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31.
Marta Puente Molins José M. Corral Olawale Mashood Aliyu Marcus A. Koch Anja Betzin John L. Maron Timothy F. Sharbel 《Annals of botany》2014,113(3):417-427
Background and Aims
St. John''s wort (Hypericum perforatum) is becoming an important model plant system for investigations into ecology, reproductive biology and pharmacology. This study investigates biogeographic variation for population genetic structure and reproduction in its ancestral (European) and introduced (North America) ranges.Methods
Over 2000 individuals from 43 localities were analysed for ploidy, microsatellite variation (19 loci) and reproduction (flow cytometric seed screen). Most individuals were tetraploid (93 %), while lower frequencies of hexaploid (6 %), diploid (<1 %) and triploid (<1 %) individuals were also identified.Key Results
A flow cytometric analysis of 24 single seeds per individual, and five individuals per population demonstrated opposite patterns between ploidy types, with tetraploids producing more apomictic (73 %) than sexual (24 %) seed, while hexaploids produced more sexual (73 %) than apomictic (23 %) seed. As hexaploids are derived from tetraploids, these data imply that gene dosage, in addition to the effects of hybridization, influences the switch from apomictic to sexual reproduction. No significant differences in seed production were found between Europe and North America. An analysis of population structure based upon microsatellite profiling demonstrated three major genetic clusters in Europe, whose distribution was reflective of Pleistocene glaciation (e.g. refugia) and post-glacial recolonization of Europe.Conclusions
The presence of pure and mixed populations representing all three genetic clusters in North America demonstrates that H. perforatum was introduced multiple times onto the continent, followed by gene flow between the different gene pools. Taken together, the data presented here suggest that plasticity in reproduction has no influence on the invasive potential of H. perforatum. 相似文献32.
Miquel Barceló-Oliver Ángel Terrón Elies Molins Virtudes Moreno Victoria Lladó Antonio Gutiérrez 《Inorganica chimica acta》2009,362(13):4744-4753
Several new Cu-hippurate derivative-phenanthroline ternary complexes have been prepared. The X-ray structure of one of them, [Cu(hip)(phen)2]+·(hip−) (2) (where hip is hippurate and phen is 1,10-phenanthroline) has been solved. The structure of this new compound shows important differences (3D-pattern) to other similar related complexes (2D-pattern). A study of the biological activity of [Cu(hip)(phen)2]+·(hip−)·2H2O (2), [Cu(BGG)(phen)2]+·(BGG−)·6H2O (3), [Cu(BIGG)2(phen)](H2O) (4) and [Cu(I-hip)(bpy)2]+·(I-hip−)·3.5H2O (5) (where I-hip is ortho-iodohippurate, BGG corresponds to benzoylglycilglycine, and BIGG is ortho-iodobenzoylglycilglycine) is included and compared with the anti-proliferative activity of [Cu(I-hip)(phen)2]+·(I-hip−)·7H2O (1) previously described, resulting in a greater cytotoxic activity of the compounds with 1,10-phenanthroline instead of those with 2,2′-bipyridyl, in the same way that removing iodine substitution or lengthening the peptidic chain diminishes the activity of compounds compared with 1. The presence of an ortho-iodine group and the direct bond between Ar-CO and glycine moieties yield to the best results. 相似文献
33.
María Carmen Cénit Ana Márquez Miguel Cordero-Coma Marina Bego?a Gorro?o-Echebarría Alejandro Fonollosa Alfredo Adán Agustín Martínez-Berriotxoa David Díaz Valle Esperanza Pato Ricardo Blanco Joaquín Ca?al Manuel Díaz-Llopis José Luis García Serrano Enrique de Ramón María José del Rio José Manuel Martín-Villa Blanca Molins Norberto Ortego-Centeno Javier Martín 《PloS one》2013,8(11)
Objective
STAT4 and IL23R loci represent common susceptibility genetic factors in autoimmunity. We decided to investigate for the first time the possible role of different STAT4/IL23R autoimmune disease-associated polymorphisms on the susceptibility to develop non-anterior uveitis and its main clinical phenotypes.Methods
Four functional polymorphisms (rs3821236, rs7574865, rs7574070, and rs897200) located within STAT4 gene as well as three independent polymorphisms (rs7517847, rs11209026, and rs1495965) located within IL23R were genotyped using TaqMan® allelic discrimination in a total of 206 patients with non-anterior uveitis and 1553 healthy controls from Spain.Results
No statistically significant differences were found when allele and genotype distributions were compared between non-anterior uveitis patients and controls for any STAT4 (rs3821236: P=0.39, OR=1.12, CI 95%=0.87-1.43; rs7574865: P=0.59 OR=1.07, CI 95%=0.84-1.37; rs7574070: P=0.26, OR=0.89, CI 95%=0.72-1.10; rs897200: P=0.22, OR=0.88, CI 95%=0.71-1.08;) or IL23R polymorphisms (rs7517847: P=0.49, OR=1.08, CI 95%=0.87-1.33; rs11209026: P=0.26, OR=0.78, CI 95%=0.51-1.21; rs1495965: P=0.51, OR=0.93, CI 95%=0.76-1.15).Conclusion
Our results do not support a relevant role, similar to that described for other autoimmune diseases, of IL23R and STAT4 polymorphisms in the non-anterior uveitis genetic predisposition. Further studies are needed to discard a possible weak effect of the studied variant. 相似文献34.
Philippa CR Strong Stewart J Hinchliffe Hannah Patrick Steve Atkinson Olivia L Champion Brendan W Wren 《BMC microbiology》2011,11(1):85
Background
In order to identify new virulence determinants in Y. pseudotuberculosis a comparison between its genome and that of Yersinia pestis was undertaken. This reveals dozens of pseudogenes in Y. pestis, which are still putatively functional in Y. pseudotuberculosis and may be important in the enteric lifestyle. One such gene, YPTB1572 in the Y. pseudotuberculosis IP32953 genome sequence, encodes a protein with similarity to invasin, a classic adhesion/invasion protein, and to intimin, the attaching and effacing protein from enteropathogenic (EPEC) and enterohaemorraghic (EHEC) Escherichia coli. 相似文献35.
Kevin CR Kerr Sharon M Birks Mikhail V Kalyakin Yaroslav A Red'kin Eugeny A Koblik Paul DN Hebert 《Frontiers in zoology》2009,6(1):1-13
Background
Many fish species experience long periods of fasting in nature often associated with seasonal reductions in water temperature and prey availability or spawning migrations. During periods of nutrient restriction, changes in metabolism occur to provide cellular energy via catabolic processes. Muscle is particularly affected by prolonged fasting as myofibrillar proteins act as a major energy source. To investigate the mechanisms of metabolic reorganisation with fasting and refeeding in a saltwater stage of Atlantic salmon (Salmo salar L.) we analysed the expression of genes involved in myogenesis, growth signalling, lipid biosynthesis and myofibrillar protein degradation and synthesis pathways using qPCR.Results
Hierarchical clustering of gene expression data revealed three clusters. The first cluster comprised genes involved in lipid metabolism and triacylglycerol synthesis (ALDOB, DGAT1 and LPL) which had peak expression 3-14d after refeeding. The second cluster comprised ADIPOQ, MLC2, IGF-I and TALDO1, with peak expression 14-32d after refeeding. Cluster III contained genes strongly down regulated as an initial response to feeding and included the ubiquitin ligases MuRF1 and MAFbx, myogenic regulatory factors and some metabolic genes.Conclusion
Early responses to refeeding in fasted salmon included the synthesis of triacylglycerols and activation of the adipogenic differentiation program. Inhibition of MuRF1 and MAFbx respectively may result in decreased degradation and concomitant increased production of myofibrillar proteins. Both of these processes preceded any increase in expression of myogenic regulatory factors and IGF-I. These responses could be a necessary strategy for an animal adapted to long periods of food deprivation whereby energy reserves are replenished prior to the resumption of myogenesis. 相似文献36.
Sequences from the ribosomal nuclear internal transcribed spacers (ITS) have been widely used to infer evolutionary hypotheses
across a broad range of living organisms. Intraspecific sequence variation is assumed to be absent or negliable in most species,
but few detailed studies have been conducted to assess the apportionment of ITS sequence variation within and between plant
populations. Buxus balearica was chosen as a model species to assess the levels of infraspecific and intragenomic ITS variation in rare and endangered
species occurring in disjunct populations around the Mediterranean basin. Intragenomic polymorphic sites were detected for
western and eastern accessions of B. balearica and in two accessions of the sister species B. sempervirens. Overall, 19 different ribotypes were found in B. balearica after sequencing 48 clones, whereas 15 ribotypes were detected in 19 clones of B. sempervirens. The integrity and secondary structure stability of the ribosomal sequences suggest that they are not pseudogenes. The high
number of ribotypes recovered through cloning suggested that some sequences could be chimeric or generated in vivo by partial
homogenization through gene conversion or unequal crossing-over. Average sequence divergence among B. balearica clones was 0.768%, and the most divergent sequences differed by 1.62%. Available evidence does not suggest that B. balearica paralogues have been obtained from other extant Buxus species through interspecific hybridization. The presence of several ribosomal sequences in box implies that the molecular forces
driving the concerted evolution of this multigene family are not fully operational in this genus. Phylogenetic analyses of
cloned ITS sequences from B. balearica displayed very poor resolution and only two clades received moderate bootstrap support. Despite the marked intragenomic sequence
divergence found, ribosomal data suggest a clear phylogeographic split in B. balearica between western and eastern accessions. The distinct, nonchimeric sequences that are postulated as being present in each
biogeographic group suggest that box populations from Anatolia (eastern Mediterranean) are relict.
[Reviewing Editor: Dr. Rafael Zardoya] 相似文献
37.
Barceló-Oliver M Terrón A García-Raso A Fiol JJ Molins E Miravitlles C 《Journal of inorganic biochemistry》2004,98(11):1703-1711
Four ternary metal--ortho-iodohippurate (I-hip)--acyclovir (ACV) complexes, [M(I-hip)(2)(ACV)(H(2)O)(3)] where M is Co(II) (1), Ni(II) (2), Cu (3) and Zn(II) have been obtained by reaction between the corresponding binary complexes M(II)(I-hip)(2)xnH(2)O and ACV. Three ternary complexes (M=Co, Ni and Zn) and the corresponding Zn(II)--ortho-iodohippurate binary derivative have been structurally characterized by X-ray diffraction: The studies show these three ternary complexes are isostructural and present, in solid state, an interesting stacking between the nucleobase and the aryl ring of the hippurate moiety, which probably promotes the formation of ternary complexes. Moreover, the two different ligands interact between them by means of ancillary hydrogen bonds with water molecules coordinated to the metal ion. It must be mentioned that these two recognition factors, hydrogen bonds plus stacking, could explain the reason for the isostructurality of these ternary derivatives with so different three metal ions, with diverses trends in coordination numbers and geometries. In solid state, there are two enantiomeric molecules that are related by an inversion center as the crystal-building unit (as a translational motif) for the ternary complexes. 相似文献
38.
Terrón A García-Raso A Fiol JJ Amengual S Barceló-Oliver M Tótaro RM Apella MC Molins E Mata I 《Journal of inorganic biochemistry》2004,98(4):632-638
Four new complexes of uracilato and 5-halouracilato with the divalent metal ions Cu(II), Zn(II) and Ni(II) were obtained and structurally characterized. [Cu(uracilato- N(1))(2)(NH(3))(2)].2(H(2)O) (1) and [Cu(5-chlorouracilato-N(1))(2)(NH(3))(2)](H(2)O)(2) (2) complexes present distorted square planar co-ordination geometry around the metal ion. Although an additional axial water molecule is present [Cu(II)-OH(2)=2.89 A (for 1) and 2.52 A (for 2)] in both cases, only in the complex 2 would be considered in the limit of a bond distance. The Zn(II) in [Zn(5-chlorouracilato-N(1))(NH(3))(3)].(5-chlorouracilato-N(1)).(H(2)O) presents a tetrahedral co-ordination with three ammonia molecules and the N(1) of the corresponding uracilato moiety. A non-coordinated uracilato molecule is present as a counterion and a recognition between co-ordinated and free ligands, by means a tandem of H-bonds, should be mentioned. Finally, the complex [Ni(5-chlorouracilato-N(1))(2)(en)(2)] (H(2)O)(2) (where en is ethylenediamine) presents a typical octahedral trans co-ordination with additional hydrogen bonds between 5-chlorouracilato and the NH(2) groups of ethylenediamine units. 相似文献
39.
40.
Mayol M Palau C Rosselló JA González-Martínez SC Molins A Riba M 《Annals of botany》2012,109(2):429-441