Hereditary renal adysplasia in a three generations family.

Renal agenesia is one of the more common urinary malformations. Renal agenesia can be unilateral, more frequently, or bilateral. This malformation can be isolated or present with other urinary and/or extra urinary anomalies. We report a family with renal agenesia. The proband was a fetus. Ultrasonographic examination at 15 weeks of gestation showed a left renal agenesia and a right multicystic kidney, absence of bladder and oligohydramnios. The same features were found at 19 weeks of gestation. The couple asked for termination of pregnancy. On pathologic examination the absence of left kidney was confirmed whereas the right kidney which measured 3.5 cm was filled with numerous cysts of 0.2 cm to 1 cm. of diameter and fibrosis. According to the Potter's classification these images are characteristic of a dysplasia type II. There was no hepatic fibrosis. Family history revealed that the mother is in good health, she had previously a normal son. The father had a unilateral renal agenesia which was diagnosed after he had arterial hypertension when he was 25-years-old. The paternal grand father and his brother had unilateral renal agenesia which was shown by screening. This family shows that renal agenesia can be autosomal dominantly inherited and that the expressivity of this anomaly is variable.     

Structural constraints from residual tensorial couplings in high resolution NMR without an explicit term for the alignment tensor

Structural restraints from residual tensorial couplings in high resolution NMR are usually incorporated into molecular structure calculation programs by an energy penalty function which depends on the knowledge of the alignment tensor. Here, we show that the alignment tensor enters in linear form into such a function. Therefore, the explicit appearance of the alignment tensor can be eliminated from the penalty function. This avoids the necessity of a determination of magnitude and rhombicity of the alignment tensor in the absence of structural information. The price for this procedure is a slightly shallower energy landscape. Simulations in the vicinity of the energy minimum for the backbone of human ubiquitin show that the reduction in curvature is on the order of a few percent.     

Breaking up and making up: The secret life of the vacuolar H+‐ATPase

The vacuolar ATPase (V‐ATPase; V₁V_o‐ATPase) is a large multisubunit proton pump found in the endomembrane system of all eukaryotic cells where it acidifies the lumen of subcellular organelles including lysosomes, endosomes, the Golgi apparatus, and clathrin‐coated vesicles. V‐ATPase function is essential for pH and ion homeostasis, protein trafficking, endocytosis, mechanistic target of rapamycin (mTOR), and Notch signaling, as well as hormone secretion and neurotransmitter release. V‐ATPase can also be found in the plasma membrane of polarized animal cells where its proton pumping function is involved in bone remodeling, urine acidification, and sperm maturation. Aberrant (hypo or hyper) activity has been associated with numerous human diseases and the V‐ATPase has therefore been recognized as a potential drug target. Recent progress with moderate to high‐resolution structure determination by cryo electron microscopy and X‐ray crystallography together with sophisticated single‐molecule and biochemical experiments have provided a detailed picture of the structure and unique mode of regulation of the V‐ATPase. This review summarizes the recent advances, focusing on the structural and biophysical aspects of the field.     

A strategy for dual inhibition of the proteasome and fatty acid synthase with belactosin C-orlistat hybrids

The proteasome, a validated cellular target for cancer, is central for maintaining cellular homeostasis, while fatty acid synthase (FAS), a novel target for numerous cancers, is responsible for palmitic acid biosynthesis. Perturbation of either enzymatic machine results in decreased proliferation and ultimately cellular apoptosis. Based on structural similarities, we hypothesized that hybrid molecules of belactosin C, a known proteasome inhibitor, and orlistat, a known inhibitor of the thioesterase domain of FAS, could inhibit both enzymes. Herein, we describe proof-of-principle studies leading to the design, synthesis and enzymatic activity of several novel, β-lactone-based, dual inhibitors of these two enzymes. Validation of dual enzyme targeting through activity-based proteome profiling with an alkyne probe modeled after the most potent inhibitor, and preliminary serum stability studies of selected derivatives are also described. These results provide proof of concept for dual targeting of the proteasome and fatty acid synthase-thioesterase (FAS-TE) enabling a new approach for the development of drug-candidates with potential to overcome resistance.     

Latitudinal and altitudinal patterns of plant community diversity on mountain summits across the tropical Andes

The high tropical Andes host one of the richest alpine floras of the world, with exceptionally high levels of endemism and turnover rates. Yet, little is known about the patterns and processes that structure altitudinal and latitudinal variation in plant community diversity. Herein we present the first continental‐scale comparative study of plant community diversity on summits of the tropical Andes. Data were obtained from 792 permanent vegetation plots (1 m²) within 50 summits, distributed along a 4200 km transect; summit elevations ranged between 3220 and 5498 m a.s.l. We analyzed the plant community data to assess: 1) differences in species abundance patterns in summits across the region, 2) the role of geographic distance in explaining floristic similarity and 3) the importance of altitudinal and latitudinal environmental gradients in explaining plant community composition and richness. On the basis of species abundance patterns, our summit communities were separated into two major groups: Puna and Páramo. Floristic similarity declined with increasing geographic distance between study‐sites, the correlation being stronger in the more insular Páramo than in the Puna (corresponding to higher species turnover rates within the Páramo). Ordination analysis (CCA) showed that precipitation, maximum temperature and rock cover were the strongest predictors of community similarity across all summits. Generalized linear model (GLM) quasi‐Poisson regression indicated that across all summits species richness increased with maximum air temperature and above‐ground necromass and decreased on summits where scree was the dominant substrate. Our results point to different environmental variables as key factors for explaining vertical and latitudinal species turnover and species richness patterns on high Andean summits, offering a powerful tool to detect contrasting latitudinal and altitudinal effects of climate change across the tropical Andes.     

Biodiversity impacts from water consumption on a global scale for use in life cycle assessment

Purpose

Agriculture is a major water user worldwide, potentially depriving many ecosystems of water. Comprehensive global impact assessment methodologies are therefore required to assess impacts from water consumption on biodiversity. Since scarcity of water, as well as species richness, varies greatly between different world regions, a spatially differentiated approach is needed. Therefore, our aim is to enhance a previously published methodology in terms of spatial and species coverage.

Methods

We developed characterization factors for lifecycle impact assessment (LCIA) targeting biodiversity loss of various animal taxa (i.e., birds, reptiles, mammals, and amphibians) in wetlands. Data was collected for more than 22,000 wetlands worldwide, distinguishing between surface water- and groundwater-fed wetlands. Additionally, we account for a loss of vascular plant species in terrestrial ecosystems, based on precipitation. The characterization factors are expressed as global fractions of potential species extinctions (PDF) per cubic meter of water consumed annually and are developed with a spatial resolution of 0.05 arc degrees. Based on the geographic range of species, as well as their current threat level, as indicated by the International Union for Conservation of Nature (IUCN), we developed a vulnerability indicator that is included in the characterization factor.

Results and discussion

Characterization factors have maximal values in the order of magnitude of 10^?11 PDF·year/m³ for animal taxa combined and 10^?12 PDF·year/m³ for vascular plants. The application of the developed factors for global cultivation of wheat, maize, cotton, and rice highlights that the amount of water consumption alone is not sufficient to indicate the places of largest impacts but that species richness and vulnerability of species are indeed important factors to consider. Largest impacts are calculated for vascular plants in Madagascar, for maize, and for animal taxa; in Australia and the USA for surface water consumption (cotton); and in Algeria and Tunisia for groundwater consumption (cotton).

Conclusions

We developed a spatially differentiated approach to account for impacts from water consumption on a global level. We demonstrated its functionality with an application to a global case study of four different crops.

     

Glutathione peroxidase‐like enzymes cover five distinct cell compartments and membrane surfaces in Arabidopsis thaliana

Glutathione peroxidase‐like enzymes (GPXLs) constitute a family of eight peroxidases in Arabidopsis thaliana. In contrast to the eponymous selenocysteine glutathione peroxidases in mammalian cells that use glutathione as electron donor, GPXLs rely on cysteine instead of selenocysteine for activity and depend on the thioredoxin system for reduction. Although plant GPXLs have been implicated in important agronomic traits such as drought tolerance, photooxidative tolerance and immune responses, there remain major ambiguities regarding their subcellular localization. Because their site of action is a prerequisite for an understanding of their function, we investigated the localization of all eight GPXLs in stable Arabidopsis lines expressing N‐terminal and C‐terminal fusions with redox‐sensitive green fluorescent protein 2 (roGFP2) using confocal microscopy. GPXL1 and GPXL7 were found in plastids, while GPXL2 and GPXL8 are cytosolic nuclear. The N‐terminal target peptide of GPXL6 is sufficient to direct roGFP2 into mitochondria. Interestingly, GPXL3, GPXL4 and GPXL5 all appear to be membrane bound. GPXL3 was found exclusively in the secretory pathway where it is anchored by a single N‐terminal transmembrane domain. GPXL4 and GPXL5 are anchored to the plasma membrane. Presence of an N‐terminal myristoylation motif and genetic disruption of membrane association through targeted mutagenesis point to myristoylation as essential for membrane localization.