Inferring exposure to harmful pseudo-nitzschia blooms from ocean-to-estuary gradients in domoic acid concentrations in Humboldt Bay bivalves

Harmful algal blooms (HABs) result from outbreaks of any of several different species of toxin-producing phytoplankton and that can have major detrimental effects on marine ecosystems and pose severe health and economic threats to human communities. Of particular concern along the United States West Coast are HABs of pennate diatom genus Pseudo-nitzschia that produce the potent neurotoxin domoic acid (DA). The coastal ocean between Cape Mendocino, CA, and Cape Blanco, OR is a hotspot for Pseudo-nitzschia spp. HABs. Such blooms impact coastal fisheries and pose a potential threat to aquaculture operations in Humboldt Bay, California’s second largest estuary and largest producer of oysters. Yet, despite evidence that tidal exchanges carry Pseudo-nitzschia spp. from the ocean into the Bay, regular assays rarely detect high uptake of domoic acid in cultured oysters and sentinel mussels in upper reaches of the Bay. This study examined the gradient to which ocean-origin DA and Pseudo-nitzschia spp. enter Humboldt Bay using naturally occurring bivalves as an integrated measure of exposure. Bivalves were collected along ocean to upper estuary transects and processed for DA concentrations in their soft tissues. These samples were augmented with water samples collected to characterize the concentrations of Pseudo-nitzschia spp. and DA in the water column and to relate to DA concentrations in bivalves. Results demonstrate that DA concentrations in bivalves decline with increased distance from the mouth of the Bay in a manner that varies over time, and that this variability is linked to the variability and intensity of DA concentrations in the environment. These results provide strong support for the hypothesis that bivalves in the upper regions of the Bay experience less exposure to ocean-origin Pseudo-nitzschia spp. HABs. This study lays the foundation for understanding the dynamics and distribution of HABs in Humboldt Bay and warrants the development of future studies to map this risk in greater detail to support hypotheses regarding mechanisms that control HAB distributions and exposure

The YY1 transcription factor is a component of ribonucleoprotein complexes in xenopus laevis oocytes and embryos.

Yin Yang 1 (YY1) is a multifunctional transcription factor that is known mainly for its ability to activate or initiate transcription of a wide assortment of genes involved in cellular growth and differentiation. Xenopus laevis oocytes and embryos were used as a model to identify and characterize a potential developmental role for YY1. Northern and Western blots of oocyte and embryonic extracts showed YY1 mRNA and protein is expressed from the earliest stages of oocyte development through to tadpole stages. Examination of the transcriptional activity of YY1 in both oocytes and embryos using reporter gene constructs containing YY1-binding elements demonstrated that YY1 does not act as a repressor or activator of transcription either in oocytes or in embryos. Sub-cellular fractionation of oocytes and Western blot analysis showed YY1 is localized almost exclusively to the cytoplasm of oocytes and in cells of early embryos. Sequence analysis of YY1 revealed that it contains an established RNA binding motif located within the zinc fingers. A series of biochemical assays were performed to address the possibility that YY1 functions as a component of mRNPs in the oocyte cytoplasm. RNA gel mobility shift analyses using in vitro synthesized histone H2A transcripts and supershifts using YY1-specific antibodies suggested that YY1 or YY1-containing complexes in cytoplasmic extracts were able to bind RNA. Chromatographic analysis of oocyte lysates showed YY1 was specifically retained on oligo (dT) cellulose columns. Treatment of the same lysates with RNase abolished binding to oligo (dT), indicating that retention is dependent on the presence of intact polyadenylated RNAs. This suggested that YY1 may be a component of messenger ribonucleoprotein particles (mRNP). Separation of oocyte lysates by size exclusion chromatography (SEC) revealed that YY1 was present in large complexes with an approximate molecular mass of 480 kDa. RNase or phosphatase treatment of oocyte extracts released YY1 from high mass complexes. Analysis of phosphatase or RNase-treated extracts for DNA binding activity showed that monomeric YY1 was able to bind DNA with high affinity. Immunoprecipitation of YY1 complexes followed by cDNA synthesis and sequencing revealed that YY1 is associated with both ribosomal and messenger RNAs in the cytoplasm of the oocyte. These results indicate a novel function for YY1 as a component of messenger ribonucleoprotein particles

Porcine adenovirus type 3 E1Blarge protein downregulates the induction of IL-8

Replication-defective (E1-E3 deleted) adenovirus vector based gene delivery results in the induction of cytokines including IL-8, which may contribute to the development of inflammatory immune responses. Like other adenoviruses, E1 + E3 deleted porcine adenovirus (PAdV) 3 induces the production of IL-8 in infected cells. In contrast, no IL-8 production could be detected in cells infected with wild-type or mutant PAdV-3s containing deletion in E1A + E3 (PAV211) or E1Bsmall + E3 (PAV212). Expression of PAdV-3 E1Blarge inhibited the NF-κB dependent transcription of luciferase from IL-8 promoter. Imunofluorescence and electrophoretic mobility shift assays suggested that constitutive expression of PAdV-3 E1Blarge inhibited the nuclear translocation of NF-κB and its subsequent binding to DNA. These results suggest that E1Blarge interacts with NF-κB to prevent transcription and down regulate proinflammatory cytokine IL-8 production

Effects of handling and short-term captivity: a multi-behaviour approach using red sea urchins, Mesocentrotus franciscanus

Understanding the effects of captivity-induced stress on wild-caught animals after their release back into the wild is critical for the long-term success of relocation and reintroduction programs. To date, most of the research on captivity stress has focused on vertebrates, with far less attention paid to invertebrates. Here, we examine the effect of short-term captivity (i.e., up to four days) on self-righting, aggregation, and predator-escape behaviours in wild-caught red sea urchins, Mesocentrotus franciscanus, after their release back into the wild. Aggregation behaviour, which has been linked to feeding in sea urchins, was not affected by handling or captivity. In contrast, the sea urchins that had been handled and released immediately, as well as those that were handled and held captive, took longer to right themselves and were poorer at fleeing from predators than wild, unhandled sea urchins. These results indicate that handling rather than captivity impaired these behaviours in the short term. The duration of captivity did not influence the sea urchin behaviours examined. Longer-term monitoring is needed to establish what the fitness consequences of these short-term behavioural changes might be. Our study nevertheless highlights the importance of considering a suite of responses when examining the effects of capture and captivity. Our findings, which are based on a locally abundant species, can inform translocation efforts aimed at bolstering populations of ecologically similar but depleted invertebrate species to retain or restore important ecosystem functions

Total RNA isolated at 6 h post infection of HeLa cells with indicated viruses was analyzed by RNA protection assay using RiboQuant Multi-Probe template set hCK-5

<p><b>Copyright information:</b></p><p>Taken from "Porcine adenovirus type 3 E1Bprotein downregulates the induction of IL-8"</p><p>http://www.virologyj.com/content/4/1/60</p><p>Virology Journal 2007;4():60-60.</p><p>Published online 12 Jun 2007</p><p>PMCID:PMC1906745.</p><p></p> The protected band indicated by the label on the right migrate faster that undigested probes, as expected.HeLa cells transfected with the human IL-8 promoter containing a NF-κB recognition sequence, cloned upstream from a luciferase reporter cDNA in the presence of plasmid pCDNA3.1 or pCDNA3.1-pE1BL were assayed for luciferase activity (expressed as relative light units [RLU]). The error bars represent the standard error of mean of triplicate samples

Porcine adenovirus type 3 E1Bprotein downregulates the induction of IL-8-2

<p><b>Copyright information:</b></p><p>Taken from "Porcine adenovirus type 3 E1Bprotein downregulates the induction of IL-8"</p><p>http://www.virologyj.com/content/4/1/60</p><p>Virology Journal 2007;4():60-60.</p><p>Published online 12 Jun 2007</p><p>PMCID:PMC1906745.</p><p></p>d with radiolabeled oligonucleotide probe(s) containing wild-type (I, II) or mutant (III) NF-κB motif from human IL-8 promoter [30] with (II) or without (I) immunoprecipitation with anti- NF-κB p65 serum. Nuclear extracts from mock infected or virus infected cells containing wild-type (I) or mutant (II) NF-κB motif from human IL-8 promoter. Schematic diagram showing deletion of the regions in PAV211, PAV212 and PAV227 [19,20]

Porcine adenovirus type 3 E1Bprotein downregulates the induction of IL-8-1

<p><b>Copyright information:</b></p><p>Taken from "Porcine adenovirus type 3 E1Bprotein downregulates the induction of IL-8"</p><p>http://www.virologyj.com/content/4/1/60</p><p>Virology Journal 2007;4():60-60.</p><p>Published online 12 Jun 2007</p><p>PMCID:PMC1906745.</p><p></p>AdV-3 E1Bwere treated with TNF-α. After 15 min, the cells were fixed with 100% methanol and analyzed by indirect immunostaining with anti- NF-κB p65 antibody followed by Cy™ conjugated goat anti-mouse secondary antibody. Finally, the cells were incubated with DAPI and visualized using Zeiss AxioVision microscope. VIDO R1 cells, VR1BL cells. DAPI (blue); NF-κB p65 (red)