Genetic structure and core collection of the World Olive Germplasm Bank of Marrakech: towards the optimised management and use of Mediterranean olive genetic resources

The conservation of cultivated plants in ex-situ collections is essential for the optimal management and use of their genetic resources. For the olive tree, two world germplasm banks (OWGB) are presently established, in Córdoba (Spain) and Marrakech (Morocco). This latter was recently founded and includes 561 accessions from 14 Mediterranean countries. Using 12 nuclear microsatellites (SSRs) and three chloroplast DNA markers, this collection was characterised to examine the structure of the genetic diversity and propose a set of olive accessions encompassing the whole Mediterranean allelic diversity range. We identified 505 SSR profiles based on a total of 210 alleles. Based on these markers, the genetic diversity was similar to that of cultivars and wild olives which were previously characterised in another study indicating that OWGB Marrakech is representative of Mediterranean olive germplasm. Using a model-based Bayesian clustering method and principal components analysis, this OWGB was structured into three main gene pools corresponding to eastern, central and western parts of the Mediterranean Basin. We proposed 10 cores of 67 accessions capturing all detected alleles and 10 cores of 58 accessions capturing the 186 alleles observed more than once. In each of the 10 cores, a set of 40 accessions was identical, whereas the remaining accessions were different, indicating the need to include complementary criteria such as phenotypic adaptive and agronomic traits. Our study generated a molecular database for the entire OWGB Marrakech that may be used to optimise a strategy for the management of olive genetic resources and their use for subsequent genetic and genomic olive breeding.     

The F279Y polymorphism of the <Emphasis Type="Italic">GHR</Emphasis> gene and its relation to milk production and somatic cell score in German Holstein dairy cattle

The bovine growth hormone receptor (GHR) gene has been identified as a strong positional and functional candidate gene influencing milk production. A non-synonymous single nucleotide polymorphism (SNP) in exon 8 leads to a phenylalanine to tyrosine amino acid substitution (F279Y) in the receptor. The aim of the study was to estimate the effects of the F279Y mutation on milk yield, fat, protein, casein, and lactose yield and content, as well as somatic cell score (SCS), in a German Holstein dairy cattle population. The analysis of 1,370 dairy cows confirmed a strong association of the F279Y polymorphism with milk yield, as well as with fat, protein, and casein contents. Furthermore, increasing effects on lactose yield and content for the 279Y allele were found. Even though the tyrosine variant occurred as the minor allele (16.5%), its substitution effects were 320 kg (305 d), 0.02 kg per day, and 0.07 kg per day for milk, casein, and lactose yields, respectively. The same allele had negative effects on fat, protein, and casein contents. Finally, the high-milk-yield tyrosine allele was also associated with lower SCS (p < 0.05). The data support the high potential of the F279Y polymorphism as a marker for the improvement of milk traits in selection programs.     

Miniaturized bacterial biosensor system for arsenic detection holds great promise for making integrated measurement device

Combining bacterial bioreporters with microfluidics systems holds great promise for in-field detection of chemical or toxicity targets. Recently we showed how Escherichia coli cells engineered to produce a variant of green fluorescent protein after contact to arsenite and arsenate can be encapsulated in agarose beads and incorporated into a microfluidic chip to create a device for in-field detection of arsenic, a contaminant of well known toxicity and carcinogenicity in potable water both in industrialized and developing countries. Cell-beads stored in the microfluidics chip at -20°C retained inducibility up to one month and we were able to reproducibly discriminate concentrations of 10 and 50 μg arsenite per L (the drinking water standards for European countries and the United States, and for the developing countries, respectively) from the blank in less than 200 minutes. We discuss here the reasons for decreasing bioreporter signal development upon increased storage of cell beads but also show how this decrease can be reduced, leading to a faster detection and a longer lifetime of the device.     

A rare tumor of the lung: inflammatory myofibroblastic tumor

ABSTRACT: Inflammatory myofibroblastic tumor is a rare benign lesion whose tumor origin is now proven. It represents 0.7% of all lung tumors. We report the case of a three-year-old child who suffered from a chronic cough with recurrent respiratory infections. Chest X-ray and computed tomography revealed the presence of a left lower lobe lung mass. After pneumonectomy, histological examination combined with immunohistochemical study discovered an inflammatory myofibroblastic tumor. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8722069326962972.     

Calcium signatures and signaling in cytosol and organelles of tobacco cells induced by plant defense elicitors

Calcium signatures induced by two elicitors of plant defense reactions, namely cryptogein and oligogalacturonides, were monitored at the subcellular level, using apoaequorin-transformed Nicotiana tabacum var Xanthi cells, in which the apoaequorin calcium sensor was targeted either to cytosol, mitochondria or chloroplasts. Our study showed that both elicitors induced specific Ca(2+) signatures in each compartment, with the most striking difference relying on duration. Common properties also emerged from the analysis of Ca(2+) signatures: both elicitors induced a biphasic cytosolic [Ca(2+)] elevation together with a single mitochondrial [Ca(2+)] elevation concomitant with the first cytosolic [Ca(2+)] peak. In addition, both elicitors induced a chloroplastic [Ca(2+)] elevation peaking later in comparison to cytosolic [Ca(2+)] elevation. In cryptogein-treated cells, pharmacological studies indicated that IP(3) should play an important role in Ca(2+) signaling contrarily to cADPR or nitric oxide, which have limited or no effect on [Ca(2+)] variations. Our data also showed that, depending on [Ca(2+)] fluxes at the plasma membrane, cryptogein triggered a mitochondrial respiration increase and affected excess energy dissipation mechanisms in chloroplasts. Altogether the results indicate that cryptogein profoundly impacted cell functions at many levels, including organelles.     

Phytoplankton distribution in the upwelling areas of the Moroccan Atlantic coast localized between 32°30'N and 24°N

Marine phytoplankton was studied in January and July 2002 along of four transects: 32°30′N, 29°N, 24°30′N and 24°N. A total of 142 taxa were recorded in this area. The maximal specific richness, both in summer and in winter, was registered around Dakhla (24°N). The global spatiotemporal variability of species richness and specific diversity showed that the most structured and species-rich populations are situated in the coastal areas. The vertical variation of the two parameters showed homogeneity between depth levels. The maximal phytoplanktonic densities are recorded in the southern transects due to the permanent upwelling activity in the southern Atlantic coast. The bathymetric distribution of densities was more heterogeneous during summer, characterized by a high intensity of upwelling. The species Thalassionema nitzschioides, Asterionellopsis glacialis, Melosira, Chaetoceros and Leptocylindrus minimus are indicators of upwelling.     

Metal trafficking: from maintaining the metal homeostasis to future drug design

The diverse proteins and enzymes involved in metal trafficking between and inside human cells form numerous transport networks which are highly specific for each essential metal ion and apoprotein. Individual players include voltage-gated ion channels, import and export proteins, intracellular metal-ion sensors, storage proteins and chaperones. In the case of calcium, iron and copper, some of the most apparent trafficking avenues are now well established in eukaryotes, while others are just emerging (e.g. for zinc, manganese and molybdenum). Chemistry provides an important contribution to many issues surrounding these transport pathways, from metal binding-constants and ion specificity to metal-ion exchange kinetics. Ultimately, a better understanding of these processes opens up opportunities for metal-ion-related therapy, which goes beyond traditional chelate-based metal ion detoxification.     

Phylogenetic analysis of avian infectious bronchitis virus isolates from Morocco: a retrospective study (1983 to 2014)

<正>Dear Editor,Infectious bronchitis(IB),one of the most common and difficult poultry diseases,is caused by a gammacoronavirus named infectious bronchitis virus(IBV).IBV frequently causes respiratory and/or renal diseases in chickens and egg production losses in hens.IB has a