A dense single-nucleotide polymorphism-based genetic linkage map of grapevine (Vitis vinifera L.) anchoring Pinot Noir bacterial artificial chromosome contigs

The construction of a dense genetic map for Vitis vinifera and its anchoring to a BAC-based physical map is described: it includes 994 loci mapped onto 19 linkage groups, corresponding to the basic chromosome number of Vitis. Spanning 1245 cM with an average distance of 1.3 cM between adjacent markers, the map was generated from the segregation of 483 single-nucleotide polymorphism (SNP)-based genetic markers, 132 simple sequence repeats (SSRs), and 379 AFLP markers in a mapping population of 94 F(1) individuals derived from a V. vinifera cross of the cultivars Syrah and Pinot Noir. Of these markers, 623 were anchored to 367 contigs that are included in a physical map produced from the same clone of Pinot Noir and covering 352 Mbp. On the basis of contigs containing two or more genetically mapped markers, region-dependent estimations of physical and recombinational distances are presented. The markers used in this study include 118 SSRs common to an integrated map derived from five segregating populations of V. vinifera. The positions of these SSR markers in the two maps are conserved across all Vitis linkage groups. The addition of SNP-based markers introduces polymorphisms that are easy to database, are useful for evolutionary studies, and significantly increase the density of the map. The map provides the most comprehensive view of the Vitis genome reported to date and will be relevant for future studies on structural and functional genomics and genetic improvement.     

The golden beauty: brain response to classical and renaissance sculptures

Is there an objective, biological basis for the experience of beauty in art? Or is aesthetic experience entirely subjective? Using fMRI technique, we addressed this question by presenting viewers, naïve to art criticism, with images of masterpieces of Classical and Renaissance sculpture. Employing proportion as the independent variable, we produced two sets of stimuli: one composed of images of original sculptures; the other of a modified version of the same images. The stimuli were presented in three conditions: observation, aesthetic judgment, and proportion judgment. In the observation condition, the viewers were required to observe the images with the same mind-set as if they were in a museum. In the other two conditions they were required to give an aesthetic or proportion judgment on the same images. Two types of analyses were carried out: one which contrasted brain response to the canonical and the modified sculptures, and one which contrasted beautiful vs. ugly sculptures as judged by each volunteer. The most striking result was that the observation of original sculptures, relative to the modified ones, produced activation of the right insula as well as of some lateral and medial cortical areas (lateral occipital gyrus, precuneus and prefrontal areas). The activation of the insula was particularly strong during the observation condition. Most interestingly, when volunteers were required to give an overt aesthetic judgment, the images judged as beautiful selectively activated the right amygdala, relative to those judged as ugly. We conclude that, in observers naïve to art criticism, the sense of beauty is mediated by two non-mutually exclusive processes: one based on a joint activation of sets of cortical neurons, triggered by parameters intrinsic to the stimuli, and the insula (objective beauty); the other based on the activation of the amygdala, driven by one''s own emotional experiences (subjective beauty).     

Polyunsaturated fatty acid pattern in liver and erythrocyte phospholipids from obese patients

Objective: Our aim was to study the fatty acid (FA) composition of liver phospholipids and its relation to that in erythrocyte membranes from patients with obese nonalcoholic fatty liver disease (NAFLD), as an indication of lipid metabolism alterations leading to steatosis. Research Methods and Procedures: Eight control subjects who underwent antireflux surgery and 12 obese patients with NAFLD who underwent subtotal gastrectomy with a gastro‐jejunal anastomosis in Roux‐en‐Y were studied. The oxidative stress status of patients was assessed by serum F₂‐isoprostanes levels (gas chromatography/negative ion chemical ionization tandem mass spectrometry). Analysis of FA composition of liver and erythrocyte phospholipids was carried out by gas‐liquid chromatography. Results: Patients with NAFLD showed serum F₂‐isoprostanes levels 84% higher than controls. Compared with controls, liver phospholipids from obese patients exhibited significantly 1) lower levels of 20:4n‐6, 22:5n‐3, 22:6n‐3 [docosahexaenoic acid (DHA)], total long‐chain polyunsaturated FA (LCPUFA), and total n‐3 LCPUFA, 2) higher 22:5n‐6 [docosapentaenoic acid (DPAn‐6)] levels and n‐6/n‐3 LCPUFA ratios, and 3) comparable levels of n‐6 LCPUFA. Levels of DHA and DPAn‐6 in liver were positively correlated with those in erythrocytes (r = 0.77 and r = 0.90, respectively; p < 0.0001), whereas DHA and DPAn‐6 showed a negative association in both tissues (r = ?0.79, p < 0.0001 and r = ?0.58, p < 0.01, respectively), associated with lower DHA/DPAn‐6 ratios. Discussion: Obese patients with NAFLD showed marked alterations in the polyunsaturated fatty acid pattern of the liver. These changes are significantly correlated with those found in erythrocytes, thus suggesting that erythrocyte FA composition could be a reliable indicator of derangements in liver lipid metabolism in obese patients.     

Identification of amino acid residues critical for the B cell growth-promoting activity of HIV-1 matrix protein p17 variants

Background

HIV-1 matrix protein p17 variants (vp17s) detected in HIV-1-infected patients with non-Hodgkin's lymphoma (HIV-NHL) display, differently from the wild-type protein (refp17), B cell growth-promoting activity. Biophysical analysis revealed that vp17s are destabilized as compared to refp17, motivating us to explore structure-function relationships.

Tuber borchii fruit body: 2-dimensional profile and protein identification

The formation of the fruit body represents the final phase of the ectomycorrhizal fungus T. borchii life cycle. Very little is known concerning the molecular and biochemical processes involved in the fructification phase. 2-DE maps of unripe and ripe ascocarps revealed different protein expression levels and the comparison of the electropherograms led to the identification of specific proteins for each developmental phase. Associating micropreparative 2-DE to microchemical approaches, such as N-terminal sequencing and 2-D gel-electrophoresis mass-spectrometry, proteins playing pivotal roles in truffle physiology were identified.     

Targeted modification of homogalacturonan by transgenic expression of a fungal polygalacturonase alters plant growth

Pectins are a highly complex family of cell wall polysaccharides comprised of homogalacturonan (HGA), rhamnogalacturonan I and rhamnogalacturonan II. We have specifically modified HGA in both tobacco (Nicotiana tabacum) and Arabidopsis by expressing the endopolygalacturonase II of Aspergillus niger (AnPGII). Cell walls of transgenic tobacco plants showed a 25% reduction in GalUA content as compared with the wild type and a reduced content of deesterified HGA as detected by antibody labeling. Neutral sugars remained unchanged apart from a slight increase of Rha, Ara, and Gal. Both transgenic tobacco and Arabidopsis were dwarfed, indicating that unesterified HGA is a critical factor for plant cell growth. The dwarf phenotypes were associated with AnPGII activity as demonstrated by the observation that the mutant phenotype of tobacco was completely reverted by crossing the dwarfed plants with plants expressing PGIP2, a strong inhibitor of AnPGII. The mutant phenotype in Arabidopsis did not appear when transformation was performed with a gene encoding AnPGII inactivated by site directed mutagenesis.     

Structure and function of the Gondwanian hemoglobin of Pseudaphritis urvillii, a primitive notothenioid fish of temperate latitudes

The suborder Notothenioidei dominates the Antarctic ichthyofauna. The non-Antarctic monotypic family Pseudaphritidae is one of the most primitive families. The characterization of the oxygen-transport system of euryhaline Pseudaphritis urvillii is herewith reported. Similar to most Antarctic notothenioids, this temperate species has a single major hemoglobin (Hb 1, over 95% of the total). Hb 1 has strong Bohr and Root effects. It shows two very uncommon features in oxygen binding: At high pH values, the oxygen affinity is exceptionally high compared to other notothenioids, and subunit cooperativity is modulated by pH in an unusual way, namely the curve of the Hill coefficient is bell-shaped, with values approaching 1 at both extremes of pH. Molecular modeling, electronic absorption and resonance Raman spectra have been used to characterize the heme environment of Hb 1 in an attempt to explain these features, particularly in view of some potentially important nonconservative replacements found in the primary structure. Compared to human HbA, no major changes were found in the structure of the proximal cavity of the alpha-chain of Hb 1, although an altered distal histidyl and heme position was identified in the models of the beta-chain, possibly facilitated by a more open heme pocket due to reduced steric constraints on the vinyl substituent groups. This conformation may lead to the hemichrome form identified by spectroscopy in the Met state, which likely fulfils a potentially important physiological role.