Proteomic analysis of phytopathogenic fungus <Emphasis Type="Italic">Botrytis cinerea</Emphasis> as a potential tool for identifying pathogenicity factors,therapeutic targets and for basic research

Botrytis cinerea is a phytopathogenic fungus causing disease in a substantial number of economically important crops. In an attempt to identify putative fungal virulence factors, the two-dimensional gel electrophoresis (2-DE) protein profile from two B. cinerea strains differing in virulence and toxin production were compared. Protein extracts from fungal mycelium obtained by tissue homogenization were analyzed. The mycelial 2-DE protein profile revealed the existence of qualitative and quantitative differences between the analyzed strains. The lack of genomic data from B. cinerea required the use of peptide fragmentation data from MALDI-TOF/TOF and ESI ion trap for protein identification, resulting in the identification of 27 protein spots. A significant number of spots were identified as malate dehydrogenase (MDH) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The different expression patterns revealed by some of the identified proteins could be ascribed to differences in virulence between strains. Our results indicate that proteomic analysis are becoming an important tool to be used as a starting point for identifying new pathogenicity factors, therapeutic targets and for basic research on this plant pathogen in the postgenomic era.     

CORAL: Building up QSAR models for the chromosome aberration test

A high level of chromosomal aberrations in peripheral blood lymphocytes may be an early marker of cancer risk, but data on risk of specific cancers and types of chromosomal aberrations are limited. Consequently, the development of predictive models for chromosomal aberrations test is important task. Majority of models for chromosomal aberrations test are so-called knowledge-based rules system. The CORAL software (http://www.insilico.eu/coral, abbreviation of “CORrelation And Logic”) is an alternative for knowledge-based rules system. In contrast to knowledge-based rules system, the CORAL software gives possibility to estimate the influence upon the predictive potential of a model of different molecular alerts as well as different splits into the training set and validation set. This possibility is not available for the approaches based on the knowledge-based rules system. Quantitative Structure–Activity Relationships (QSAR) for chromosome aberration test are established for five random splits into the training, calibration, and validation sets. The QSAR approach is based on representation of the molecular structure by simplified molecular input-line entry system (SMILES) without data on physicochemical and/or biochemical parameters. In spite of this limitation, the statistical quality of these models is quite good.     

Epiphytic fitness of a biological control agent of fire blight in apple and pear orchards under Mediterranean weather conditions

The behaviour of Pseudomonas fluorescens EPS62e was investigated in apple and pear orchards under Mediterranean climatic conditions. The trials studied the influence of weather conditions, plant host species, presence of indigenous microbial community and spread from treated to nontreated trees on colonization and survival. Population dynamics were assessed by real-time PCR and CFU-counting methods. With inoculated flowers, weather conditions were optimal for colonization, and EPS62e established high and stable population levels around 10(8) CFU per organ, according to both methods of analysis. The plant host species did not influence the colonization rate, and the biocontrol agent dominated the microbial communities of blossoms, representing up to 100% of the total cultivable population. With inoculated leaves, the EPS62e population decreased to nondetectable levels 30 days after treatment according to both methods used. EPS62e spread moderately in the orchard, being detected in nontreated flowers of trees 15-35 m from the inoculation site. The combined use of real-time PCR and CFU-counting methods of analysis permitted the identification of three physiological states for EPS62e in the field, which consisted of active colonization, survival and entry into a viable but nonculturable state, and cell death.     

High liver lipoprotein lipase activity in hyperlipemic developing rats from undernourished pregnant mothers

To study the potential relationship between circulating triacylglycerol (TAG) levels and lipoprotein lipase (LPL) activity in the newborn rat liver, pups from undernourished or normal control mothers were nursed by normal dams, and studied at 0, 1, 15 or 30 days of age. Plasma TAG levels and liver TAG concentration increased more in pups from undernourished mothers than they did in controls. At birth, liver LPL activity was similarly high in both groups but, whereas in controls it decreased progressively after birth, in pups from undernourished mothers it remained stable until 15 days of age. Results suggest that the hypertriglyceridemia present in pups from undernourished mothers may be responsible for the sustained high LPL activity in their liver which may enhance the hepatic uptake of circulating TAG.     

Tricyclic sesquiterpenes from Eremophila georgei

The structures of three new tricyclic sesquiterpenes from Eremophila georgei are described. The absolute stereochemistry of these sesquiterpenes is shown to be antipodal to that of the zizane sesquiterpenes of vetiver oil.     

Developmental Basis of Phallus Reduction during Bird Evolution

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Untangling individual variation in natural populations: ecological, genetic and epigenetic correlates of long-term inequality in herbivory

Individual variation in ecologically important features of organisms is a crucial element in ecology and evolution, yet disentangling its underlying causes is difficult in natural populations. We applied a genomic scan approach using amplified fragment length polymorphism (AFLP) markers to quantify the genetic basis of long‐term individual differences in herbivory by mammals at a wild population of the violet Viola cazorlensis monitored for two decades. In addition, methylation‐sensitive amplified polymorphism (MSAP) analyses were used to investigate the association between browsing damage and epigenetic characteristics of individuals, an aspect that has been not previously explored for any wild plant. Structural equation modelling was used to identify likely causal structures linking genotypes, epigenotypes and herbivory. Individuals of V. cazorlensis differed widely in the incidence of browsing mammals over the 20‐year study period. Six AFLP markers (1.6% of total) were significantly related to herbivory, accounting altogether for 44% of population‐wide variance in herbivory levels. MSAP analyses revealed considerable epigenetic variation among individuals, and differential browsing damage was significantly related to variation in multilocus epigenotypes. In addition, variation across plants in epigenetic characteristics was related to variation in several herbivory‐related AFLP markers. Statistical comparison of alternative causal models suggested that individual differences in herbivory are the outcome of a complex causal structure where genotypes and epigenotypes are interconnected and have direct and indirect effects on herbivory. Insofar as methylation states of MSAP markers influential on herbivory are transgenerationally heritable, herbivore‐driven evolutionary changes at the study population will involve correlated changes in genotypic and epigenotypic distributions.