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The rising demand for powerful oncolytic virotherapy agents has led to the identification of Maraba virus, one of the most potent oncolytic viruses from Rhabdoviridae family which displays high selectivity for killing malignant cells and low cytotoxicity in normal cells. Although the virus is readied to be used for clinical trials, the interactions between the virus and the host cells is still unclear. Using a newly developed interferon-sensitive mutant Maraba virus (MG1), we have identified two key regulators of global translation (4E-BP1 and eIF2&alpha, ) as being involved in the regulation of protein synthesis in the infected cells. Despite the translational arrest upon viral stress, we showed an up-regulation of anti-apoptotic Bcl-xL protein that provides a survival benefit for the host cell, yet facilitates effective viral propagation. Given the fact that eIF5B canonically regulates 60S ribosome subunit end joining and is able to replace the role of eIF2 in delivering initiator tRNA to the 40S ribosome subunit upon the phosphorylation of eIF2&alpha, we have tested whether eIF5B mediates the translation of target mRNAs during MG1 infection. Our results show that the inhibition of eIF5B significantly down-regulates the level of Bcl-xL steady-state mRNA, thus indirectly attenuates viral propagation.

Genome-wide association studies for plasma triglycerides and hepatic steatosis identified a risk locus on chromosome 8q24 close to the TRIB1 gene, encoding Tribbles Pseudokinase 1 (TRIB1). In previous studies conducted in murine models, hepatic over-expression of Trib1 was shown to increase fatty acid oxidation and decrease triglyceride synthesis whereas Trib1 knockdown mice exhibited hypertriglyceridemia. Here we have examined the impact of TRIB1 suppression in human and mouse hepatocytes. Examination of a panel of lipid regulator transcripts revealed species-specific effects, prompting us to focus on human models for the remainder of the study. Acute knockdown of TRIB1 in human primary hepatocytes resulted in decreased expression of MTTP and APOB, required for very low density lipoprotein (VLDL) assembly although particle secretion was not significantly affected. A parallel analysis performed in HepG2 revealed reduced MTTP, but not APOB, protein as a result of TRIB1 suppression. Global gene expression changes of human primary hepatocytes upon TRIB1 suppression were analyzed by clustering algorithms and found to be consistent with dysregulation of several pathways fundamental to liver function, including altered CEBPA and B transcript levels and impaired glucose handling. Indeed, TRIB1 expression in HepG2 cells was found to be inversely proportional to glucose concentration. Lastly TRIB1 downregulation in primary hepatocytes was associated with suppression of the HNF4A axis. In HepG2 cells, TRIB1 suppression resulted in reduced HNF4A protein levels while HNF4A suppression increased TRIB1 expression. Taken together these studies reveal an important role for TRIB1 in human hepatocyte biology.

// Urszula Liwak-Muir 1 , Christine C. Dobson 1 , Thet Naing 1 , Quinlan Wylie 1 , Lucia Chehade 1 , Stephen D. Baird 1 , Pranesh K. Chakraborty 2,3 and Martin Holcik 1,2 1 Molecular Biomedicine Program, Children’s Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada 2 Department of Pediatrics, University of Ottawa, Ottawa, ON, Canada 3 Newborn Screening Ontario, Children’s Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada Correspondence to: Martin Holcik, email: // Keywords : tumour supressor, miRNA, kinase Received : September 14, 2015 Accepted : November 16, 2015 Published : November 22, 2015 Abstract Programmed cell death 4 (PDCD4) is a tumour suppressor implicated in cancer development and progression and was recently identified as a repressor of cap-independent translation of specific genes involved in the regulation of apoptosis. We show that the RNA-binding protein HuR binds to the PDCD4 3’UTR to protect it from miR-21-induced silencing. However, following H 2 O 2 treatment, PDCD4 mRNA is degraded via miR-21 binding. Importantly, we identify HuR as a novel substrate of the ERK8 kinase pathway in response to H 2 O 2 treatment. We show that phosphorylation of HuR by ERK8 prevents it from binding to PDCD4 mRNA and allows miR-21-mediated degradation of PDCD4.

The presence of acetic acid during industrial alcohol fermentation reduces the yield of fermentation by imposing additional stress on the yeast cells. The biology of cellular responses to stress has been a subject of vigorous investigations. Although much has been learned, details of some of these responses remain poorly understood. Members of heat shock chaperone HSP proteins have been linked to acetic acid and heat shock stress responses in yeast. Both acetic acid and heat shock have been identified to trigger different cellular responses including reduction of global protein synthesis and induction of programmed cell death. Yeast HSC82 and HSP82 code for two important heat shock proteins that together account for 1-2% of total cellular proteins. Both proteins have been linked to responses to acetic acid and heat shock. In contrast to the overall rate of protein synthesis which is reduced, the expression of HSC82 and HSP82 is induced in response to acetic acid stress. In the current study we identified two yeast genes DOM34 and RPL36A that are linked to acetic acid and heat shock sensitivity. We investigated the influence of these genes on the expression of HSP proteins. Our observations suggest that Dom34 and RPL36A influence translation in a CAP-independent manner., This work was funded by the Natural Sciences and Engineering Research Council of Canada, NSERC., info:eu-repo/semantics/publishedVersion

The TRIB1 locus (8q24.13) is a novel locus identified and replicated by several genome-wide association studies for associations with plasma triglycerides, apolipoprotein B and coronary artery disease. The TRIB1 protein product, tribbles-like protein 1 (Trib1), regulates MAPK activity. MAP kinases transduce a large variety of external signals, leading to a wide range of cellular responses, including growth, differentiation, inflammation and apoptosis. Importantly, Trib1 has been shown to regulate hepatic lipogenesis and very low density lipoprotein production. Despite the relevance of hepatocyte Trib1 to lipid metabolism and atherosclerosis, little is known about the mechanisms regulating Trib1 itself. Here, we identify the mitochondria axis as a regulator of Trib1. Treatment of HepG2 cells with a short pulse of a low oligomycin concentration led to a potent and prolonged increase in the Trib1 mRNA, an effect that was shared with other mitochondria stressors. HuH7 cells as well murine hepatocytes were also responsive albeit to a weaker extent. The upregulation appeared largely independent of reactive oxygen species generation or metabolic stress and was mainly under transcriptional control, with ERK1/2 playing an important regulating role in the process. While the presence of the Trib1 protein could be inferred, attempts to correlate the increased mRNA to changes in protein level were unsuccessful due to the lack of recognizable Trib1 signal. Our data enrich the current paradigm of Trib1 as an activator of the MAPK pathway by uncovering a role for MAPK in regulating Trib1.

Pathogenic bacteria secrete various virulence factors, including toxins, lipases and proteases that allow them to infect, breakdown and colonize host tissue. Among various modes of action that the pathogenic bacteria use to damage the host, pore formation (by pore forming toxins (PFTs)) and lipid hydrolysis (by phospholipases) modes are common in damaging the eukaryotic cell membrane. PFTs in their monomeric form are extracellular diffusible and able to form hydrophilic pores in cell membrane while phospholipases cleaves and hydrolyzes the ester bonds of most phospholipids in cell membrane. Both modes of action cause uncontrolled permeation of ions and molecules across cell membrane, leading to cell death by apoptosis or necrosis. In this work, the toxins secreted by two clinically important human pathogens, methicillin susceptible Staphylococcus aureus (MSSA476) and Pseudomonas aeruginosa (PAO1) were studied via their interaction with a planar tethered bilayer lipid membrane (pTBLM) using surface plasmon resonance spectroscopy (SPR) and electrochemical impedance spectroscopy (EIS). Detection and discrimination is based on lipid-loss (lipid hydrolysis by phospholipases) or non lipid-loss (pore formation by PFTs) from pTBLM upon interaction with supernatant of pathogenic bacteria. Using EIS and SPR, it is demonstrated that major toxins of S. auerus are PFTs while most of toxin associated with P. aeruginosa are more lipid damaging lipolytic enzymes. Such a format might have future utility as a simple assay for measuring the presence membrane lytic virulence factors in clinical samples.

We describe a snub-nosed monkey that is new to science from the high altitudes of northeastern Kachin state, northeastern Myanmar, the Burmese snub-nosed monkey, Rhinopithecus strykeri sp. nov. Descriptions are based on a skin and skulls of four specimens obtained from local hunters. The new species is geographically isolated from other snub-nosed monkeys and separated from them by two major barriers—the Mekong and the Salween (Thanlwin) rivers. The species is chiefly diagnosed by its almost entirely blackish fur coloration with white fur only on ear tufts, chin beard, and perineal area, and its relatively long tail (140% of head and body length in the adult male). Preliminary surveys and interviews with hunters indicate that the new species is limited in distribution to the Maw River area, a small region of the Salween-N'mai Hka divide in northeastern Kachin state, northeastern Myanmar. The distribution area appears to cover about 270 km2, and the species may consist of only three groups with a total population of approximately 260–330 individuals. Our data on hunting pressure suggest that the species is Critically Endangered. Am. J. Primatol. 73:96–107, 2011. © 2010 Wiley-Liss, Inc.

Heavy metal and metalloid contaminations are among the most concerning types of pollutant in the environment. Consequently, it is important to investigate the molecular mechanisms of cellular responses and detoxification pathways for these compounds in living organisms. To date, a number of genes have been linked to the detoxification process. The expression of these genes can be controlled at both transcriptional and translational levels. In baker’s yeast,Saccharomyces cerevisiae, resistance to a wide range of toxic metals is regulated by glutathione S-transferases. YeastURE2encodes for a protein that has glutathione peroxidase activity and is homologous to mammalian glutathione S-transferases. TheURE2expression is critical to cell survival under heavy metal stress. Here, we report on the finding of two genes,ITT1, an inhibitor of translation termination, andRPS1A, a small ribosomal protein, that when deleted yeast cells exhibit similar metal sensitivity phenotypes to gene deletion strain forURE2. Neither of these genes were previously linked to metal toxicity. Our gene expression analysis illustrates that these two genes affectURE2mRNA expression at the level of translation.Summary statementWe identified two yeast genes,ITT1andRPS1A, that when deleted, results in yeast cells sensitivity to heavy metals and metalloids. Further investigation indicated that they influence the expression ofURE2gene, a key player in metal detoxification, by upregulating its translation. Our findings suggest thatITT1andRPS1Aplay an indirect role in responding to toxic metal stress.

Objectives— We have investigated the functional significance of conserved sequences within the 9p21.3 risk locus for coronary artery disease (CAD) and determined the relationship of 9p21.3 to expression of ANRIL and to whole genome gene expression. Methods and Results— We demonstrate that a conserved sequence within the 9p21.3 locus has enhancer activity and that the risk variant significantly increases reporter gene expression in primary aortic smooth muscle cells. Whole blood RNA expression of the short variants of ANRIL was increased by 2.2-fold whereas expression of the long ANRIL variant was decreased by 1.2-fold in healthy subjects homozygous for the risk allele. Expression levels of the long and short ANRIL variants were positively correlated with that of the cyclin-dependent kinase inhibitor, CDKN2B ( p15 ) and TDGF1 ( Cripto ), respectively. Relevant to atherosclerosis, genome-wide expression profiling demonstrated upregulation of gene sets modulating cellular proliferation in carriers of the risk allele. Conclusion— These findings are consistent with the hypothesis that the 9p21.3 risk allele contains a functional enhancer, the activity of which is altered in carriers of the risk allele. 9p21.3 may promote atherosclerosis by regulating expression of ANRIL , which in turn is associated with altered expression of genes controlling cellular proliferation pathways.

Scavenger receptor class B type I (SR-BI) has an established role in mediating the selective uptake of choles- terol from HDL in hepatocytes, steroidogenic cells, and other tissues. SR-BI is present on the plasma membrane but also localizes to stable intracellular compartments of unknown function. Using indirect immunofluorescence and subcellular fractionation, we have investigated the subcellular distribu- tion of SR-BI. We report that red fluorescent protein-tagged mouse SR-BI (RFP-mSR-BI) colocalizes with the late endo- somal and lysosomal markers, Rab7, LBPA, and Rab9. In ad- dition, endogenous SR-BI is also found on lysosomes and colocalizes with LAMP-2 in primary hepatocytes. Further- more, we demonstrate that the trafficking of SR-BI through these compartments is Rab7 dependent. Interestingly, filipin staining indicates accumulation of lysosomal cholesterol in SR-BI-deficient ( 2/2 ) as compared with wild-type hepato- cytes. In addition to its role as a plasma membrane receptor, SR-BI may function in cholesterol trafficking from late endo- somes/lysosomes.—Ahras, M., T. Naing, and R. McPherson. Scavenger receptor class B type I localizes to a late endosomal compartment. J. Lipid Res. 2008. 49: 1569-1576.

Age-related macular degeneration (AMD) is a major cause of blindness, but presents differently in Europeans and Asians. Here, we perform a genome-wide and exome-wide association study on 2, 119 patients with exudative AMD and 5, 691 controls, with independent replication in 4, 226 patients and 10, 289 controls, all of East Asian descent, as part of The Genetics of AMD in Asians (GAMA) Consortium. We find a strong association between CETP Asp442Gly (rs2303790), an East Asian-specific mutation, and increased risk of AMD (odds ratio (OR)=1.70, P=5.60 × 10[-22]). The AMD risk allele (442Gly), known to protect from coronary heart disease, increases HDL cholesterol levels by 0.17mmoll-1 (P=5.82 × 10[-21]) in East Asians (n=7, 102). We also identify three novel AMD loci: C6orf223 Ala231Ala (OR=0.78, P=6.19 × 10[-18]), SLC44A4 Asp47Val (OR=1.27, P=1.08 × 10[-11]) and FGD6 Gln257Arg (OR=0.87, P=2.85 × 10[-8]). Our findings suggest that some of the genetic loci conferring AMD susceptibility in East Asians are shared with Europeans, yet AMD in East Asians may also have a distinct genetic signature., 加齢黄斑変性の発症に関わるアジア人特有の遺伝子変異を発見. 京都大学プレスリリース. 2015-02-05., Updated 30 March 2015. [Corrigendum] doi:10.1038/ncomms7817

A new methodology for detecting the microbiological state of a wound dressing in terms of its colonization with pathogenic bacteria such as Staphylococcus aureus or Pseudomonas aeruginosa has been developed. Here we report how stabilized lipid vesicles containing self-quenched carboxyfluorescein dye are sensitive to lysis only by toxins/virulence factors from P. aeruginosa and S. aureus but not by a non-toxic Escherichia coli species. The development of the stabilized vesicles is discussed and their response to detergent (triton), bacterial toxin (α-hemolysin) and lipases (phospholipase A 2). Finally, fabrics with stabilized vesicles attached via plasma deposited maleic anhydride coupling are shown visibly responding to S. aureus (MSSA 476) and P. aeruginosa (PAO1) but not E. coli DH5α in a prototype dressing. Refereed/Peer-reviewed

Common intronic SNPs in the human fat mass and obesity associated (FTO) gene are strongly associated with body mass index (BMI). In mouse models, inactivation of the Fto gene results in a lean phenotype, whereas overexpression of Fto leads to increased food intake and obesity. The latter finding suggests that copy number variants at the FTO locus might be associated with extremes of adiposity. To address this question, we searched for rare, private or de novo copy number variation in a cohort of 985 obese and 869 lean subjects of European ancestry drawn from the extremes of the BMI distribution, genotyped on Affymetrix 6.0 arrays. A ∼680 kb duplication, confirmed by real-time PCR and G-to-FISH analyses, was observed between ∼rs11859825 and rs9932411 in a 68-year-old male with severe obesity. The duplicated region on chromosome 16 spans the entire genome-wide association studies risk locus for obesity, and further encompasses RBL2, AKTIP, RPGRIP1L and all but the last exon of the FTO gene. Affected family members exhibit a unique obesity phenotype, characterized by increased fat distribution in the shoulders and neck with a significantly increased neck circumference. This phenotype was accompanied by increased peripheral blood expression of RBL2 with no alteration in expression of FTO or other genes in the region. No other duplications or deletions in this region were identified in the cohort of obese and lean individuals or in a further survey of 4778 individuals, suggesting that large rare copy number variants surrounding the FTO gene are not a frequent cause of obesity.

Pathogenic bacteria secrete various virulence factors that can directly interact with the outer lipid bilayer membrane of eukaryotic cells, inducing cell death by apoptosis or necrosis. Such virulence factors account for much of the toxic action associated with bacterial infection; therefore the detection of such proteins could provide a methodology for sensing/detection of pathogenic bacteria in, for example, food or human tissue. Detection and identification of pathogenic bacteria by conventional methods such as plating and counting in laboratory is expensive and time consuming. With growing concerns over emergence and re-emergence of pathogenic bacteria with high resistant to current antibiotics, there is a potential need for effective detection of pathogenic toxins in-vitro. This paper presents the application of tethered bilayer lipid membrane (TBLM) as a sensing platform for the detection of the clinically relevant pathogenic bacterial, Staphylococcus aureus MSSA 476 and Pseudomonas aeruginosa PAO1 via their secreted virulence factors, using electrochemical impedance spectroscopy (EIS). A non-pathogenic strain of bacteria, E. coli DH5α was used as a control. A clear difference in the impedance of the TBLM for the pathogenic vs. non-pathogenic species was observed. Keywords: Pathogenic bacteria, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Pore-forming toxins, Electrochemical impedance spectroscopy

29 male patients (14 from Taunggyi, 6 from Rangoon and 9 from Tharrawaddy in Burma) were treated simultaneously with 200 mg artemether (Single intramuscular dose), 1500 mg sulfadoxine and 75 mg [corrected] pyrimethamine (orally). The mean parasite clearance time was 106.7 +/- 48.7 h. Side effects were few and self-limiting. 13 of 29 patients had recrudescences before day 28; as all the patients were living in towns, reinfection was unlikely. This parasite clearance time was longer than that in patients treated with artemether alone (600 mg total dose), and the recrudescence rate was higher. This drug combination is not recommended for patients in areas where sulfadoxine/pyrimethamine resistance is already established.