A process-based approach to predicting the effect of climate change on the distribution of an invasive allergenic plant in Europe

Ambrosia artemisiifolia is an invasive weed in Europe with highly allergenic pollen. Populations are currently well established and cause significant health problems in the French Rhône valley, Austria, Hungary and Croatia but transient or casual introduced populations are also found in more Northern and Eastern European countries. A process-based model of weed growth, competition and population dynamics was used to predict the future potential for range expansion of A.artemisiifolia under climate change scenarios. The model predicted a northward shift in the available climatic niche for populations to establish and persist, creating a risk of increased health problems in countries including the UK and Denmark. This was accompanied by an increase in relative pollen production at the northern edge of its range. The southern European limit for A.artemisiifolia was not expected to change; populations continued to be limited by drought stress in Spain and Southern Italy. The process-based approach to modelling the impact of climate change on plant populations has the advantage over correlative species distribution models of being able to capture interactions of climate, land use and plant competition at the local scale. However, for this potential to be fully realised, additional empirical data are required on competitive dynamics of A.artemisiifolia in different crops and ruderal plant communities and its capacity to adapt to local conditions

A FTIR microspectroscopy study of the structural and biochemical perturbations induced by natively folded and aggregated transthyretin in HL-1 cardiomyocytes

Protein misfolding and aggregation are associated with a number of human degenerative diseases. In spite of the enormous research efforts to develop effective strategies aimed at interfering with the pathogenic cascades induced by misfolded/aggregated peptides/proteins, the necessary detailed understanding of the molecular bases of amyloid formation and toxicity is still lacking. To this aim, approaches able to provide a global insight in amyloid-mediated physiological alterations are of importance. In this study, we exploited Fourier transform infrared microspectroscopy, supported by multivariate analysis, to investigate in situ the spectral changes occurring in cultured intact HL-1 cardiomyocytes exposed to wild type (WT) or mutant (L55P) transthyretin (TTR) in native, or amyloid conformation. The presence of extracellular deposits of amyloid aggregates of WT or L55P TTR, respectively, is a key hallmark of two pathological conditions, known as senile systemic amyloidosis and familial amyloid polyneuropathy. We found that the major effects, associated with modifications in lipid properties and in the cell metabolic/phosphorylation status, were observed when natively folded WT or L55P TTR was administered to the cells. The effects induced by aggregates of TTR were milder and in some cases displayed a different timing compared to those elicited by the natively folded protein

A near-isogenic line (NIL) collection in diploid strawberry and its use in the genetic analysis of morphologic, phenotypic and nutritional characters

Key message: First near-isogenic line collection in diploid strawberry, a tool for morphologic, phenotypic and nutritional QTL analysis.Diploid strawberry (Fragaria vesca), with a small genome, has a high degree of synteny with the octoploid cultivated strawberry (F. × ananassa), so can be used as a simplified model for genetic analysis of the octoploid species. Agronomically interesting traits are usually inherited quantitatively and they need to be studied in large segregating progenies well characterized with molecular markers. Near-isogenic lines (NILs) are tools to dissect quantitative characters and identify some of their components as Mendelian traits. NILs are fixed homozygous lines that share the same genetic background from a recurrent parent with a single introgression region from a donor parent. Here, we developed the first NIL collection in Fragaria, with F. vesca cv. Reine des Vallées as the recurrent parent and F. bucharica as the donor parent. A collection of 39 NILs was identified using a set of single sequence repeat markers. The NILs had an average introgression of 32 cM (6 % of genome) and were phenotyped over several years in two locations. This collection segregates for agronomic characters, such as flowering, germination, fruit size and shape, and nutritional content. At least 16 QTLs for morphological and reproductive traits, such as round fruits and vegetative propagation, and seven for nutritional traits such as sugar composition and total polyphenol content, were identified. The NIL collection of F. vesca can significantly facilitate understanding of the genetics of many traits and provide insight into the more complex F. × ananassa genome.This work was funded by Grants RTA2007-00063 and AGL2010-21414 from the Spanish Ministry of Science. MU was supported by a fellowship FPI from the Spanish Ministry of Education and JB was supported by a fellowship FI from the Generalitat de Catalunya.Peer reviewe