Pharmacological and immunological identification of native alpha7 nicotinic receptors: evidence for homomeric and heteromeric alpha7 receptors

Controversy surrounds the expression of alpha7 nicotinic acetylcholine receptors (nAChRs) in adrenal chromaffin cells. In these studies, alpha7 nAChRs expressed in bovine adrenal chromaffin cells are investigated. Using radiolabeled ligand binding techniques, [(125)I]alpha-bungarotoxin (alphaBGT) binding reaches equilibrium within 4 h and is saturable with a K(d) value of 4.2 nM. Using homologous competition experiments, the K(i) for binding of alphaBGT was 1.9 nM. These data are consistent with the expression of homomeric alpha7 nAChRs. Methyllycaconatine (MLA), which binds alpha7 nAChRs with high affinity, inhibits [(125)I]alphaBGT binding in a concentration-dependent manner with a K(i) of 30.6 nM; this value is approximately 10 fold higher than the reported affinity of MLA for alpha7 nAChRs. We also document the ability of bromoacetylcholine (brACh) to alkylate alpha7 nAChRs, as has been previous demonstrated for bovine adrenal alpha3beta4 nAChRs. When adrenal nAChRs are immunoprecipated with mAb319, an antibody which recognizes alpha7 nAChR protein, and then probed with mAb319 using Western blot analysis, a single band of approximately 53 kDa is identified. When adrenal nAChRs are immunoprecipated with mAb35, an antibody which recognizes alpha3 and alpha5 nAChR proteins, and then probed with mAb319 using Western blot analysis, a single band of approximately 53 kDa is identified. Together, these results support the expression of alpha7 nAChRs in bovine adrenal chromaffin cells. However, these data suggest that the subunit composition of some of these receptors may include heteromeric alpha7 nAChRs.     

A Compact,High-Accuracy Cas9 with a Dinucleotide PAM for In Vivo Genome Editing

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Effects of different forms of olive cake on the performance and carcass quality of Awassi lambs

Effects of form of olive cake (OC) on growth performances and carcass quality were studied on forty-eight Awassi lambs. All lambs were male with an average body weight of 29.5 kg (S.D. = 2.3 kg) at the beginning of the experiment. Animals were randomly divided into four groups of 12 lambs each. Lambs in each group received individually corn–soybean meal (SBM) total mixed rations (TMRs). Rations were incorporated with a fixed amount (149 g/kg DM) of OC of different forms: crude OC, a product of the three centrifugation extraction procedure (control group), alkali treated, ensiled and pelleted. All rations were isonitrogenous and isocaloric. The growth experiment lasted 10 weeks. In the following week, all lambs were slaughtered. At termination of the experiment, lambs fed crude, alkali treated or ensiled OC rations consumed more feed and gained more weight (P<0.05) than those fed the pelleted OC. This same trend was found for the feed conversion (FC), carcass and empty body weights (EBWs). However, external (hide, head and feet, HHF) and thoracic organs (heart and lungs, HL), gut and liver weights proportional to EBW (g/kg) were not affected by the form of OC. The form of OC had no effects on muscle (P=0.4) and bone (P=0.21) tissues. Carcass, pelvic, kidney fats and total carcass fats weights when expressed as g/kg EBW and the percent of carcass fat of total body fat (TBF) were lower in lambs fed the pelleted OC compared to those offered the other forms of OC. However, the subcutaneous, inter muscular and TBF fats weights (g/kg) were comparable among lambs in different OC form rations. Results from this work suggest that the treated OC had no advantages compared to crude in regard to parameters investigated in this research.     

11-Phenyl-[b,e]-dibenzazepine compounds: Novel antitumor agents

A series of 11-phenyl-[b,e]-dibenzazepine compounds were synthesized and shown to be inhibitors of tumor cell proliferation with IC₅₀ values ranging from submicromolar to micromolar concentrations. Flow cytometric analyses of several active compounds demonstrated inhibition of cell cycle progression at the G₀–G₁ phase transition resulting in G₀–G₁ arrest.     

Potent antimicrobial activity of 3-(4,5-diaryl-1H-imidazol-2-yl)-1H-indole derivatives against methicillin-resistant Staphylococcus aureus

A new series of antimicrobial derivatives [3-(4,5-diaryl-1H-imidazol-2-yl)-1H-indole)] have been synthesized with potent activity against strains of Staphylococcus aureus, including methicillin-resistant strains (MRSA). Compound 17 [3-(4,5-bis(4-fluorophenyl)-1H-imidazol-2-yl)-5-bromo-1H-indole], the most active derivative was shown to inhibit the growth of all Gram-positive strains tested, including vancomycin resistant Enterococcus faecalis and Enterococcus faecium with no activity against Gram-negative bacteria.     

Securing Mobile Ad Hoc Networks Using Danger Theory-Based Artificial Immune Algorithm

A mobile ad hoc network (MANET) is a set of mobile, decentralized, and self-organizing nodes that are used in special cases, such as in the military. MANET properties render the environment of this network vulnerable to different types of attacks, including black hole, wormhole and flooding-based attacks. Flooding-based attacks are one of the most dangerous attacks that aim to consume all network resources and thus paralyze the functionality of the whole network. Therefore, the objective of this paper is to investigate the capability of a danger theory-based artificial immune algorithm called the mobile dendritic cell algorithm (MDCA) to detect flooding-based attacks in MANETs. The MDCA applies the dendritic cell algorithm (DCA) to secure the MANET with additional improvements. The MDCA is tested and validated using Qualnet v7.1 simulation tool. This work also introduces a new simulation module for a flooding attack called the resource consumption attack (RCA) using Qualnet v7.1. The results highlight the high efficiency of the MDCA in detecting RCAs in MANETs.     

Functional regulation of MyD88-activated interferon regulatory factor 5 by K63-linked polyubiquitination

Interferon regulatory factor 5 (IRF-5) plays an important role in the innate antiviral and inflammatory response. Specific IRF-5 haplotypes are associated with dysregulated expression of type I interferons and predisposition to autoimmune disorders. IRF-5 is activated by Toll-like receptor 7 (TLR7) and TLR9 via the MyD88 pathway, where it interacts with both MyD88 and the E3 ubiquitin ligase, TRAF6. To understand the role of these interactions in the regulation of IRF-5, we examined the role of ubiquitination and showed that IRF-5 is subjected to TRAF6-mediated K63-linked ubiquitination, which is important for IRF-5 nuclear translocation and target gene regulation. We show that while the murine IRF-5 and human IRF-5 variant 4 (HuIRF-5v4) and HuIRF-5v5 are ubiquitinated, an IRF-5 bone marrow variant mutant containing an internal deletion of 288 nucleotides is not ubiquitinated. Lysine residues at positions 410 and 411 in a putative TRAF6 consensus binding domain of IRF-5 are the targets of K63-linked ubiquitination. Mutagenesis of these two lysines abolished IRF-5 ubiquitination, nuclear translocation, and the IFNA promoter-inducing activity but not the IRF-5-TRAF6 interaction. Finally, we show that IRAK1 associates with IRF-5 and that this interaction precedes and is required for IRF-5 ubiquitination and activation. Thus, our findings offer a new mechanistic insight into IRF-5 gene induction program through hitherto unknown processes of IRF-5 ubiquitination.     

O-fucosylation of thrombospondin type 1 repeats in ADAMTS-like-1/punctin-1 regulates secretion: implications for the ADAMTS superfamily

The ADAMTS superfamily contains several metalloproteases (ADAMTS proteases) as well as ADAMTS-like molecules that lack proteolytic activity. Their common feature is the presence of one or more thrombospondin type-1 repeats (TSRs) within a characteristic modular organization. ADAMTS like-1/punctin-1 has four TSRs. Previously, O-fucosylation on Ser or Thr mediated by the endoplasmic reticulum-localized enzyme protein-O-fucosyltransferase 2 (POFUT2) was described for TSRs of thrombospondin-1, properdin, and F-spondin within the sequence Cys-Xaa(1)-Xaa(2)-(Ser/Thr)-Cys-Xaa-Xaa-Gly (where the fucosylated residue is underlined). On mass spectrometric analysis of tryptic peptides from recombinant secreted human punctin-1, the appropriate peptides from TSR2, TSR3, and TSR4 were found to bear either a fucose monosaccharide (TSR3, TSR4) or a fucose-glucose disaccharide (TSR2, TSR3, TSR4). Although mass spectral analysis did not unambiguously identify the relevant peptide from TSR1, metabolic labeling of cells expressing TSR1 and the cysteine-rich module led to incorporation of [(3)H]fucose into this construct. Mutation of the putative modified Ser/Thr residues in TSR2, TSR3, and TSR4 led to significantly decreased levels of secreted punctin-1. Similarly, expression of punctin-1 in Lec-13 cells that are deficient in conversion of GDP-mannose to GDP-fucose substantially decreased the levels of secreted protein, which were restored upon culture in the presence of exogenous l-fucose. In addition, mutation of the single N-linked oligosaccharide in punctin-1 led to decreased levels of secreted punctin-1. Taken together, the data define a critical role for N-glycosylation and O-fucosylation in the biosynthesis of punctin-1. From a broad perspective, these data suggest that O-fucosylation may be a widespread post-translational modification in members of the ADAMTS superfamily with possible regulatory consequences.     

The establishment of two parasites of the diamond-back mothPlutella xylostella [Lep.: Plutellidae] in Trinidad,W.I.

The diamond-back moth,Plutella xylostella (L.) is a major pest of cruciferous crops in Trinidad, West Indies. Pesticides are applied as a control measure but it is now resistant to several of them. Indigenous parasitesApanteles aciculatus (Ashm.),Apanteles sp. (glomeratus group),Spilochalcis hirtifemora (Ashm.) andTrichogramma brasiliensis (Ashm.) are unable to exert economic control.Apanteles plutellae (Kurdj.) andTetrastichus sokolowskii Kurdj. were introduced and are now well established. It is recommended to introduce additional parasitesMacromalon sp. andThyraeella collaris (Grav.) in order to obtain complete biological control.