NONO enhances mRNA processing of super‐enhancer‐associated GATA2 and HAND2 genes in neuroblastoma

High‐risk neuroblastoma patients have poor survival rates and require better therapeutic options. High expression of a multifunctional DNA and RNA‐binding protein, NONO, in neuroblastoma is associated with poor patient outcome; however, there is little understanding of the mechanism of NONO‐dependent oncogenic gene regulatory activity in neuroblastoma. Here, we used cell imaging, biochemical and genome‐wide molecular analysis to reveal complex NONO‐dependent regulation of gene expression. NONO forms RNA‐ and DNA‐tethered condensates throughout the nucleus and undergoes phase separation in vitro, modulated by nucleic acid binding. CLIP analyses show that NONO mainly binds to the 5′ end of pre‐mRNAs and modulates pre‐mRNA processing, dependent on its RNA‐binding activity. NONO regulates super‐enhancer‐associated genes, including HAND2 and GATA2. Abrogating NONO RNA binding, or phase separation activity, results in decreased expression of HAND2 and GATA2. Thus, future development of agents that target RNA‐binding activity of NONO may have therapeutic potential in this cancer context.     

Vector competence of Coquillettidia linealis (Skuse) (Diptera: Culicidae) for Ross River and Barmah Forest viruses

Abstract Coquillettidia linealis is a severe pest on some of the Moreton Bay islands in Queensland, Australia, but little is known of its breeding habitats and biology. Because of its high abundance and its association with Ross River (RR) and Barmah Forest (BF) viruses by field isolation, its vector competence was evaluated in the laboratory by feeding dilutions of both viruses in blood. For RR, Cq. linealis was of comparable efficiency to Ochlerotatus vigilax (Skuse), recognised as being a major vector. Results were as follows for Cq. linealis and Oc. vigilax , respectively: dose to infect 50%, 10^2.2 and <10^1.7 CCID₅₀/mosquito; 88% and 90% disseminated infection at 4 days postinfection; transmission at 4 days with rates of 68−92% and 25−60%. For BF dose to infect 50%, 10^2.7 and 10^2.0; disseminated infection rates on first transmission day (day 6), 40% and 70%; transmission rates of 8−16% and 0−10%. As a capillary-tube method was used rather than suckling mice to demonstrate transmission, transmission rates may be underestimates. This, the first study of the vector competence of Cq. linealis in Australia, demonstrates that this species deserves control on the southern Moreton Bay islands.     

Isolation of Helicobacter pylori from the intestinal mucosa of patients with Crohn's disease

BACKGROUND: Helicobacter species are associated with inflammatory bowel disease in rodents and in nonhuman primates. Therefore, we prospectively investigated the presence of Helicobacter species in the intestinal mucosa of patients with and without Crohn's disease by culture and polymerase chain reaction (PCR) assays. MATERIALS AND METHODS: Mucosal fragments were obtained from the ileum, different colon regions, and rectum of 43 patients with Crohn's disease and of 74 patients without inflammatory bowel disease. RESULTS: Helicobacter pylori strains, identified by 16S rRNA gene sequencing, were more frequently isolated and PCR-detected in the intestinal mucosa of patients with ulcerative colitis-like Crohn's disease than in intestinal mucosa of the control group. Otherwise, anti-H. pylori immunoglobulin G levels were significantly lower in fibrostenosing and fistulating Crohn's disease subgroups. No other Helicobacter species were found in the intestinal mucosa of the patients. CONCLUSIONS: Although our results suggest an association between the presence of H. pylori in the intestine and ulcerative colitis-like phenotype of Crohn's disease, H. pylori infection in the actual causality of Crohn's disease is still to be determined.     

Distribution and biological role of the oligopeptide-binding protein (OppA) in Xanthomonas species

In this study we investigated the prevalence of the oppA gene, encoding the oligopeptide binding protein (OppA) of the major bacterial oligopeptide uptake system (Opp), in different species of the genus Xanthomonas. The oppA gene was detected in two Xanthomonas axonopodis strains among eight tested Xanthomonas species. The generation of an isogenic oppA-knockout derivative of the Xac 306 strain, showed that the OppA protein neither plays a relevant role in oligopeptide uptake nor contributes to the infectivity and multiplication of the bacterial strain in leaves of sweet orange (Citrus sinensis) and Rangpur lime (Citrus limonia). Taken together these results suggest that the oppA gene has a recent evolutionary history in the genus and does not contribute in the physiology or pathogenesis of X. axonopodis.     

Zinc: an inhibitor of prolactin (PRL) secretion in humans

The response of plasma prolactin (PRL) to oral administration of increasing doses of zinc (25.0, 37.5 and 50.0 mg) was studied in 17 normal adult men and women. Blood samples were collected at 10 and 30-min intervals over a period of 120 min after two basal times (-30 and 0 min). PRL concentrations significantly fell below basal levels in all subjects in response to the increase in plasma zinc levels, as compared to the controls. These results suggest that acute hyperzincemia can inhibit basal PRL secretion in normal individuals.     

Production of functionally active <Emphasis Type="Italic">Penicillium chrysogenum</Emphasis> isopenicillin N synthase in the yeast <Emphasis Type="Italic">Hansenula polymorpha</Emphasis>

Background  

β-Lactams like penicillin and cephalosporin are among the oldest known antibiotics used against bacterial infections. Industrially, penicillin is produced by the filamentous fungus Penicillium chrysogenum. Our goal is to introduce the entire penicillin biosynthesis pathway into the methylotrophic yeast Hansenula polymorpha. Yeast species have the advantage of being versatile, easy to handle and cultivate, and possess superior fermentation properties relative to filamentous fungi. One of the fundamental challenges is to produce functionally active enzyme in H. polymorpha.