of molecular data for phylogenetic studies in Juncaceae/Cyperaceae beginning in 1993 has resulted in an uncertain taxonomic position of the Andean Oxychloe Phil. RbcL data used in earlier analyses resolved Oxychloe inside Cyperaceae or as their sister group. However, many typically juncaceous morphological features (e.g., spiro- or ortostichous leaves, many ovules, prominent tepals) differentiate Oxychloe from Cyperaceae. The present paper reveals relationships among the genera Oxychloe, Patosia, Distichia, Marsippospermum and Rostkovia based on both morphological and molecular data (cpDNA: rbcL, trnL intron and trnL-trnF intergenic spacer, matK and nrDNA: ITS1 & 2). Oxychloe is undoubtedly a member of Juncaceae based on both sources of data. It does not form a monophyletic lineage but is clustered with the Andean genera Patosia and Distichia. Oxychloe andina and O. bisexualis are closely related and form a sister group to O. haumaniana and O. castellanosii based on strict consensus tree of molecular data. Their position remains unresolved based on morphological data, however.
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Phylogenetic relationships within Luzula DC. and Juncus L. (Juncaceae): A comparison of phylogenetic signals of trnL-trnF intergenic spacer, trnL intron and rbcL plastome sequence data
Cladistics, 2006Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Čestmír VlčekAbstract:Juncus and Luzula are the largest, almost cosmopolitan, genera in the Juncaceae. Relationships within Juncus and Luzula and among other genera of Juncaceae (Distichia, Marsippospermum, Oxychloe, Patosia and Rostkovia) remain incompletely resolved. RbcL sequence data resolved a part of the supraspecific phylogeny, but many clades remain polytomic. For this reason, the non-coding cpDNA regions, trnL intron and trnL-trnF intergenic spacer, were sequenced. We intended to create hypotheses of relationships within Juncaceae and to test the classification of the sections, but a primary goal to this study was to assess the relationships within Juncus and Luzula and to test for monophyly of groups recognized from rbcL data (especially the monophyly of genus Luzula and the Southern Hemisphere Clade (SHC)). Furthermore, we tested the influence of different rooting and ingroup composition on the tree topology. The parsimony analyses revealed several well-supported lineages. The traditionally distinguished genus Luzula is monophyletic and Juncus is non-monophyletic. Two subgenera of Luzula (Pterodes and Luzula) are non-monophyletic, while subg. Marlenia forms a sister group to the whole Luzula clade (trnL-F data set). Within Juncus, both subgenus Juncus and subgenus Agathryon are non-monophyletic. SHC is clustered not only with the South African J. lomatophylus and J. capensis, but also together with members of the section Juncus, Caespitosi and Graminifolii. These sections form a well-separated sister group to the SHC. Within the genera Juncus and Luzula, monophyly is demonstrated for a number of groups (e.g., Juncus section Stygiopsis, Luzula section Luzula) but questioned for others (e.g., Juncus section Graminifolii). The unusual, separate positioning of Juncus trifidus and J. monanthos were clarified by trnL-trnF sequence data, but vary within the tree topology depending on outgroup selection and also due to LBA phenomenon. © The Willi Hennig Society 2006.
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DNA Taxonomy—the Riddle of Oxychloë (Juncaceae)
Systematic Botany, 2005Co-Authors: Kim A. Kristiansen, Lenka Zaveska Drabkova, Malene Cilieborg, Tina Jørgensen, Gitte Petersen, Ole SebergAbstract:Abstract Recently, advocates of DNA taxonomy have complained that there is inadequate control of the taxonomy in databases such as GenBank. This is correct, but the uncertainty may be extended to the sequences themselves. The present study shows that as long as vouchers are available neither problem is fatal, but if no voucher exists, bad sequences and bad taxonomy may be forever linked. Previous phylogenetic analyses of rbcL sequences have indicated that the small, south hemisphere, genus Oxychloe (Juncaceae) surprisingly either is embedded within or is a sister group to the Cyperaceae. This is not in accordance with traditional or current morphological data. By studying five new accessions, representing four species of Oxychloe, and re-examining the two vouchers of O. andina that were used in previous phylogenies, it has been possible to show that these two sequences are erroneous. One is a chimeric sequence and the other is most likely “a contaminant.”
Jan Kirschner - One of the best experts on this subject based on the ideXlab platform.
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SUPRASPEClFIC DIVISION OF THE GENUS JUNCOS (Juncaceae)
2016Co-Authors: Jan Kirschner, Lazaro J Novara, Vladimir S Novikov, Sven SnogerupAbstract:Abstract: A new classification fthe genus Juncus (Juncaceae) is presented. The genus is divided into wo subgenera, characterized by the presence/absence of bracteoles and the structure ofinflorescence. Lower rank subdivisions, sections, generally correspond to the tradi ionally recognized subgenera introduced by Buchenau. A new name is introduced for what has been called subg. (sect.) Ensifolii, Juncus sect. lridifolii. A checklist of supraspecific names in Juncus, with typification a d references to the sectional names accepted, is presented in the Appendix
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A New Species of Luzula Sect. Luzula (Juncaceae) from Costa Rica
Novon: A Journal for Botanical Nomenclature, 2007Co-Authors: Jan KirschnerAbstract:A new species of Luzula sect. Luzula DC., known from higher altitudes of volcanic hills in Costa Rica, is described under the name Luzula ignivoma Kirschner. It is most closely related to the Chilean species L. tristachya Desvaux. New Central American country records of other species of the Juncaceae are also given: Juncus marginatus Rostkovius from Panama, Juncus hybridus Brotero, and J. cooperi Engelmann from Mexico.
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Phylogenetic relationships within Luzula DC. and Juncus L. (Juncaceae): A comparison of phylogenetic signals of trnL-trnF intergenic spacer, trnL intron and rbcL plastome sequence data
Cladistics, 2006Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Čestmír VlčekAbstract:Juncus and Luzula are the largest, almost cosmopolitan, genera in the Juncaceae. Relationships within Juncus and Luzula and among other genera of Juncaceae (Distichia, Marsippospermum, Oxychloe, Patosia and Rostkovia) remain incompletely resolved. RbcL sequence data resolved a part of the supraspecific phylogeny, but many clades remain polytomic. For this reason, the non-coding cpDNA regions, trnL intron and trnL-trnF intergenic spacer, were sequenced. We intended to create hypotheses of relationships within Juncaceae and to test the classification of the sections, but a primary goal to this study was to assess the relationships within Juncus and Luzula and to test for monophyly of groups recognized from rbcL data (especially the monophyly of genus Luzula and the Southern Hemisphere Clade (SHC)). Furthermore, we tested the influence of different rooting and ingroup composition on the tree topology. The parsimony analyses revealed several well-supported lineages. The traditionally distinguished genus Luzula is monophyletic and Juncus is non-monophyletic. Two subgenera of Luzula (Pterodes and Luzula) are non-monophyletic, while subg. Marlenia forms a sister group to the whole Luzula clade (trnL-F data set). Within Juncus, both subgenus Juncus and subgenus Agathryon are non-monophyletic. SHC is clustered not only with the South African J. lomatophylus and J. capensis, but also together with members of the section Juncus, Caespitosi and Graminifolii. These sections form a well-separated sister group to the SHC. Within the genera Juncus and Luzula, monophyly is demonstrated for a number of groups (e.g., Juncus section Stygiopsis, Luzula section Luzula) but questioned for others (e.g., Juncus section Graminifolii). The unusual, separate positioning of Juncus trifidus and J. monanthos were clarified by trnL-trnF sequence data, but vary within the tree topology depending on outgroup selection and also due to LBA phenomenon. © The Willi Hennig Society 2006.
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trnl trnf intergenic spacer and trnl intron define major clades within luzula and juncus Juncaceae importance of structural mutations
Journal of Molecular Evolution, 2004Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Cestmir Vlcek, Vaclav PacesAbstract:Seven hundred fifty-two to one thousand ninety-seven base pairs of the trnL intron and trnL–trnF intergenic spacer of the chloroplast DNA of 55 Juncaceae taxa (Juncus, Luzula, Rostkovia, and Oxychloe) was sequenced. Seventeen structural mutations (13 indels marked A to M, 3 parts of the trnF pseudogene, and insertion “o” within a pseudogene) within the chloroplast trnL–trnF region were examined as possible indicators for phylogenetic relationships in Juncaceae. Juncus trifidus (section Steirochloa) was clearly separated from the other taxa by two large (>80 bp) indels. The “Southern Hemisphere clade” was strongly supported by a unique insertion (334 bp) in the trnL intron. The monophyly of Luzula was supported by three small (<10 bp) indels in the trnL-F spacer. They were found in all 22 examined members that represent the taxonomic and geographical diversity of the genus Luzula. A tandemly duplicated tRNA pseudogene was found in the Juncus subgenus Juncus species and is supported by four small unique indels too. The acceptor stem and D-domain-encoding regions are separated by a unique 8-bp insertion. The T-domain and acceptor stem-encoding regions were not found in the pseudogene repeats. Only the Juncus sections Ozophyllum and Iridifolii contain the 5′ acceptor stem, D-domain, and anticodon domain of the tRNAF encoding DNA. The structural mutations in the trnL intron and the trnL–trnF intergenic spacer are useful for phylogenetic reconstruction in the Juncaceae.
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TrnL–trnF Intergenic Spacer and trnL Intron Define Major Clades Within Luzula and Juncus (Juncaceae): Importance of Structural Mutations
Journal of Molecular Evolution, 2004Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Čestmír Vlček, Vaclav PacesAbstract:Seven hundred fifty-two to one thousand ninety-seven base pairs of the trn L intron and trn L– trn F intergenic spacer of the chloroplast DNA of 55 Juncaceae taxa ( Juncus , Luzula , Rostkovia , and Oxychloë ) was sequenced. Seventeen structural mutations (13 indels marked A to M, 3 parts of the trn F pseudogene, and insertion “o” within a pseudogene) within the chloroplast trn L– trn F region were examined as possible indicators for phylogenetic relationships in Juncaceae. Juncus trifidus (section Steirochloa) was clearly separated from the other taxa by two large (>80 bp) indels. The “Southern Hemisphere clade” was strongly supported by a unique insertion (334 bp) in the trn L intron. The monophyly of Luzula was supported by three small (
Čestmír Vlček - One of the best experts on this subject based on the ideXlab platform.
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DNA variation within Juncaceae: comparison of impact of organelle regions on phylogeny
Plant Systematics and Evolution, 2009Co-Authors: Lenka Záveská Drábková, Čestmír VlčekAbstract:A phylogenetic analysis of the Juncaceae was conducted to assess relationships among the genera Juncus , Luzula and five other small South American genera ( Distichia , Marsippospermum , Oxychloë , Patosia and Rostkovia ). We examined parallel datasets from organelles (mtDNA: atp 1 gene, cpDNA: trn L intron, trn L-F intergenic spacer, rbc L gene) with respect to qualities relevant to the phylogenetic analysis of the Juncaceae. The main aim of our work was to produce a robust phylogeny of the Juncaceae validated by data from both organelles. Our data confirm the monophyly of the genus Luzula , but do not provide support for monophyly of the genus Juncus. The majority of taxa clustered within two subgenera, Agathryon and Juncus , morphologically supported by the presence or absence of bracteoles and cymose or racemose inflorescences, respectively. The subgenus Juncus is divided into two separate clades, the first closely related to the subgenus Agathryon and the second in the most basal part of the tree. Moreover, small South American genera clustered together with Juncus sect. Graminifolii and also with Juncus sect. Juncus . In fact, comparison of results from separate analyses of mitochondrial and plastome genes demonstrates that the general resolution of main topology of the atp 1 tree is similar to the separate rbc L tree; the genus Juncus is better resolved, but the genus Luzula remains mainly polytomic.
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DNA variation within Juncaceae: comparison of impact of organelle regions on phylogeny
Plant Systematics and Evolution, 2009Co-Authors: Lenka Zaveska Drabkova, Čestmír VlčekAbstract:A phylogenetic analysis of the Juncaceae was conducted to assess relationships among the genera Juncus, Luzula and five other small South American genera (Distichia, Marsippospermum, Oxychloe, Patosia and Rostkovia). We examined parallel datasets from organelles (mtDNA: atp1 gene, cpDNA: trnL intron, trnL-F intergenic spacer, rbcL gene) with respect to qualities relevant to the phylogenetic analysis of the Juncaceae. The main aim of our work was to produce a robust phylogeny of the Juncaceae validated by data from both organelles. Our data confirm the monophyly of the genus Luzula, but do not provide support for monophyly of the genus Juncus. The majority of taxa clustered within two subgenera, Agathryon and Juncus, morphologically supported by the presence or absence of bracteoles and cymose or racemose inflorescences, respectively. The subgenus Juncus is divided into two separate clades, the first closely related to the subgenus Agathryon and the second in the most basal part of the tree. Moreover, small South American genera clustered together with Juncus sect. Graminifolii and also with Juncus sect. Juncus. In fact, comparison of results from separate analyses of mitochondrial and plastome genes demonstrates that the general resolution of main topology of the atp1 tree is similar to the separate rbcL tree; the genus Juncus is better resolved, but the genus Luzula remains mainly polytomic.
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The phylogenetic position of Oxychloë (Juncaceae) : evidence from morphology, nuclear and plastid DNA regions
Taxon, 2007Co-Authors: Lenka Zaveska Drabkova, Čestmír VlčekAbstract:Use of molecular data for phylogenetic studies in Juncaceae/Cyperaceae beginning in 1993 has resulted in an uncertain taxonomic position of the Andean Oxychloe Phil. RbcL data used in earlier analyses resolved Oxychloe inside Cyperaceae or as their sister group. However, many typically juncaceous morphological features (e.g., spiro- or ortostichous leaves, many ovules, prominent tepals) differentiate Oxychloe from Cyperaceae. The present paper reveals relationships among the genera Oxychloe, Patosia, Distichia, Marsippospermum and Rostkovia based on both morphological and molecular data (cpDNA: rbcL, trnL intron and trnL-trnF intergenic spacer, matK and nrDNA: ITS1 & 2). Oxychloe is undoubtedly a member of Juncaceae based on both sources of data. It does not form a monophyletic lineage but is clustered with the Andean genera Patosia and Distichia. Oxychloe andina and O. bisexualis are closely related and form a sister group to O. haumaniana and O. castellanosii based on strict consensus tree of molecular data. Their position remains unresolved based on morphological data, however.
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Phylogenetic relationships within Luzula DC. and Juncus L. (Juncaceae): A comparison of phylogenetic signals of trnL-trnF intergenic spacer, trnL intron and rbcL plastome sequence data
Cladistics, 2006Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Čestmír VlčekAbstract:Juncus and Luzula are the largest, almost cosmopolitan, genera in the Juncaceae. Relationships within Juncus and Luzula and among other genera of Juncaceae (Distichia, Marsippospermum, Oxychloe, Patosia and Rostkovia) remain incompletely resolved. RbcL sequence data resolved a part of the supraspecific phylogeny, but many clades remain polytomic. For this reason, the non-coding cpDNA regions, trnL intron and trnL-trnF intergenic spacer, were sequenced. We intended to create hypotheses of relationships within Juncaceae and to test the classification of the sections, but a primary goal to this study was to assess the relationships within Juncus and Luzula and to test for monophyly of groups recognized from rbcL data (especially the monophyly of genus Luzula and the Southern Hemisphere Clade (SHC)). Furthermore, we tested the influence of different rooting and ingroup composition on the tree topology. The parsimony analyses revealed several well-supported lineages. The traditionally distinguished genus Luzula is monophyletic and Juncus is non-monophyletic. Two subgenera of Luzula (Pterodes and Luzula) are non-monophyletic, while subg. Marlenia forms a sister group to the whole Luzula clade (trnL-F data set). Within Juncus, both subgenus Juncus and subgenus Agathryon are non-monophyletic. SHC is clustered not only with the South African J. lomatophylus and J. capensis, but also together with members of the section Juncus, Caespitosi and Graminifolii. These sections form a well-separated sister group to the SHC. Within the genera Juncus and Luzula, monophyly is demonstrated for a number of groups (e.g., Juncus section Stygiopsis, Luzula section Luzula) but questioned for others (e.g., Juncus section Graminifolii). The unusual, separate positioning of Juncus trifidus and J. monanthos were clarified by trnL-trnF sequence data, but vary within the tree topology depending on outgroup selection and also due to LBA phenomenon. © The Willi Hennig Society 2006.
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TrnL–trnF Intergenic Spacer and trnL Intron Define Major Clades Within Luzula and Juncus (Juncaceae): Importance of Structural Mutations
Journal of Molecular Evolution, 2004Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Čestmír Vlček, Vaclav PacesAbstract:Seven hundred fifty-two to one thousand ninety-seven base pairs of the trn L intron and trn L– trn F intergenic spacer of the chloroplast DNA of 55 Juncaceae taxa ( Juncus , Luzula , Rostkovia , and Oxychloë ) was sequenced. Seventeen structural mutations (13 indels marked A to M, 3 parts of the trn F pseudogene, and insertion “o” within a pseudogene) within the chloroplast trn L– trn F region were examined as possible indicators for phylogenetic relationships in Juncaceae. Juncus trifidus (section Steirochloa) was clearly separated from the other taxa by two large (>80 bp) indels. The “Southern Hemisphere clade” was strongly supported by a unique insertion (334 bp) in the trn L intron. The monophyly of Luzula was supported by three small (
Vaclav Paces - One of the best experts on this subject based on the ideXlab platform.
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trnl trnf intergenic spacer and trnl intron define major clades within luzula and juncus Juncaceae importance of structural mutations
Journal of Molecular Evolution, 2004Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Cestmir Vlcek, Vaclav PacesAbstract:Seven hundred fifty-two to one thousand ninety-seven base pairs of the trnL intron and trnL–trnF intergenic spacer of the chloroplast DNA of 55 Juncaceae taxa (Juncus, Luzula, Rostkovia, and Oxychloe) was sequenced. Seventeen structural mutations (13 indels marked A to M, 3 parts of the trnF pseudogene, and insertion “o” within a pseudogene) within the chloroplast trnL–trnF region were examined as possible indicators for phylogenetic relationships in Juncaceae. Juncus trifidus (section Steirochloa) was clearly separated from the other taxa by two large (>80 bp) indels. The “Southern Hemisphere clade” was strongly supported by a unique insertion (334 bp) in the trnL intron. The monophyly of Luzula was supported by three small (<10 bp) indels in the trnL-F spacer. They were found in all 22 examined members that represent the taxonomic and geographical diversity of the genus Luzula. A tandemly duplicated tRNA pseudogene was found in the Juncus subgenus Juncus species and is supported by four small unique indels too. The acceptor stem and D-domain-encoding regions are separated by a unique 8-bp insertion. The T-domain and acceptor stem-encoding regions were not found in the pseudogene repeats. Only the Juncus sections Ozophyllum and Iridifolii contain the 5′ acceptor stem, D-domain, and anticodon domain of the tRNAF encoding DNA. The structural mutations in the trnL intron and the trnL–trnF intergenic spacer are useful for phylogenetic reconstruction in the Juncaceae.
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TrnL–trnF Intergenic Spacer and trnL Intron Define Major Clades Within Luzula and Juncus (Juncaceae): Importance of Structural Mutations
Journal of Molecular Evolution, 2004Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Čestmír Vlček, Vaclav PacesAbstract:Seven hundred fifty-two to one thousand ninety-seven base pairs of the trn L intron and trn L– trn F intergenic spacer of the chloroplast DNA of 55 Juncaceae taxa ( Juncus , Luzula , Rostkovia , and Oxychloë ) was sequenced. Seventeen structural mutations (13 indels marked A to M, 3 parts of the trn F pseudogene, and insertion “o” within a pseudogene) within the chloroplast trn L– trn F region were examined as possible indicators for phylogenetic relationships in Juncaceae. Juncus trifidus (section Steirochloa) was clearly separated from the other taxa by two large (>80 bp) indels. The “Southern Hemisphere clade” was strongly supported by a unique insertion (334 bp) in the trn L intron. The monophyly of Luzula was supported by three small (
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TrnL–trnF Intergenic Spacer and trnL Intron Define Major Clades Within Luzula and Juncus (Juncaceae): Importance of Structural Mutations
Journal of molecular evolution, 2004Co-Authors: Lenka Zaveska Drabkova, Jan Kirschner, Čestmír Vlček, Vaclav PacesAbstract:Seven hundred fifty-two to one thousand ninety-seven base pairs of the trnL intron and trnL–trnF intergenic spacer of the chloroplast DNA of 55 Juncaceae taxa (Juncus, Luzula, Rostkovia, and Oxychloe) was sequenced. Seventeen structural mutations (13 indels marked A to M, 3 parts of the trnF pseudogene, and insertion “o” within a pseudogene) within the chloroplast trnL–trnF region were examined as possible indicators for phylogenetic relationships in Juncaceae. Juncus trifidus (section Steirochloa) was clearly separated from the other taxa by two large (>80 bp) indels. The “Southern Hemisphere clade” was strongly supported by a unique insertion (334 bp) in the trnL intron. The monophyly of Luzula was supported by three small (
A. Houben - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the small chromosomal Prionium serratum (Cyperid) demonstrates the importance of reliable methods to differentiate between mono- and holocentricity
Chromosoma, 2020Co-Authors: M. Baez, Y. T. Kuo, Y. Dias, T. Souza, A. Boudichevskaia, J. Fuchs, V. Schubert, A. L. L. Vanzela, A. Pedrosa-harand, A. HoubenAbstract:For a long time, the Cyperid clade (Thurniceae-Juncaceae-Cyperaceae) was considered a group of species possessing holocentromeres exclusively. The basal phylogenetic position of Prionium serratum (Thunb.) Drège (Thurniceae) within Cyperids makes this species an important specimen to understand the centromere evolution within this clade. In contrast to the expectation, the chromosomal distribution of the centromere-specific histone H3 (CENH3), alpha-tubulin and different centromere-associated post-translational histone modifications (H3S10ph, H3S28ph and H2AT120ph) demonstrate a monocentromeric organisation of P. serratum chromosomes. Analysis of the high-copy repeat composition resulted in the identification of two centromere-localised satellite repeats. Hence, monocentricity was the ancestral condition for the Juncaceae-Cyperaceae-Thurniaceae Cyperid clade, and holocentricity in this clade has independently arisen at least twice after differentiation of the three families, once in Juncaceae and the other one in Cyperaceae. In this context, methods suitable for the identification of holocentromeres are discussed.
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Analysis of the small chromosomal Prionium serratum (Cyperid) demonstrates the importance of a reliable method to differentiate between mono- and holocentricity
2020Co-Authors: M. Baez, Y. T. Kuo, Y. Dias, A. Boudichevskaia, J. Fuchs, V. Schubert, A. L. L. Vanzela, A. Pedrosa-harand, Thaíssa Boldieri De Souza, A. HoubenAbstract:For a long time, the Cyperid clade (Thurniceae-Juncaceae-Cyperaceae) was considered as a group of species possessing holocentromeres exclusively. The basal phylogenetic position of Prionium serratum L. f. Drege (Thurniceae) within Cyperids makes this species an important specimen to understand the centromere evolution within this clade. Unlike expected, the chromosomal distribution of the centromere-specific histone H3 (CENH3), alpha-tubulin and different centromere associated post-translational histone modifications (H3S10ph, H3S28ph and H2AT120ph) demonstrate a monocentromeric organisation of P. serratum chromosomes. Analysis of the high-copy repeat composition resulted in the identification of a centromere-localised satellite repeat. Hence, monocentricity was the ancestral condition for the Juncaceae-Cyperaceae-Thurniaceae Cyperid clade and holocentricity in this clade has independently arisen at least twice after differentiation of the three families, once in Juncaceae and the other one in Cyperaceae. Methods suitable for the identification of holocentromeres are discussed.
