DISENTANGLING THE EFFECTS OF KEY INNOVATIONS ON THE DIVERSIFICATION OF BROMELIOIDEAE (BROMELIACEAE)

The evolution of key innovations, novel traits that promote diversification, is often seen as major driver for the unequal distribution of species richness within the tree of life. In this study, we aim to determine the factors underlying the extraordinary radiation of the subfamily Bromelioideae, one of the most diverse clades among the neotropical plant family Bromeliaceae. Based on an extended molecular phylogenetic data set, we examine the effect of two putative key innovations, that is, the Crassulacean acid metabolism (CAM) and the water‐impounding tank, on speciation and extinction rates. To this aim, we develop a novel Bayesian implementation of the phylogenetic comparative method, binary state speciation and extinction, which enables hypotheses testing by Bayes factors and accommodates the uncertainty on model selection by Bayesian model averaging. Both CAM and tank habit were found to correlate with increased net diversification, thus fulfilling the criteria for key innovations. Our analyses further revealed that CAM photosynthesis is correlated with a twofold increase in speciation rate, whereas the evolution of the tank had primarily an effect on extinction rates that were found five times lower in tank‐forming lineages compared to tank‐less clades. These differences are discussed in the light of biogeography, ecology, and past climate change.     

The G protein-coupled receptor GPR162 is widely distributed in the CNS and highly expressed in the hypothalamus and in hedonic feeding areas

The Rhodopsin family is a class of integral membrane proteins belonging to G protein-coupled receptors (GPCRs). To date, several orphan GPCRs are still uncharacterized and in this study we present an anatomical characterization of the GPR162 protein and an attempt to describe its functional role. Our results show that GPR162 is widely expressed in GABAergic as well as other neurons within the mouse hippocampus, whereas extensive expression is observed in areas related to energy homeostasis and hedonic feeding such as hypothalamus, amygdala and ventral tegmental area, regions known to be involved in the regulation of palatable food consumption.     

Statistical Evaluation of Toxicological Experimental Design for Bayesian Model Averaged Benchmark Dose Estimation with Dichotomous Data

A method is presented to statistically evaluate toxicity study design for dose– response assessment aimed at minimizing the uncertainty in resulting Benchmark dose (BMD) estimates. Although the BMD method has been accepted as a valuable tool for risk assessment, the traditional no observed adverse effect level (NOAEL)/lowest observed adverse effective level (LOAEL) approach is still the principal basis for toxicological study design. To develop similar protocols for experimental design for BMD estimation, methods are needed that account for variability in experimental outcomes, and uncertainty in dose–response model selection and model parameter estimates. Based on Bayesian model averaging (BMA) BMD estimation, this study focuses on identifying the study design criteria that can reduce the uncertainty in BMA BMD estimates by using a Monte Carlo pre-posterior analysis on BMA BMD predictions. The results suggest that (1) as more animals are tested there is less uncertainty in BMD estimates; (2) one relatively high dose is needed and other doses can then be appropriately spread over the resulting dose scale; (3) placing different numbers of animals in different dose groups has very limited influence on improving BMD estimation; and (4) when the total number of animals is fixed, using more (but smaller) dose groups is a preferred strategy.     

Profiling CD antigens on leukaemias with an antibody microarray

Cluster of differentiation (CD) antigens are defined when a surface molecule found on some members of a standard panel of human cells reacts with at least one novel antibody, and there is good accompanying molecular data. Monoclonal antibodies to surface CD antigens on leukocytes have been used for flow cytometry, and more recently to construct microarrays that capture live cells. These DotScan^TM microarrays enable the rapid and highly parallel characterization of repertoires of CD antigens whose expression patterns may be correlated with discrete leukaemia subtypes, or used to define biomarker ‘signatures’ for non-hematological diseases. DotScan^TM with fluorescence multiplexing enables profiling of CD antigens for minor subsets of cells, such as colorectal cancer cells and tumour-infiltrating lymphocytes from a surgical sample.     

Description of Tropicibacter mediterraneus sp. nov. and Tropicibacter litoreus sp. nov.

Four strains (M15∅_3, M17^T, M49 and R37^T) were isolated from Mediterranean seawater at Malvarrosa beach, Valencia, Spain. Together with an older preserved isolate (strain 2OM6) from cultured oysters at Vinaroz, Castellón, Spain, the strains were thoroughly characterized in a polyphasic study and were placed phylogenetically within the Roseobacter clade in the family Rhodobacteraceae. Highest 16S rRNA sequence similarities of the five strains to the types of any established species corresponded to Tropicibacter multivorans (95.8–96.4%), Phaeobacter inhibens (95.9–96.3%) and Phaeobacter gallaeciensis (95.9–96.2%). On the other hand, whole genome (ANI) and protein fingerprinting (MALDI-TOF) data proved: (i) non clonality among the strains, and (ii) the existence of two genospecies, one consisting of strains M15∅_3, M17^T, M49 and 2OM6 and another one consisting of strain R37^T. Phenotypic traits determined allow differentiating both genospecies from each other and from closely related taxa. In view of all data collected we propose to accommodate these isolates in two species as members of the genus Tropicibacter, Tropicibacter mediterraneus sp. nov. (type strain M17^T = CECT 7615^T = KCTC 23058^T) and Tropicibacter litoreus sp. nov. (type strain R37^T = CECT 7639^T = KCTC 23353^T).     

The Attractive Serratia plymuthica BMA1 Strain With High Rock Phosphate-Solubilizing Activity and Its Effect on the Growth and Phosphorus Uptake by Vicia faba L. Plants

Abstract

The present work aims to investigate the attractive ability of the newly isolated bacterium Serratia plymuthica BMA1, to release phosphorus (P) from rock phosphate (RP) and also to assess its beneficial effect in promoting the growth of Vicia faba. This strain exhibited the highest RP-solubilization activity ever reported, with 450?mg l^?1 of soluble P at 30?°C. At 10 and 20?°C, its RP-solubilization was estimated at 100 and 200?mg l^?1, respectively. HPLC analysis revealed that RP-solubilizing activity was associated with the release of gluconic acid. The hydroxyapatite (HA) solubilization activity concomitantly occurred with the secretion of gluconic acid and lactic acid. Under greenhouse conditions, application of BMA1 strain as an inoculant in presence of RP as the sole P source, considerably increased phosphorus uptake by V. faba L. and upgraded its overall growth in terms of dry weight and length by 76% and 39%, respectively. This growth promoting effect was accompanied by a substantial increase in chlorophyll contents. Additionally, phosphorus levels within roots and shoots of S. plymuthica BMA1-treated plants were approximately three times greater, compared to the non-inoculated control plants. When HA was used instead of RP, bacterization with BMA1 strain also enhanced the plant growth parameters and P contents, but significantly less than RP. These findings revealed that S. plymuthica BMA1 could be a potential candidate to improve the agronomic effectiveness of RP, toward a clean P-nutrition through the formulation of bio-phosphate fertilizers for plant growth promotion.