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Evolution of alcohol dehydrogenase genes in peonies (Paeonia): phylogenetic relationships of putative nonhybrid species 总被引:11,自引:0,他引:11
Alcohol dehydrogenase genes were amplified by PCR, cloned, and sequenced
from 11 putative nonhybrid species of the angiosperm genus Paeonia.
Sequences of five exons and six intron regions of the Adh gene were used to
reconstruct the phylogeny of these species. Two paralogous genes, Adh1A,
and Adh2, were found; an additional gene, Adh1B, is also present in section
Moutan. Phylogenetic analyses of exon sequences of the Adh genes of Paeonia
and a variety of other angiosperms imply that duplication of Adh1 and Adh2
occurred prior to the divergence of Paeonia species and was followed by a
duplication resulting in Adh1A and Adh1B. Concerted evolution appears to be
absent between these paralogous loci. Phylogenetic analysis of only the
Paeonia Adh exon sequences, positioning the root of the tree between the
paralogous genes Adh1 and Adh2, suggests that the first evolutionary split
within the genus occurred between the shrubby section Moutan and the other
two herbaceous sections Oneapia and Paeonia. Restriction of Adh1B genes to
section Moutan may have resulted from deletion of Adh1B from the common
ancestor of sections Oneapia and Paeonia. A relative-rate test was designed
to compare rates of molecular change among lineages based on the divergence
of paralogous genes, and the results indicate a slower rate of evolution
within the shrubby section Moutan than in section Oneapia. This may be
responsible for the relatively long branch length of section Oneapia and
the short branch length between section Moutan and the other two sections
found on the Adh, ITS (nrDNA), and matK (cpDNA) phylogenies of the genus.
Adh1 and Adh2 intron sequences cannot be aligned, and we therefore carried
out separate analyses of Adh1A and Adh2 genes using exon and intron
sequences together. The Templeton test suggested that there is not
significant incongruence among Adh1A, ITS, and matK data sets, but that
these three data sets conflict significantly with Adh2 sequence data. A
combined analysis of Adh1A, ITS, and matK sequences produced a tree that is
better resolved than that of any individual gene, and congruent with
morphology and the results of artificial hybridization. It is therefore
considered to be the current best estimate of the species phylogeny.
Paraphyly of section Paeonia in the Adh2 gene tree may be caused by longer
coalescence times and random sorting of ancestral alleles.
相似文献
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A. Laperche Y. Aigu M. Jubault M. Ollier S. Guichard P. Glory SE. Strelkov A. Gravot MJ. Manzanares-Dauleux 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(4):669-684
Key message
Nitrogen levels can modulate the effectiveness of clubroot resistance in an isolate- and host-specific manner. While the same QTL were detected under high and low nitrogen, their effects were altered.Abstract
Clubroot, caused by Plasmodiophora brassicae, is one of the most damaging diseases of oilseed rape and is known to be affected by nitrogen fertilization. However, the genetic factors involved in clubroot resistance have not been characterized under nitrogen-limiting conditions. This study aimed to assess the variability of clubroot resistance under different nitrogen levels and to characterize the impact of nitrogen supply on genetic resistance factors. Linkage analyses and a genome-wide association study were conducted to detect QTL for clubroot resistance and evaluate their sensitivity to nitrogen. The clubroot response of a set of 92 diverse oilseed rape accessions and 108 lines derived from a cross between ‘Darmor-bzh’ (resistant) and ‘Yudal’ (susceptible) was studied in the greenhouse under high- and low-nitrogen conditions, following inoculation with the P. brassicae isolates eH and K92-16. Resistance to each isolate was controlled by a major QTL and a few small-effects QTL. While the same QTL were detected under both high and low nitrogen, their effects were altered. Clubroot resistance to isolate eH, but not K92-16, was greater under a low-N supply versus a high-N supply. New sources of resistance were found among the oilseed rape accessions under both low and high-N conditions. The results are discussed relative to the literature and from a crop improvement perspective.197.
Stable isotope analysis as an early monitoring tool for community‐scale effects of rat eradication 下载免费PDF全文
Katherine M. Nigro Stacie A. Hathaway Alex S. Wegmann Ana Miller‐ter Kuile Robert N. Fisher Hillary S. Young 《Restoration Ecology》2017,25(6):1015-1025
Invasive rats have colonized most of the islands of the world, resulting in strong negative impacts on native biodiversity and on ecosystem functions. As prolific omnivores, invasive rats can cause local extirpation of a wide range of native species, with cascading consequences that can reshape communities and ecosystems. Eradication of rats on islands is now becoming a widespread approach to restore ecosystems, and many native island species show strong numerical responses to rat eradication. However, the effect of rat eradication on other consumers can extend beyond direct numerical effects, to changes in behavior, dietary composition, and other ecological parameters. These behavioral and trophic effects may have strong cascading impacts on the ecology of restored ecosystems, but they have rarely been examined. In this study, we explore how rat eradication has affected the trophic ecology of native land crab communities. Using stable isotope analysis of rats and crabs, we demonstrate that the diet or trophic position of most crabs changed subsequent to rat eradication. Combined with the numerical recovery of two carnivorous land crab species (Geograpsus spp.), this led to a dramatic widening of the crab trophic niche following rat eradication. Given the established importance of land crabs in structuring island communities, particularly plants, this suggests an unappreciated mechanism by which rat eradication may alter island ecology. This study also demonstrates the potential for stable isotope analysis as a complementary monitoring tool to traditional techniques, with the potential to provide more nuanced assessments of the community‐ and ecosystem‐wide effects of restoration. 相似文献
198.
Leonardo Restivo Bjrn Gerlach Michael Tsoory Lior Bikovski Sylvia Badurek Claudia Pitzer Isabelle C KosBraun AnneLaure MJ MaussetBonnefont Jonathan Ward Michael Schunn Lucas PJJ Noldus Anton Bespalov Vootele Voikar 《EMBO reports》2021,22(12)
Academic Core Facilities are optimally situated to improve the quality of preclinical research by implementing quality control measures and offering these to their users. Subject Categories: Methods & Resources, Science Policy & PublishingDuring the past decade, the scientific community and outside observers have noted a concerning lack of rigor and transparency in preclinical research that led to talk of a “reproducibility crisis” in the life sciences (Baker, 2016; Bespalov & Steckler, 2018; Heddleston et al, 2021). Various measures have been proposed to address the problem: from better training of scientists to more oversight to expanded publishing practices such as preregistration of studies. The recently published EQIPD (Enhancing Quality in Preclinical Data) System is, to date, the largest initiative that aims to establish a systematic approach for increasing the robustness and reliability of biomedical research (Bespalov et al, 2021). However, promoting a cultural change in research practices warrants a broad adoption of the Quality System and its underlying philosophy. It is here that academic Core Facilities (CF), research service providers at universities and research institutions, can make a difference.It is fair to assume that a significant fraction of published data originated from experiments that were designed, run, or analyzed in CFs. These academic services play an important role in the research ecosystem by offering access to cutting‐edge equipment and by developing and testing novel techniques and methods that impact research in the academic and private sectors alike (Bikovski et al, 2020). Equipment and infrastructure are not the only value: CFs employ competent personnel with profound knowledge and practical experience of the specific field of interest: animal behavior, imaging, crystallography, genomics, and so on. Thus, CFs are optimally positioned to address concerns about the quality and robustness of preclinical research. 相似文献
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Mirjam MJ Jacobs Ronald G van den Berg Vivianne GAA Vleeshouwers Marcel Visser Rolf Mank Mariëlle Sengers Roel Hoekstra Ben Vosman 《BMC evolutionary biology》2008,8(1):145
Background
The secondary genepool of our modern cultivated potato (Solanum tuberosum L.) consists of a large number of tuber-bearing wild Solanum species under Solanum section Petota. One of the major taxonomic problems in section Petota is that the series classification (as put forward by Hawkes) is problematic and the boundaries of some series are unclear. In addition, the classification has received only partial cladistic support in all molecular studies carried out to date. 相似文献200.
WS Watkins R Thara BJ Mowry Y Zhang DJ Witherspoon W Tolpinrud MJ Bamshad S Tirupati R Padmavati H Smith D Nancarrow C Filippich LB Jorde 《BMC genetics》2008,9(1):1-17