HnRNP L and HnRNP A1 Induce Extended U1 snRNA Interactions with an Exon to Repress Spliceosome Assembly

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Highlights? HnRNP L recruits hnRNP A1 and U1 snRNA to sequences upstream of the 5′ splice site ? HnRNP L-induced extended base pairing of U1 snRNA inhibits exchange for U6 snRNA ? Local traps in spliceosome assembly are naturally exploited mechanisms of regulation ? Extended base pairing of U1 may account for much of regulation by hnRNPs L and A1     

A potential field suppression system for Bactrocera dorsalis Hendel

Development of an effective and safe detection or control system is important for pest management. Attractants for male fruit flies, e.g., methyl eugenol (ME), are currently being used in fruit fly control in combination with insecticides. A single formulation that possesses both attraction and killing properties would improve control methods and cost effectiveness. We previously observed the attraction of oriental fruit flies to a basil plant in a yard and confirmed the attraction of male fruit flies to basil oil (BO) in the laboratory. Subsequently, we identified insecticidal compounds from BO that killed three species of tephritid fruit flies in the laboratory, and we also discovered physiological interactions between BO constituents and male attractants. Based on these observations, we developed a single package of basil oil and methyl eugenol (BO + ME) formulation that possesses “attract and kill” properties in combination with a modified AWPM standard trap for field application. The effectiveness of this system is dependent on the type of trap and weather conditions (sunny or not sunny). Any attracted flies were killed within 2 h after entering the BO + ME trap. The combination of BO, ME, and a clear bucket trap may be a novel alternative for a cost effective and environmentally friendly fruit fly management system.     

Efficacy of heat-labile enterotoxin B subunit-adjuvanted parenteral porcine epidemic diarrhea virus trimeric spike subunit vaccine in piglets

Applied Microbiology and Biotechnology - Devastating outbreaks of porcine epidemic diarrhea (PED) started in China in late 2010 and rapidly spread to North America and Asia causing severe diarrhea...     

Oxidant-Induced Activation of Protein Kinase C in Uc11mg Cells

Free radical formation and subsequent lipid peroxidation may participate in the pathogenesis of tissue injury, including the brain injury induced by hypoxia or trauma and cardiac injury arising from ischemia and reperfusion. However, the exact cellular mechanisms by which the initial oxidative insult leads to the ultimate tissue damage are not known. A number of reports have indicated that protein kinase C (PKC) may be activated following oxidative stress and that this enzyme may play an important role in the steps leading to cellular damage. In this work, we have examined in a cell model whether PKC is activated following oxidative exposure. UC11MG cells, a human astrocytoma cell line, were treated with H₂O₂. Incubation with 0.5 mM H₂O₂ increased malondialdehyde levels by as early as 15 minutes. To assess the effects of H₂O₂ treatment on PKC activation, we measured phosphorylation of an endogenous PKC substrate, the MARCKS (myristoylated alanine-rich C kinase substrate) protein. Treatment of cells with 0.2-1.0 mM H₂O₂ resulted in a rapid increase in MARCKS phosphorylation. Phosphorylation was stimulated approximately 2.5-fold following treatment with 0.5 mM H₂O₂ for ten minutes. Treatment with phorbol 12-myristate 13-acetate, a PKC activator, increased MARCKS phosphorylation approximately 4-fold. The H₂O₂-induced MARCKS phosphorylation was inhibited by the addition of the kinase inhibitors H-7 and staurosporine. Furthermore, specific down-regulation of PKC by phorbol ester also inhibited H₂O₂-induced MARCKS phosphorylation. These results indicate that PKC is rapidly activated in cells following an oxidative exposure and that this cell system may be a good model to further investigate the role of PKC in regulating oxidative damage in the cell.     

Purification and characterization of a novel phospholipase A2 from king cobra (Ophiophagus hannah) venom

A novel phospholipase A₂, designated as Oh-DE-2, was isolated from the venom ofOphiophagus hannah (king cobra) by successive chromatography on SP-Sephadex C-25, DE-52, and Q-Sepharose columns. Oh-DE-2 with pI 5.1 showed an apparent molecular weight of 14 kD as revealed by SDS-PAGE and gel filtration. The amino acid sequence was homologous with those of PLA₂s from Elapidae venoms. Oh-DE-2 was effectively inactivated byp-bromophenacyl bromide, indicating that the conserved His-48 is essential for its enzymatic activity. However, modification of the conserved Trp-19 did not cause a precipitous drop in the enzymatic activity of Oh-DE-2 as observed with PLA₂s fromNaja naja atra andBungarus multicinctus venoms. A quenching study showed that the microenvironment of Trp in Oh-DE-2 was inaccessible to acrylamide, iodide, or cesium, a finding which was different from those observed with PLA₂s fromN. naja atra andB. multicinctus venoms. These results might suggest that, unlike other PLA₂ enzymes, Trp-19 in Oh-DE-2 is not directly involved in its enzymatic mechanisms.     

Estimation of Fungal Infection of Peanut Kernels by Determination of Free Glutamic Acid Content

Peanut kernels (Tainan 9, a Spanish cultivar) inoculated with Aspergillus parasiticus, A. flavus, A. niger, or A. ochraceus as well as noninoculated kernels were incubated in a humidified environment (relative humidity, 100%) at 25(deg)C for 7 weeks. Internal fungal populations and changes in moisture and sucrose content and free amino acid composition of the kernels were determined periodically. Fungal populations determined by using A. flavus and A. parasiticus agar and rose bengal chlortetracycline agar as enumerating media were closely correlated. Moisture content in the kernels increased from 5.8 to 20.4% (dry basis), and changes in individual free amino acid contents varied, depending upon the incubation time and type of fungus used as an inoculum. In the early infection period (up to 5 weeks), sucrose contents and logarithms of threonine and tyrosine contents increased while logarithms of free glutamic acid content decreased linearly with incubation time. A negative linear relationship was further obtained between logarithms of fungal populations and the logarithm of free glutamic acid content (R(sup2) > 0.80) of the infected peanut kernels.     

Morphological characterization of infra‐generic lineages in Deparia (Athyriaceae: Polypodiales)

Deparia, including the previously recognized genera Lunathyrium, Dryoathyrium (=Parathyrium), Athyriopsis, Triblemma, and Dictyodroma, is a fern genus comprising about 70 species in Athyriaceae. In this study, we inferred a robust Deparia phylogeny based on a comprehensive taxon sampling (~81% of species) that captures the morphological diversity displayed in the genus. All Deparia species formed a highly supported monophyletic group. Within Deparia, seven major clades were identified, and most of them were characterized by inferring synapomorphies using 14 morphological characters including leaf architecture, petiole base, rhizome type, soral characters, spore perine, and leaf indument. These results provided the morphological basis for an infra‐generic taxonomic revision of Deparia.     

Antioxidant and oxidative status in tissues of manganese superoxide dismutase transgenic mice

Manganese superoxide dismutase (Mn-SOD) plays an important role in attenuating free radical-induced oxidative damage. The purpose of this research was to determine if increased expression of Mn-SOD gene alters intracellular redox status. Twelve week old male B6C3 mice, engineered to express human Mn-SOD in multiple organs, and their nontransgenic littermates were assessed for oxidative stress and antioxidant status in heart, brain, lung, skeletal muscle, liver, and kidney. Relative to their nontransgenic littermates, transgenic mice had significantly (p <.01) higher activity of Mn-SOD in heart, skeletal muscle, lung, and brain. Copper, zinc (Cu,Zn)-SOD activity was significantly higher in kidney, whereas catalase activity was lower in brain and liver. The activities of selenium (Se)-GSH peroxidase and non-Se-GSH peroxidase, and levels of vitamin E, ascorbic acid and GSH were not significantly different in any tissues measured between Mn-SOD transgenic mice and their nontransgenic controls. The levels of malondialdehyde were significantly lower in the muscle and heart of Mn-SOD mice, and conjugated dienes and protein carbonyls were not altered in any tissues measured. The results obtained showed that expression of human SOD gene did not systematical alter antioxidant systems or adversely affect the redox state of the transgenic mice. The results also suggest that expression of human SOD gene confers protection against peroxidative damage to membrane lipids.