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Predicting likely species responses to an alteration of their local environment is key to decision‐making in resource management, ecosystem restoration and biodiversity conservation practice in the face of global human‐induced habitat disturbance. This is especially true for forest trees which are a dominant life form on Earth and play a central role in supporting diverse communities and structuring a wide range of ecosystems. In Europe, it is expected that most forest tree species will not be able to migrate North fast enough to follow the estimated temperature isocline shift given current predictions for rapid climate warming. In this context, a topical question for forest genetics research is to quantify the ability for tree species to adapt locally to strongly altered environmental conditions (Kremer et al. ). Identifying environmental factors driving local adaptation is, however, a major challenge for evolutionary biology and ecology in general but is particularly difficult in trees given their large individual and population size and long generation time. Empirical evaluation of local adaptation in trees has traditionally relied on fastidious long‐term common garden experiments (provenance trials) now supplemented by reference genome sequence analysis for a handful of economically valuable species. However, such resources have been lacking for most tree species despite their ecological importance in supporting whole ecosystems. In this issue of Molecular Ecology, De Kort et al. () provide original and convincing empirical evidence of local adaptation to temperature in black alder, Alnus glutinosa L. Gaertn, a surprisingly understudied keystone species supporting riparian ecosystems. Here, De Kort et al. () use an innovative empirical approach complementing state‐of‐the‐art landscape genomics analysis of A. glutinosa populations sampled in natura across a regional climate gradient with phenotypic trait assessment in a common garden experiment (Fig. ). By combining the two methods, De Kort et al. () were able to detect unequivocal association between temperature and phenotypic traits such as leaf size as well as with genetic loci putatively under divergent selection for temperature. The research by De Kort et al. () provides valuable insight into adaptive response to temperature variation for an ecologically important species and demonstrates the usefulness of an integrated approach for empirical evaluation of local adaptation in nonmodel species (Sork et al. ).

A monokaryotic strain of the white-rot fungus Pycnoporus cinnabarinus was shown to produce, in a 2-L bioreactor culture, 100 mg·L-1 benzaldehyde (bitter almond aroma) from L-phenylalanine with a productivity of 33 mg·L-1·day-1. The addition of HP20 resin, a styrene divinylbenzene copolymer highly selective for benzaldehyde, enabled an eightfold increase in the production of benzaldehyde and a twofold increase in productivity. In the presence of HP20 resin, the production of 790 mg·L-1 benzaldehyde was concomitant with the synthesis of cinnamic acid derivatives of high organoleptic notes such as cinnamaldehyde, cinnamyl alcohol, and methyl cinnamate.Key words : benzaldehyde, L-phenylalanine, Pycnoporus cinnabarinus, adsorbents.

Our previous studies showed that prenatal ethanol exposure (PEE) elevated blood total cholesterol (TCH) level in adult offspring rats. This study was aimed at elucidating the intrauterine programming mechanism of hypercholesterolemia in adult rats induced by PEE. Pregnant Wistar rats were intragastrically administered ethanol (4 mg/kg∙d) from gestational day (GD) 9 to 20. The offspring rats were euthanized at GD20 and postnatal week 24. Results showed that PEE decreased serum TCH and HDL-C levels (female and male) as well as LDL-C level (female only) in fetal rats but increased serum TCH level and the TCH/HDL-C and LDL-C/HDL-C ratios in adult rats. Furthermore, PEE elevated serum corticosterone levels but inhibited hepatic insulin-like growth factor 1 (IGF1) signaling pathway, cholesterol synthesis and output in fetal rats. The conversed changes were observed in adult rats. Moreover, histone acetylation (H3K9ac and H3K14ac) and expression of hepatic reverse cholesterol transport (RCT) related genes, scavenger receptor BI and low-density lipoprotein receptor were decreased before and after birth by PEE. In HepG2 cells, cortisol negatively regulated the IGF1 signaling pathway and cholesterol metabolic genes, but this inhibition of the cholesterol metabolic genes could be reversed by glucocorticoid receptor antagonist RU486, whereas exogenous IGF1 treatment only reversed the downregulation of RCT genes by cortisol. We confirmed a "two programming" mechanism for PEE-induced hypercholesterolemia in adult rats. The "first programming" was a glucocorticoid (GC)-induced persistent reduction of RCT genes by epigenetic modifications, and the "second programming" was the negative regulation of cholesterol synthesis and output by the GC-IGF1 axis.

Understanding the genetic bases underlying climate adaptation is a key element to predict the potential of species to face climate warming. Although substantial climate variation is observed at a micro-geographic scale, most genomic maps of climate adaptation have been established at broader geographical scales. Here, by using a Pool-Seq approach combined with a Bayesian hierarchical model that control for confounding by population structure, we performed a genome-environment association (GEA) analysis to investigate the genetic basis of adaptation to six climate variables in 168 natural populations of Arabidopsis thaliana distributed in south-west of France. Climate variation among the 168 populations represented up to 24% of climate variation among 521 European locations where A. thaliana inhabits. We identified neat and strong peaks of association, with most of the associated SNPs being significantly enriched in likely functional variants and/or in the extreme tail of genetic differentiation among populations. Furthermore, genes involved in transcriptional mechanisms appear predominant in plant functions associated with local climate adaptation. Globally, our results suggest that climate adaptation is an important driver of genomic variation in A. thaliana at a small spatial scale and mainly involves genome-wide changes in fundamental mechanisms of gene regulation. The identification of climate-adaptive genetic loci at a micro-geographic scale also highlights the importance to include within-species genetic diversity in ecological niche models for projecting potential species distributional shifts over short geographic distances.

Water use efficiency (WUE) is a quantitative measurement which improvement is a major issue in the context of global warming and restrictions in water availability for agriculture. In this study, we aimed at studying the variation and genetic control of WUE and the respective role of its components (plant biomass and transpiration) in a perennial fruit crop. We explored an INRA apple core collection grown in a phenotyping platform to screen one-year-old scions for their accumulated biomass, transpiration and WUE under optimal growing conditions. Plant biomass was decompose into morphological components related to either growth or organ expansion. For each trait, nine mixed models were evaluated to account for the genetic effect and spatial heterogeneity inside the platform. The Best Linear Unbiased Predictors of genetic values were estimated after model selection. Mean broad-sense heritabilities were calculated from variance estimates. Heritability values indicated that biomass (0.76) and WUE (0.73) were under genetic control. This genetic control was lower in plant transpiration with an heritability of 0.54. Across the collection, biomass accounted for 70% of the WUE variability. A Hierarchical Ascendant Classification of the core collection indicated the existence of six groups of genotypes with contrasting morphology and WUE. Differences between morphotypes were interpreted as resulting from differences in the main processes responsible for plant growth: cell division leading to the generation of new organs and cell elongation leading to organ dimension. Although further studies will be necessary on mature trees with more complex architecture and multiple sinks such as fruits, this study is a first step for improving apple plant material for the use of water.

A mathematical simulation method was developed for visualization of the diffuse reflected light on a surface of 3-layered models of urinary bladder wall. Five states, from normal to precancerous, of the urinary bladder epithelium were simulated. With the use of solutions of classical electrodynamics equations, scattering coefficientsμsand asymmetry parametersgof the bladder epithelium were found in order to perform Monte Carlo calculations. The results, compared with the experimental studies, has revealed the influence of the changes in absorption and scattering properties on diffuse-reflectance signal distributions on the surfaces of the modelled media.