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81.
82.
Fine‐scale spatial genetic structure analysis of the black truffle Tuber aestivum and its link to aroma variability 下载免费PDF全文
Virginie Molinier Claude Murat Henri Frochot Daniel Wipf Richard Splivallo 《Environmental microbiology》2015,17(8):3039-3050
Truffles are symbiotic fungi in high demand by food connoisseurs. Improving yield and product quality requires a better understanding of truffle genetics and aroma biosynthesis. One aim here was to investigate the diversity and fine‐scale spatial genetic structure of the Burgundy truffle Tuber aestivum. The second aim was to assess how genetic structuring along with fruiting body maturation and geographical origin influenced single constituents of truffle aroma. A total of 39 Burgundy truffles collected in two orchards were characterized in terms of aroma profile (SPME‐GC/MS) and genotype (microsatellites). A moderate genetic differentiation was observed between the populations of the two orchards. An important seasonal and spatial genetic structuring was detected. Within one orchard, individuals belonging to the same genet were generally collected during a single season and in the close vicinity from each other. Maximum genet size nevertheless ranged from 46 to 92 m. Geographical origin or maturity only had minor effects on aroma profiles but genetic structuring, specifically clonal identity, had a pronounced influence on the concentrations of C8‐ and C4‐VOCs. Our results highlight a high seasonal genetic turnover and indicate that the aroma of Burgundy truffle is influenced by the identity of single clones/genets. 相似文献
83.
Quraishi UM Abrouk M Murat F Pont C Foucrier S Desmaizieres G Confolent C Rivière N Charmet G Paux E Murigneux A Guerreiro L Lafarge S Le Gouis J Feuillet C Salse J 《The Plant journal : for cell and molecular biology》2011,65(5):745-756
Monitoring nitrogen use efficiency (NUE) in plants is becoming essential to maintain yield while reducing fertilizer usage. Optimized NUE application in major crops is essential for long-term sustainability of agriculture production. Here, we report the precise identification of 11 major chromosomal regions controlling NUE in wheat that co-localise with key developmental genes such as Ppd (photoperiod sensitivity), Vrn (vernalization requirement), Rht (reduced height) and can be considered as robust markers from a molecular breeding perspective. Physical mapping, sequencing, annotation and candidate gene validation of an NUE metaQTL on wheat chromosome 3B allowed us to propose that a glutamate synthase (GoGAT) gene that is conserved structurally and functionally at orthologous positions in rice, sorghum and maize genomes may contribute to NUE in wheat and other cereals. We propose an evolutionary model for the NUE locus in cereals from a common ancestral region, involving species specific shuffling events such as gene deletion, inversion, transposition and the invasion of repetitive elements. 相似文献
84.
Bailey K Cevik V Holton N Byrne-Richardson J Sohn KH Coates M Woods-Tör A Aksoy HM Hughes L Baxter L Jones JD Beynon J Holub EB Tör M 《Molecular plant-microbe interactions : MPMI》2011,24(7):827-838
RPP5 is the seminal example of a cytoplasmic NB-LRR receptor-like protein that confers downy mildew resistance in Arabidopsis thaliana. In this study, we describe the cloning and molecular characterization of the gene encoding ATR5(Emoy2), an avirulence protein from the downy mildew pathogen Hyaloperonospora arabidopsidis isolate Emoy2. ATR5(Emoy2) triggers defense response in host lines expressing the functional RPP5 allele from Landsberg erecta (Ler-0). ATR5(Emoy2) is embedded in a cluster with two additional ATR5-like (ATR5L) genes, most likely resulting from gene duplications. ATR5L proteins do not trigger RPP5-mediated resistance and the copy number of ATR5L genes varies among H. arabidopsidis isolates. ATR5(Emoy2) and ATR5L proteins contain a signal peptide, canonical EER motif, and an RGD motif. However, they lack the canonical translocation motif RXLR, which characterizes most oomycete effectors identified so far. The signal peptide and the N-terminal regions including the EER motif of ATR5(Emoy2) are not required to trigger an RPP5-dependent immune response. Bioinformatics screen of H. arabidopsidis Emoy2 genome revealed the presence of 173 open reading frames that potentially encode for secreted proteins similar to ATR5(Emoy2), in which they share some motifs such as EER but there is no canonical RXLR motif. 相似文献
85.
Morning- and evening-type individuals differ on a number of psychological and biological variables. There has been increasing interest in the relationship between chronotype and personality traits. The aim of this study was to investigate the relationship between impulsivity and chronotype in suicide attempters. Eighty-nine suicide attempters were included in the study, and systematic information on suicide attempts was recorded. The Morningness-Eveningness Questionnaire was applied to determine chronotype, and attempter impulsivity was measured by the total score of the Barratt Impulsiveness Scale. Significant differences between chronotype and impulsivity scores were found. Evening-type subjects reported significantly higher impulsivity scores than both neither- and morning-types. A significant association between chronotype and type of suicide attempt was detected. The largest proportion of violent suicide attempters were evening-type subjects. Violent suicide attempters also reported significantly higher impulsivity scores than nonviolent attempters. Previous studies have pointed out possible relations between eveningness and impulsivity. Current findings suggest that eveningness may be a risk factor for violent suicide attempts by increasing impulsivity. 相似文献
86.
Durdagi S Şentürk M Ekinci D Balaydın HT Göksu S Küfrevioğlu Öİ Innocenti A Scozzafava A Supuran CT 《Bioorganic & medicinal chemistry》2011,19(4):1381-1389
Carbonic anhydrases (CAs, EC 4.2.1.1) are inhibited by sulfonamides, inorganic anions, phenols, coumarins (acting as prodrugs) and polyamines. A novel class of CA inhibitors (CAIs), interacting with the CA isozymes I, II (cytosolic) and IX, XII (transmembrane, tumor-associated) in a different manner, is reported here. Kinetic measurements allowed us to identify hydroxy-/methoxy-substituted benzoic acids as well as di-/tri-methoxy benzenes as submicromolar-low micromolar inhibitors of the four CA isozymes. Molecular docking studies of a set of such inhibitors within CA I and II allowed us to understand the inhibition mechanism. This new class of inhibitors binds differently compared to all other classes of inhibitors known to date: they were found between the phenol-binding site and the coumarin-binding site, filling thus the middle of the enzyme cavity. They exploit different interactions with amino acid residues and water molecules from the CA active site compared to other classes of inhibitors, offering the possibility to design CAIs with an interesting inhibition profile compared to the clinically used sulfonamides/sulfamates. 相似文献
87.
Mayer KF Martis M Hedley PE Simková H Liu H Morris JA Steuernagel B Taudien S Roessner S Gundlach H Kubaláková M Suchánková P Murat F Felder M Nussbaumer T Graner A Salse J Endo T Sakai H Tanaka T Itoh T Sato K Platzer M Matsumoto T Scholz U Dolezel J Waugh R Stein N 《The Plant cell》2011,23(4):1249-1263
We used a novel approach that incorporated chromosome sorting, next-generation sequencing, array hybridization, and systematic exploitation of conserved synteny with model grasses to assign ~86% of the estimated ~32,000 barley (Hordeum vulgare) genes to individual chromosome arms. Using a series of bioinformatically constructed genome zippers that integrate gene indices of rice (Oryza sativa), sorghum (Sorghum bicolor), and Brachypodium distachyon in a conserved synteny model, we were able to assemble 21,766 barley genes in a putative linear order. We show that the barley (H) genome displays a mosaic of structural similarity to hexaploid bread wheat (Triticum aestivum) A, B, and D subgenomes and that orthologous genes in different grasses exhibit signatures of positive selection in different lineages. We present an ordered, information-rich scaffold of the barley genome that provides a valuable and robust framework for the development of novel strategies in cereal breeding. 相似文献
88.
89.
In this work, modified carboxymethylcellulose (CMC) was used as a new support material for production of ethanol. Crosslinked
graft copolymers of CMC with N-vinyl-2-pyrrolidone (N-VP) were prepared in different grafting yields. The beads material was characterized by means of fourier transform infrared
spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscope (SEM) and swelling experiment.
Saccharomyces cerevisiae was immobilized using entrapment method in the graft copolymers of carboxymethylcellulose-g-poly(N-vinyl-2-pyrrolidone) (CMC-g-PVP)
for ethanol fermentation. The effects of grafting yield, initial glucose concentration and crosslinker concentration on the
yield of ethanol process were investigated. Reusability of the immobilized yeasts was investigated and found that the materials
can be used four times without losing their activity. Ethanol production increased to 59.3 g/L from 46.4 g/L when percentage
of N-VP in the graft copolymer was increased. The highest ethanol productivity was found to be 1.75–2.25 g/L h. Fermentation time
decreased with the decreasing of crosslinker concentration. The results suggest that the proposed method for immobilization
of Saccharomyces cerevisiae has potential in industrial applications for ethanol process. 相似文献
90.
Sogut S Yonden Z Kaya H Oktar S Tutanc M Yilmaz HR Yigit A Ozcelik N Gali E 《Genetics and molecular research : GMR》2011,10(2):828-833
Oxidative stress may be contributory to the pathophysiology of the abnormalities that underlie the clinical course of sickle cell anemia. We looked for a possible genetic association between the functional polymorphism Ala-9Val in the human Mn-SOD gene and sickle cell anemia. One hundred and twenty-seven patients with sickle cell anemia and 127 healthy controls were recruited into the study. Alanine versus valine polymorphism in the signal peptide of the Mn-SOD gene was evaluated using a primer pair to amplify a 107-bp fragment followed by digestion with the restriction enzyme NgoMIV. In the sickle cell anemia patients, the frequency of Val/Val genotype was approximately 1.4-fold lower and that of Ala/Val was 1.3-fold higher compared to the controls. No significant difference in genotype frequencies was found between patients and controls (χ(2) = 4.561, d.f. = 2, P = 0.101). The Val-9 was the most common allele in patient and healthy subjects. No significant difference in allele frequencies was found between patients and controls (χ(2) = 1.496, d.f. = 1, P = 0.221). We conclude that the Mn-SOD gene polymorphism is not associated with sickle cell anemia. 相似文献