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91.
Santiago Andrés Catalano Beatriz Ofelia Saidman Juan César Vilardi 《Cladistics : the international journal of the Willi Hennig Society》2009,25(1):93-104
Small inversions (SIs) in the chloroplast genome of angiosperms are ubiquitous. These inversions are always flanked by inverted repeats (palindromes or quasipalindromes) between approximately 8 and 50 bp long that form a hairpin structure when the DNA is single-stranded. We evaluated different methodological and empirical issues about SI evolution. As a case study, we analysed an SI recently discovered in the psb C– trn S intergenic region of Prosopis (Fabaceae). First, we analysed how inversions can be optimized in cases where the inverted segment also shows indels and substitutions, proposing a method based on Fixed States Optimization. Second, we evaluated the occurrence of this inversion on a phylogeny that includes the major lineages of angiosperms. Finally, we assessed whether the occurrence of this inversion was related to the thermodynamic stability of the hairpin structure (measured by its corresponding free energy) and/or the length of the palindromes by using a modified version of Maddison's Concentrated Changes Test. Hairpin structure was conserved in most of the 154 sequences analysed, with the inversion taking place at least 10 times in different lineages (monocots, magnoliids, rosids). As was previously proposed for other SIs, our analysis strongly suggests that the occurrence of this inversion is correlated with higher hairpin stability. In contrast, we found no evidence of a correlation with longer palindromes. Our results are in agreement with the hypothesis that hairpin formation is a requisite for SI occurrence. However, alternative explanations cannot be discarded.
© The Willi Hennig Society 2008. 相似文献
© The Willi Hennig Society 2008. 相似文献
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Leandro Gabriel Roser Laura Inés Ferreyra Mauricio Ewens Juan César Vilardi Beatriz Ofelia Saidman 《Tree Genetics & Genomes》2014,10(2):383-397
Prosopis alba is an important Argentinean species with a great potential for the production of timber and nontimber products. Many studies showed high salt tolerance of this species, which allows it to be used in afforestation and reforestation of saline soils. In this study, we applied the morphometric technique to characterize 21 salt-tolerant clones (ST). Twenty of these clones were studied by inter-simple sequence repeat (ISSR) and simple sequence repeat (SSR), and their molecular patterns were compared with those of 22 individuals selected for salt sensitivity (SS). Most morphological traits revealed highly significant differences among ST clones, and four out of 11 characters showed high heritability. ISSR analysis allowed detecting 89 loci, 91 % of them variable. ST versus SS groups differ significantly from each other by the frequencies of 22 of these loci, from which 12 were significant at the matrix level. Analysis of six SSR loci for the same groups indicated that all of them were polymorphic at the 1 % criterion. Allelic frequencies of SSR also showed highly significant differences between SS and ST groups. Analysis of coancestry between individuals within SS and ST groups and between groups indicated that the molecular differentiation between them cannot be explained solely on relationship grounds. Molecular groupings based on ISSR and SSR showed consistency to each other, as supported by the highly significant coinertia in the distribution of individuals in principal component analysis scatterplots. This work is the first contribution which tends to associate molecular patterns with life history traits and morphological differences in Prosopis clones. 相似文献
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The two alkaloids, α- and β-erythroidine have been identified in 0.034 and 0.11 % yield in flowers of Erythrina americana and could be responsible for the hypnotic activity of flower extracts. 相似文献
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Pérez-Alquicira Jessica Wehncke Elisabet V. García-Loza Gustavo A. Carstens Bryan C. Domínguez César A. Pérez-Ishiwara Rubén Molina-Freaner Francisco E. Zamora-Tavares María del Pilar Rico Yessica Cabrera-Toledo Dánae Vargas-Ponce Ofelia Rodríguez Aarón Ezcurra Exequiel 《Journal of plant research》2023,136(3):277-290
Journal of Plant Research - The formation of the Baja California Peninsula (BCP) has impacted the microevolutionary dynamics of different species in ways that depend on biological traits such as... 相似文献
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Synaptic activity‐induced glycolysis facilitates membrane lipid provision and neurite outgrowth
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