Evaluation of known and novel inhibitors of Orai1-mediated store operated Ca2+ entry in MDA-MB-231 breast cancer cells using a Fluorescence Imaging Plate Reader assay

The Orai1 Ca²⁺ permeable ion channel is an important component of store operated Ca²⁺ entry (SOCE) in cells. It’s over-expression in basal molecular subtype breast cancers has been linked with poor prognosis, making it a potential target for drug development. We pharmacologically characterised a number of reported inhibitors of SOCE in MDA-MB-231 breast cancer cells using a convenient Fluorescence Imaging Plate Reader (FLIPR) assay, and show that the rank order of their potencies in this assay is the same as those reported in a wide range of published assays. The assay was also used in a screening project seeking novel inhibitors. Following a broad literature survey of classes of calcium channel inhibitors we used simplified ligand structures to query the ZINC on-line database, and following two iterations of refinement selected a novel Orai1-selective dichlorophenyltriazole hit compound. Analogues of this were synthesized and evaluated in the FLIPR assay to develop structure–activity relationships (SAR) for the three domains of the hit; triazole (head), dichlorophenyl (body) and substituted phenyl (tail). For this series, the results suggested the need for a lipophilic tail domain and an out-of-plane twist between the body and tail domains.     

Angupyrones A – E, α‐Pyrone Analogues with ARE‐Activation from a Sponge‐Associated Fungus Truncatella angustata

TLC‐DPPH guided fractionation of a sponge‐associated fungus Truncatella angustata with a solid culture resulted in the isolation of five new α‐pyrone‐based analogues namely angupyrones A – E ( 1  –  5 ), and 3‐ethyl‐4‐hydroxy‐6‐methyl‐2‐pyrone. Their structures were determined on the basis of extensive spectroscopic analyses, including the modified Mosher's method, bulkiness rule, and specific rotation for the configurational assignments. Angupyrones A – E exhibited moderate antioxidant response element activation in HepG2C8 cells, while the preliminary structure‐activity relationship was discussed.     

Synthesis and anti-inflammatory structure-activity relationships of thiazine-quinoline-quinones: inhibitors of the neutrophil respiratory burst in a model of acute gouty arthritis

Sixteen new thiazine-quinoline-quinones have been synthesised, plus one bicyclic analogue. These compounds inhibited neutrophil superoxide production in vitro with IC(50)s as low 60 nM. Compounds with high in vitro anti-inflammatory activity were also tested in a mouse model of acute inflammation. The most active compounds inhibited both neutrophil infiltration and superoxide production at doses 2.5 micromol/kg, highlighting their potential for development as novel NSAIDs.     

Antifouling activity of sponge-derived polybrominated diphenyl ethers and synthetic analogues

The antifouling (AF) activity of 2-hydroxy-4-(3-hydroxy-5-methylphenoxy)- 6-methylbenozoic acid methyl ester (1), 3,5-dibromo-2-(2',4'-dibromophenoxy)phenol (2); 3,4,5-tribromo-2-(2',4'-dibromophenoxy)phenol (3), 3,4,5-tribromo-2-(2'-bromophenoxy)phenol (4), 3,5-dibromo-2(2',4'-dibromophenoxy)phenol (5), 3,4,5,6-tetrabromo-2-(2'-bromophenoxy)phenol (6); 4-phenoxyphenol (7), 4-phenoxyaniline (9), 1-chloro-4-phenoxybenzene (10); 1-bromo-4-phenoxybenzene (13) was investigated against marine bacteria, a diatom, barnacle larvae and mussel juveniles. The naturally occurring compound 2 showed the strongest AF activity in all bioassays but lacked toxicity. It inhibited the growth of all tested bacterial strains (MIC = 0.02 - 1.52 microM) and its 50% effective concentrations (EC(50)) were 0.24 microM (diatom test), 0.66 microM (mussel test) and 1.26 microM (barnacle test). Among the commercially available derivates, compound 7 was the most active in bacterial and diatom bioassays but its activity was lower than that of compound 2. Overall, the naturally occurring compounds showed stronger activity than the commercially available analogues and could be possible future non-toxic AF candidates.     

Replication of nonautonomous retroelements in soybean appears to be both recent and common

Retrotransposons and their remnants often constitute more than 50% of higher plant genomes. Although extensively studied in monocot crops such as maize (Zea mays) and rice (Oryza sativa), the impact of retrotransposons on dicot crop genomes is not well documented. Here, we present an analysis of retrotransposons in soybean (Glycine max). Analysis of approximately 3.7 megabases (Mb) of genomic sequence, including 0.87 Mb of pericentromeric sequence, uncovered 45 intact long terminal repeat (LTR)-retrotransposons. The ratio of intact elements to solo LTRs was 8:1, one of the highest reported to date in plants, suggesting that removal of retrotransposons by homologous recombination between LTRs is occurring more slowly in soybean than in previously characterized plant species. Analysis of paired LTR sequences uncovered a low frequency of deletions relative to base substitutions, indicating that removal of retrotransposon sequences by illegitimate recombination is also operating more slowly. Significantly, we identified three subfamilies of nonautonomous elements that have replicated in the recent past, suggesting that retrotransposition can be catalyzed in trans by autonomous elements elsewhere in the genome. Analysis of 1.6 Mb of sequence from Glycine tomentella, a wild perennial relative of soybean, uncovered 23 intact retroelements, two of which had accumulated no mutations in their LTRs, indicating very recent insertion. A similar pattern was found in 0.94 Mb of sequence from Phaseolus vulgaris (common bean). Thus, autonomous and nonautonomous retrotransposons appear to be both abundant and active in Glycine and Phaseolus. The impact of nonautonomous retrotransposon replication on genome size appears to be much greater than previously appreciated.     

Morphological,Bacterial, and Secondary Metabolite Changes of <Emphasis Type="Italic">Aplysina aerophoba</Emphasis> upon Long-Term Maintenance Under Artificial Conditions

The aim of this study was to analyze successional changes in the bacterial community over a period of 6 months of cultivation of Aplysina aerophoba sponges under different artificial cultivation conditions by use of denaturing gradient gel electrophoresis (DGGE). The cultivation conditions varied concerning the water temperature (20 ± 2 °C and 25 ± 2 °C) of the aquaria, additional illumination of one aquarium, and feeding of the sponges. Amplicons from DGGE separation of dominant colonizing or variably appearing bacteria were sequenced and aligned for taxonomical identification. In addition, secondary metabolites typically found in A. aerophoba were analyzed to investigate changes in the natural product profile during cultivation. The cultivation of sponges under any given condition did not lead to a depletion of their bacterial community in the course of the experiment. On the contrary, the distinctive set of associated bacteria was maintained in spite of a dramatic loss of biomass and morphological degradation during the cultivation period. Generally, all sequences obtained from the DGGE gels were related to bacteria of five phyla: Actinobacteria, Cyanobacteria, α-Proteobacteria, γ-Proteobacteria, and Chloroflexi. Despite the overall stability of the bacterial community in A. aerophoba, an unambiguous variability was detected for the Cyanobacteria “A. aerophoba clone TK09”. This variability was ascribed to the predominant light conditions. The analysis of the metabolic pattern revealed that the concentration of a class of characteristic-brominated compounds typically found in A. aerophoba, like aeroplysinin-1, aerophobin-1, aerophobin-2, and isofistularin-3, increased over the 6 months of cultivation.     

ENU Mutagenesis Reveals a Novel Phenotype of Reduced Limb Strength in Mice Lacking Fibrillin 2

Background

Fibrillins 1 (FBN1) and 2 (FBN2) are components of microfibrils, microfilaments that are present in many connective tissues, either alone or in association with elastin. Marfan''s syndrome and congenital contractural arachnodactyly (CCA) result from dominant mutations in the genes FBN1 and FBN2 respectively. Patients with both conditions often present with specific muscle atrophy or weakness, yet this has not been reported in the mouse models. In the case of Fbn1, this is due to perinatal lethality of the homozygous null mice making measurements of strength difficult. In the case of Fbn2, four different mutant alleles have been described in the mouse and in all cases syndactyly was reported as the defining phenotypic feature of homozygotes.

Methodology/Principal Findings

As part of a large-scale N-ethyl-N-nitrosourea (ENU) mutagenesis screen, we identified a mouse mutant, Mariusz, which exhibited muscle weakness along with hindlimb syndactyly. We identified an amber nonsense mutation in Fbn2 in this mouse mutant. Examination of a previously characterised Fbn2-null mutant, Fbn2^fp, identified a similar muscle weakness phenotype. The two Fbn2 mutant alleles complement each other confirming that the weakness is the result of a lack of Fbn2 activity. Skeletal muscle from mutants proved to be abnormal with higher than average numbers of fibres with centrally placed nuclei, an indicator that there are some regenerating muscle fibres. Physiological tests indicated that the mutant muscle produces significantly less maximal force, possibly as a result of the muscles being relatively smaller in Mariusz mice.

Conclusions

These findings indicate that Fbn2 is involved in integrity of structures required for strength in limb movement. As human patients with mutations in the fibrillin genes FBN1 and FBN2 often present with muscle weakness and atrophy as a symptom, Fbn2-null mice will be a useful model for examining this aspect of the disease process further.     

Avoiding a crisis of motivation for ocean management under global environmental change

Climate change and ocean acidification are altering marine ecosystems and, from a human perspective, creating both winners and losers. Human responses to these changes are complex, but may result in reduced government investments in regulation, resource management, monitoring and enforcement. Moreover, a lack of peoples’ experience of climate change may drive some towards attributing the symptoms of climate change to more familiar causes such as management failure. Taken together, we anticipate that management could become weaker and less effective as climate change continues. Using diverse case studies, including the decline of coral reefs, coastal defences from flooding, shifting fish stocks and the emergence of new shipping opportunities in the Arctic, we argue that human interests are better served by increased investments in resource management. But greater government investment in management does not simply mean more of “business‐as‐usual.” Management needs to become more flexible, better at anticipating and responding to surprise, and able to facilitate change where it is desirable. A range of technological, economic, communication and governance solutions exists to help transform management. While not all have been tested, judicious application of the most appropriate solutions should help humanity adapt to novel circumstances and seek opportunity where possible.