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In this study we construct a phylogenetic hypothesis for the relatedness among disjunct subspecies of Cyclamen repandum and its two allopatric congeners, C. creticum and C. balearicum in order to examine the evolutionary divergence of currently isolated populations across the western Mediterranean. The most
parsimonious phylogenetic tree obtained from sequencing the cpDNA trnL (UAA) intron suggests a major phylogeographic divide in southern Greece between two clades. The first clade comprises samples
of C. repandum subsp. peloponnesiacum (from the Peloponnese) and C. creticum (from Crete). The second comprises samples of C. repandum subsp. repandum (from Croatia, Italy, southern France, Corsica, Sardinia and Sicily), C. repandum subsp. rhodense (from Rhodes and Kos) and C. balearicum (from the Balearic Islands and southern France). These data suggest that C. creticum has evolved in allopatry from C. repandum subsp. peloponnesiacum and that C. balearicum and C. repandum ssp. rhodense have diverged from C. repandum subsp. repandum at its western and eastern distribution limits. At one small site on Corsica, a population of C. repandum may have introgressed with relictual populations of C. balearicum. These divergence patterns illustrate how a phylogenetic perspective can be used to better understand the evolution of endemism
in the Mediterranean flora.
Received February 19, 2001 Accepted August 22, 2001 相似文献
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Universal primers for amplification of three non-coding regions of chloroplast DNA 总被引:90,自引:0,他引:90
Six primers for the amplification of three non-coding regions of chloroplast DNA via the polymerase chain reaction (PCR) have been designed. In order to find out whether these primers were universal, we used them in an attempt to amplify DNA from various plant species. The primers worked for most species tested including algae, bryophytes, pteridophytes, gymnosperms and angiosperms. The fact that they amplify chloroplast DNA non-coding regions over a wide taxonomic range means that these primers may be used to study the population biology (in supplying markers) and evolution (inter- and probably intraspecific phylogenies) of plants. 相似文献
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Carla Martins Lopes Marta De Barba Frdric Boyer Cline Mercier Daniel Galiano Bruno Busnello Kubiak Renan Maestri Pedro Joel Silva da Silva Filho Ludovic Gielly Eric Coissac Thales Renato Ochotorena de Freitas Pierre Taberlet 《Molecular ecology》2020,29(16):3143-3153
Knowledge of how animal species use food resources available in the environment can increase our understanding of many ecological processes. However, obtaining this information using traditional methods is difficult for species feeding on a large variety of food items in highly diverse environments. We amplified the DNA of plants for 306 scat and 40 soil samples, and applied an environmental DNA metabarcoding approach to investigate food preferences, degree of diet specialization and diet overlap of seven herbivore rodent species of the genus Ctenomys distributed in southern and midwestern Brazil. The metabarcoding approach revealed that these species consume more than 60% of the plant families recovered in soil samples, indicating generalist feeding habits of ctenomyids. The family Poaceae was the most common food resource retrieved in scats of all species as well in soil samples. Niche overlap analysis indicated high overlap in the plant families and molecular operational taxonomic units consumed, mainly among the southern species. Interspecific differences in diet composition were influenced, among other factors, by the availability of resources in the environment. In addition, our results provide support for the hypothesis that the allopatric distributions of ctenomyids allow them to exploit the same range of resources when available, possibly because of the absence of interspecific competition. 相似文献
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Maren de Vries Adil S. Mohamed Rachel A. Prescott Ana M. Valero-Jimenez Ludovic Desvignes Rebecca OConnor Claire Steppan Joseph C. Devlin Ellie Ivanova Alberto Herrera Austin Schinlever Paige Loose Kelly Ruggles Sergei B. Koralov Annaliesa S. Anderson Joseph Binder Meike Dittmann 《Journal of virology》2021,95(10)
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France Bruck Ludovic Belle Chantal Lechanteur Laurence de Leval Muriel Hannon Sophie Dubois Emilie Castermans Stephanie Humblet-Baron Souad Rahmouni Yves Beguin Alexandra Briquet Frédéric Baron 《Cytotherapy》2013,15(3):267-279
Background aimsGraft-versus-host disease (GVHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation caused by donor T cells reacting against host tissues. Previous studies have suggested that mesenchymal stromal cells (MSCs) could exert potent immunosuppressive effects.MethodsThe ability of human bone marrow derived MSCs to prevent xenogeneic GVHD in non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice and in NOD/SCID/interleukin-2Rγ(null) (NSG) mice transplanted with human peripheral blood mononuclear cells (PBMCs) was assessed.ResultsInjection of 200 × 106 human PBMCs intraperitoneally (IP) into sub-lethally (3.0 Gy) irradiated NOD/SCID mice also given anti-asialo GM1 antibodies IP 1 day prior and 8 days after transplantation induced lethal xenogeneic GVHD in all tested mice. Co-injection of 2 × 106 MSCs IP on day 0 did not prevent lethal xenogeneic GVHD induced by injection of human PBMCs. Similarly, injection of 30 × 106 human PBMCs IP into sub-lethally (2.5 Gy) irradiated NSG mice induced a lethal xenogeneic GVHD in all tested mice. Injection of 3 × 106 MSCs IP on days 0, 7, 14 and 21 did not prevent lethal xenogeneic GVHD induced by injection of human PBMCs.ConclusionsInjection of MSCs did not prevent xenogeneic GVHD in these two humanized mice models. 相似文献