Billingen (Lower Arenig/Lower Ordovician) acritarchs from the East European Platform and their palaeobiogeographic significance

Billingen (Lower Arenig/Lower Ordovician) sediments of the St. Petersburg region, northwest Russia and the Leba area, northern Poland of the East European Craton yield acritarch assemblages, which are largely homogenous though displaying minor compositional differences that probably reflect a gradient from inner to outer shelf environments. Comparison with coeval acritarch microflora from the Yangtze Platform, South China, shows an overall similarity between Baltoscandian and South Chinese phytoplankton. The widespread uniformity in the fossil microphytoplankton may be related to the extensive global 'evae' sea-level transgression, which characterized the Billingen time. This suggests that during the Tremadoc through early Arenig times, acritarch assemblages displayed essentially an undifferentiated cold-water and oceanic character along the whole margin of Perigondwana in the South, as well as on the South Chinese and Baltic platforms, at middle latitudes (Mediterranean oceanic Realm). Despite this overall similarity, however, some typical taxa of the high-latitude Mediterranean Province (Arbusculidium, Coryphidium and Striatotheca) occur in South China, but are absent in Baltica. This discrepancy is explained as caused by differences in climatic and physiographic conditions that prevailed at the two palaeocontinents at this time. The inferred pattern of oceanic circulation during the Lower Ordovician is consistent with the palynological evidence of a prevailing warmer climate in Baltica than in South China, although the two palaeocontinents occupied the same palaeolatitudinal position.     

Genome-Wide Association Mapping for Yield and Other Agronomic Traits in an Elite Breeding Population of Tropical Rice (Oryza sativa)

Genome-wide association mapping studies (GWAS) are frequently used to detect QTL in diverse collections of crop germplasm, based on historic recombination events and linkage disequilibrium across the genome. Generally, diversity panels genotyped with high density SNP panels are utilized in order to assay a wide range of alleles and haplotypes and to monitor recombination breakpoints across the genome. By contrast, GWAS have not generally been performed in breeding populations. In this study we performed association mapping for 19 agronomic traits including yield and yield components in a breeding population of elite irrigated tropical rice breeding lines so that the results would be more directly applicable to breeding than those from a diversity panel. The population was genotyped with 71,710 SNPs using genotyping-by-sequencing (GBS), and GWAS performed with the explicit goal of expediting selection in the breeding program. Using this breeding panel we identified 52 QTL for 11 agronomic traits, including large effect QTLs for flowering time and grain length/grain width/grain-length-breadth ratio. We also identified haplotypes that can be used to select plants in our population for short stature (plant height), early flowering time, and high yield, and thus demonstrate the utility of association mapping in breeding populations for informing breeding decisions. We conclude by exploring how the newly identified significant SNPs and insights into the genetic architecture of these quantitative traits can be leveraged to build genomic-assisted selection models.     

Cyrtocrinids (Echinodermata,Crinoidea) from Upper Jurassic Štramberk‐type limestones in southern Poland

Abstract: A systematic account of highly diverse cyrtocrinid faunules from Upper Jurassic strata of ?tramberk type (Oxfordian–Tithonian) in southern Poland (Polish Carpathians) is presented. Fourteen taxa (Phyllocrinus malbosianus, Ph. stellaris, Ph. sp., Psalidocrinus armatus, Sclerocrinus compressus, S. polonicus sp. nov., Hemicrinus aff. kabanovi, Ancepsicrinus parvus gen. et sp. nov., Tetracrinus baumilleri sp. nov., Eugeniacrinites alexandrowiczi, E. cf. moravicus, E. sp., Eudesicrinus gluchowskii sp. nov. and Hemibrachiocrinus tithonicus sp. nov. are described and illustrated. Representatives of the genus Eudesicrinus, previously recorded only from the Lower Jurassic, are here shown to extend into the uppermost Jurassic. Other cyrtocrinids considered are common in Jurassic/Cretaceous strata across Europe. In the present faunules, isocrinid (Isocrinida), comatulid (Comatulida) and roveacrinid (Roveacrinida sensu Rasmussen, inclusive of Saccocoma) crinoids are associated.     

The ST Pinch: A side chain-to-side chain hydrogen-bonded motif

The ST Pinch is a 12-membered hydrogen-bonded motif (Ser/Thr-Xaa-Ser/Thr) involving the side chain oxygen atoms of two Ser/Thr residues. We identified the ST Pinch in 104 proteins in a database containing high-resolution crystal structures. Conformational analysis of the ST Pinch in these proteins points to specific preferences for the Xaa residue and a high propensity of this residue to adopt positive φ angles. Our results suggest that this motif serves as a linker of secondary structural elements within proteins and is a new addition to the existing list of short hydrogen bond-stabilized motifs in proteins.     

Genetic mapping identifies a rice naringenin O-glucosyltransferase that influences insect resistance

Naringenin, the biochemical precursor for predominant flavonoids in grasses, provides protection against UV damage, pathogen infection and insect feeding. To identify previously unknown loci influencing naringenin accumulation in rice (Oryza sativa), recombinant inbred lines derived from the Nipponbare and IR64 cultivars were used to map a quantitative trait locus (QTL) for naringenin abundance to a region of 50 genes on rice chromosome 7. Examination of candidate genes in the QTL confidence interval identified four predicted uridine diphosphate-dependent glucosyltransferases (Os07g31960, Os07g32010, Os07g32020 and Os07g32060). In vitro assays demonstrated that one of these genes, Os07g32020 (UGT707A3), encodes a glucosyltransferase that converts naringenin and uridine diphosphate-glucose to naringenin-7-O-β-d -glucoside. The function of Os07g32020 was verified with CRISPR/Cas9 mutant lines, which accumulated more naringenin and less naringenin-7-O-β-d -glucoside and apigenin-7-O-β-d -glucoside than wild-type Nipponbare. Expression of Os12g13800, which encodes a naringenin 7-O-methyltransferase that produces sakuranetin, was elevated in the mutant lines after treatment with methyl jasmonate and insect pests, Spodoptera litura (cotton leafworm), Oxya hyla intricata (rice grasshopper) and Nilaparvata lugens (brown planthopper), leading to a higher accumulation of sakuranetin. Feeding damage from O. hyla intricata and N. lugens was reduced on the Os07g32020 mutant lines relative to Nipponbare. Modification of the Os07g32020 gene could be used to increase the production of naringenin and sakuranetin rice flavonoids in a more targeted manner. These findings may open up new opportunities for selective breeding of this important rice metabolic trait.     

Pharmacology and cell biology of the bombesin receptor subtype 4 (BB4-R).

Recently, a fourth member of the bombesin (Bn) receptor family (fBB4-R) was isolated from a cDNA library from the brain of the frog, Bombina orientalis. Its pharmacology and cell biology are largely unknown, and no known natural cell lines or tissues possess sufficient numbers of fBB4-R's to allow either of these to be determined. To address these issues, we have used three different strategies. fBB4-R expression in cells widely used for other Bn receptor subtypes was unsuccessful as was expression in two frog cell lines. However, stable fBB4-R cell lines were obtained in CHO-K1 cells which were shown to faithfully demonstrate the correct pharmacology of the related Bn receptor, the GRP receptor, when expressed in these cells. [DPhe6,betaAla11,Phe13,Nle14]Bn(6-14) was found to have high affinity (Ki = 0.4 nM) for the fBB4 receptor and 125I-[DTyr6,betaala11,Phe13,Nle14]Bn(6-14) to be an excellent ligand for this receptor. The fBB4-R had a unique pharmacology for naturally occurring Bn-related agonists, with the presence of a penultimate phenylalanine being critical for high-affinity interaction. It also had a unique profile for six classes of Bn antagonists. The fBB4-R was coupled to phospholipase C with activation increasing [3H]inositol phosphates and mobilizing Ca2+ almost entirely from cellular sources. There was a close correlation between agonist the receptor occupation and the receptor activation. Three of the five classes of Bn receptor antagonists that interacted with higher affinity with the fBB4-R functioned as fBB4-R antagonists and two as partial agonists. fBB4-R activation stimulated increases in phospholipase D (PLD) over the same range of concentrations at which it activated phospholipase C. These results demonstrate that the fBB4 receptor has a unique pharmacology for agonists and antagonists and is coupled to phospholipase C and D. The availability of these cell lines, this novel ligand, and the identification of three classes of antagonists that can be used as lead compounds should facilitate the further investigation of the pharmacology and cell biology of the BB4 receptor.     

Role of regulatory agencies

In this paper the authors discuss the role of regulation in assuring blood safety. After an overview of the subject by a leading expert, examples are provided of regulatory systems for blood transfusion services in several countries and regions. Additionally, the perspective of WHO is given on the essential role of national regulatory authorities in assuring the quality of national blood programmes.Collectively, the sections of this paper afford an opportunity for readers to make comparisons among different regulatory frameworks and to "benchmark" among the existing systems. Despite many differences in approach, a clear pattern emerges of worldwide efforts to strengthen blood regulatory systems.