University of Basel

About: University of Basel is a education organization based out in Basel, Basel-Stadt, Switzerland. It is known for research contribution in the topics: Population & Gene. The organization has 25084 authors who have published 52975 publications receiving 2388002 citations. The organization is also known as: Universität Basel & Basel University.

The variability of stomatal sensitivity to leaf water potential across tree species indicates a continuum between isohydric and anisohydric behaviours

Abstract: Summary The relationship between stomatal conductance (gs) and leaf water potential (Ψl) is key to the understanding of plant function under changing climate. The variability among tree species gave rise to selection towards either of two contrasting water management types: isohydric or anisohydric. This study explores the variability of gs to Ψl across tree species. Curves of gs(Ψl) were collected from the scientific literature for 70 woody plant species. The data set is comprised of angiosperm and gymnosperm species from all major forest biomes. The hypothesis that curves from different tree species diverge between isohydric and anisohydric behaviours was tested. Species-specific curves formed a continuum, rather than dichotomy between isohydric and anisohydric, as confirmed by distribution models. Alternatively, the water potential at 50% of the maximum gs (Ψgs50) was used to quantitatively compare between species. A major difference emerged among xylem anatomy classes whereby ring-porous species had higher absolute gs at Ψl < −2 MPa than diffuse-porous and coniferous species. A positive, linear correlation was shown between Ψgs50 and Ψl at 50% loss of xylem conductivity. The results suggest that stomatal sensitivity to leaf water potential strongly relates to xylem characteristics. The use of Ψgs50 offers a quantitative alternative to the current, yet biased, distinction between isohydric and anisohydric species.

Midbrain circuits for defensive behaviour

Abstract: Survival in threatening situations depends on the selection and rapid execution of an appropriate active or passive defensive response, yet the underlying brain circuitry is not understood. Here we use circuit-based optogenetic, in vivo and in vitro electrophysiological, and neuroanatomical tracing methods to define midbrain periaqueductal grey circuits for specific defensive behaviours. We identify an inhibitory pathway from the central nucleus of the amygdala to the ventrolateral periaqueductal grey that produces freezing by disinhibition of ventrolateral periaqueductal grey excitatory outputs to pre-motor targets in the magnocellular nucleus of the medulla. In addition, we provide evidence for anatomical and functional interaction of this freezing pathway with long-range and local circuits mediating flight. Our data define the neuronal circuitry underlying the execution of freezing, an evolutionarily conserved defensive behaviour, which is expressed by many species including fish, rodents and primates. In humans, dysregulation of this 'survival circuit' has been implicated in anxiety-related disorders.

Genome-wide association study identifies eight risk loci and implicates metabo-psychiatric origins for anorexia nervosa

Abstract: Characterized primarily by a low body-mass index, anorexia nervosa is a complex and serious illness1, affecting 0.9-4% of women and 0.3% of men2-4, with twin-based heritability estimates of 50-60%5. Mortality rates are higher than those in other psychiatric disorders6, and outcomes are unacceptably poor7. Here we combine data from the Anorexia Nervosa Genetics Initiative (ANGI)8,9 and the Eating Disorders Working Group of the Psychiatric Genomics Consortium (PGC-ED) and conduct a genome-wide association study of 16,992 cases of anorexia nervosa and 55,525 controls, identifying eight significant loci. The genetic architecture of anorexia nervosa mirrors its clinical presentation, showing significant genetic correlations with psychiatric disorders, physical activity, and metabolic (including glycemic), lipid and anthropometric traits, independent of the effects of common variants associated with body-mass index. These results further encourage a reconceptualization of anorexia nervosa as a metabo-psychiatric disorder. Elucidating the metabolic component is a critical direction for future research, and paying attention to both psychiatric and metabolic components may be key to improving outcomes.

Trehalose in yeast, stress protectant rather than reserve carbohydrate

Abstract: Trehalose and glycogen are generally regarded as the two main reserve carbohydrates in yeast. However, several lines of evidence suggest that trehalose does not primarily function as a reserve but as a highly efficient protecting agent to maintain structural integrity of the cytoplasm under environmental stress conditions.