Ribosomal protein S14 is not responsible for the Minute phenotype associated with the M(1)7C locus in Drosophila melanogaster.

Summary A locus associated with a severe Minute effect has been mapped at 7C on the X chromosome of Drosophila melanogaster. Previous work has suggested that this Minute encodes ribosomal proteins S14A and S141B. We have made a chromosomal deficiency that removes the S14 ribosomal protein genes, yet does not display the Minute phenotype. These data suggest that the S14 genes do not actually correspond to the Minute locus.     

A region immediately adjacent to the origin of replication of bovine papilloma virus type 1 interacts in vitro with the nuclear matrix.

We have investigated the interaction of the 69% transforming fragment of the Bovine Papilloma Virus type 1 (BPV1) with the nuclear matrix from 1361.5 cells (NIH-3T3 cells transformed by a BPV chimeric construct). In vitro studies performed with end-labelled DNA fragments and nuclear matrices prepared using a high-salt extraction procedure demonstrate the binding of a 672 bp fragment adjacent to the viral origin of replication and containing the plasmid maintenance sequence (PMS-1). This fragment can be cleaved into two pieces (393 and 279 bp), both interacting equally well with the nuclear matrix. This indicates that a least two regions of the 672 bp DNA fragment are involved in the interaction.     

Dose/dose-rate responses of shrimp larvae to UV-B radiation

Summary Previous work indicated dose-rate thresholds in the effects of UV-B on the near-surface larvae of three shrimp species. Additional observations suggest that the total dose response varies with dose-rate. Below 0.002 Wm^-2 _[DNA] irradiance no significant effect is noted in activity, development, or survival. Beyond that dose-rate threshold, shrimp larvae are significantly affected if the total dose exceeds about 85 Jm^-2 _[DNA]. Predictions cannot be made without both the dose-rate and the dose.These dose/dose-rate thresholds are compared to four-year mean dose/dose-rate solar UV-B irradiances at the experimental site, measured at the surface and calculated for 1 m depth. The probability that the shrimp larvae would receive lethal irradiance is low for the first half of the season of surface occurrence, even with a 44% increase in damaging UV radiation.Contribution No. 1183 from the Department of Oceanography, University of Washington, Seattle, WA 98195, USA     

The effect of interferon on lymphocyte-mediated effector cell functions: selective enhancement of natural killer cells.

The effect of human interferons on different types of lymphocyte-mediated killer assays was explored. Killing by T cells generated through mixed lymphocyte cultures as well as antibody-dependent lymphocyte-mediated cytotoxicity was not influenced by the addition of interferon. Enhancement of cytolysis produced by natural killer cells was observed when interferon was added during the assay, but enhancement could also be induced if the effector cells were pretreated with interferon for 2 hr prior to the lytic reaction. Killing of a cell line susceptible to natural killing was increased and a cell line which is normally relatively resistant to this type of killing became a susceptible target.     

Regulatory effect of interferon on T cells in vitro.

Purified human lymphocyte interferon (PIF) was added to mixed lymphocyte cultures; DNA synthesis was measured and killer-cell generation was determined. At certain concentrations, PIF ingibited proliferation, but at the same time increased the killer efficiency of the resultant culture cells. It is suggested that lymphokines, apart from their normal mediator function, may play a role as regulators of the generating immune response.     

Quantifying Climatological Ranges and Anomalies for Pacific Coral Reef Ecosystems

Coral reef ecosystems are exposed to a range of environmental forcings that vary on daily to decadal time scales and across spatial scales spanning from reefs to archipelagos. Environmental variability is a major determinant of reef ecosystem structure and function, including coral reef extent and growth rates, and the abundance, diversity, and morphology of reef organisms. Proper characterization of environmental forcings on coral reef ecosystems is critical if we are to understand the dynamics and implications of abiotic–biotic interactions on reef ecosystems. This study combines high-resolution bathymetric information with remotely sensed sea surface temperature, chlorophyll-a and irradiance data, and modeled wave data to quantify environmental forcings on coral reefs. We present a methodological approach to develop spatially constrained, island- and atoll-scale metrics that quantify climatological range limits and anomalous environmental forcings across U.S. Pacific coral reef ecosystems. Our results indicate considerable spatial heterogeneity in climatological ranges and anomalies across 41 islands and atolls, with emergent spatial patterns specific to each environmental forcing. For example, wave energy was greatest at northern latitudes and generally decreased with latitude. In contrast, chlorophyll-a was greatest at reef ecosystems proximate to the equator and northern-most locations, showing little synchrony with latitude. In addition, we find that the reef ecosystems with the highest chlorophyll-a concentrations; Jarvis, Howland, Baker, Palmyra and Kingman are each uninhabited and are characterized by high hard coral cover and large numbers of predatory fishes. Finally, we find that scaling environmental data to the spatial footprint of individual islands and atolls is more likely to capture local environmental forcings, as chlorophyll-a concentrations decreased at relatively short distances (>7 km) from 85% of our study locations. These metrics will help identify reef ecosystems most exposed to environmental stress as well as systems that may be more resistant or resilient to future climate change.     

Expression of mRNA Encoding Mcu and Other Mitochondrial Calcium Regulatory Genes Depends on Cell Type,Neuronal Subtype,and Ca2+ Signaling

Uptake of Ca²⁺ into the mitochondrial matrix controls cellular metabolism and survival-death pathways. Several genes are implicated in controlling mitochondrial Ca²⁺ uptake (mitochondrial calcium regulatory genes, MCRGs), however, less is known about the factors which influence their expression level. Here we have compared MCRG mRNA expression, in neural cells of differing type (cortical neurons vs. astrocytes), differing neuronal subtype (CA3 vs. CA1 hippocampus) and in response to Ca²⁺ influx, using a combination of qPCR and RNA-seq analysis. Of note, we find that the Mcu-regulating Micu gene family profile differs substantially between neurons and astrocytes, while expression of Mcu itself is markedly different between CA3 and CA1 regions in the adult hippocampus. Moreover, dynamic control of MCRG mRNA expression in response to membrane depolarization-induced Ca²⁺ influx is also apparent, resulting in repression of Letm1, as well as Mcu. Thus, the mRNA expression profile of MCRGs is not fixed, which may cause differences in the coupling between cytoplasmic and mitochondrial Ca²⁺, as well as diversity of mitochondrial Ca²⁺ uptake mechanisms.     

Eight decades of invasion by Chromolaena odorata (Asteraceae) and its biological control in West Africa: the story so far

ABSTRACT

Chromolaena odorata (L.) R.M. King and H. Robinson (Asteraceae) is a perennial weedy shrub of neotropical origin and a serious biotic threat in its invasive range. The Asian-West Africa (AWA) biotype of C. odorata present in West Africa is both morphologically and genetically different from the southern African (SA) biotype. The AWA biotype was first introduced into Nigeria in the late 1930s and rapidly spread across West Africa. Currently, 12 of the 16 countries in West Africa have been invaded, with significant negative effects on indigenous flora and fauna. However, locals in West Africa have found several uses for the weed. As chemical, physical and other conventional methods were unsustainable, costly and largely ineffective, three biological control agents, Apion brunneonigrum (Coleoptera: Brentidae), Pareuchaetes pseudoinsulata (Lepidoptera: Erebidae) and Cecidochares connexa (Diptera: Tephritidae), have been released in West Africa between the 1970s and the early 2000s. However, only C. connexa and P. pseudoinsulata established, contributing to the control of the weed, in six and four countries in West Africa respectively. Limited research funding, the absence of post-release evaluations of the established agents, and the ‘conflict of interest’ status of C. odorata (i.e. being beneficial for local use but damaging to ecosystem services and agriculture), are serious factors deterring the overall biological control effort. Here, using historical records and field surveys, we examine the invasion history, spread, impacts, and management of C. odorata in West Africa and make recommendations for the sustainable management of C. odorata in the region.     

4-Deoxyraputindole C induces cell death and cell cycle arrest in tumor cell lines

Several molecules extracted from natural products exhibit different biological activities, such as ion channel modulation, activation of signaling pathways, and anti-inflammatory or antitumor activity. In this study, we tested the antitumor ability of natural compounds extracted from the Raputia praetermissa plant. Among the compounds tested, an alkaloid, here called compound S4 (4-Deoxyraputindole C), showed antitumor effects against human tumor lineages. Compound S4 was the most active against Raji, a lymphoma lineage, promoting cell death with characteristics that including membrane permeabilization, dissipation of the mitochondrial potential, increased superoxide production, and lysosomal membrane permeabilization. The use of cell death inhibitors such as Z-VAD-FMK (caspase inhibitor), necrostatin-1 (receptor-interacting serine/threonine-protein kinase 1 inhibitor), E-64 (cysteine peptidases inhibitor), and N-acetyl- L -cysteine (antioxidant) did not decrease compound S4-dependent cell death. Additionally, we tested the effect of cellular activity on adherent human tumor cells. The highest reduction of cellular activity was observed in A549 cells, a lung carcinoma lineage. In this lineage, the effect on the reduction of the cellular activity was due to cell cycle arrest, without plasma membrane permeabilization, loss of the mitochondrial potential or lysosomal membrane permeabilization. Compound S4 was able to inhibit cathepsin B and L by a nonlinear competitive (negative co-operativity) and simple-linear competitive inhibitions, respectively. The potency of inhibition was higher against cathepsin L. Compound S4 promoted cell cycle arrest at G ₀ and G ₂ phase, and increase the expression of p16 and p21 proteins. In conclusion, compound S4 is an interesting molecule against cancer, promoting cell death in the human lymphoma lineage Raji and cell cycle arrest in the human lung carcinoma lineage A549.     

Mutual interactions between DTaP-IPV and Haemophilus influenzae type b (Hib)-conjugated vaccines in laboratory animal models.

Potency and/or immunogenicity of three different Haemophilus influenzae type b-conjugated vaccines (Hib) and a DTaP-IPV vaccine alone, and their mutual interactions in DTaP-IPV-Hib combination was tested. In a mouse model, only combination of Act-Hib, in which tetanus toxoid (TT) was as active as non-conjugated TT, significantly increased the immunogenicity and potency of TT component of DTaP-IPV vaccine. Also, only combination of Hib-TITER, in which CRM197 was used as the carrier with DTaP-IPV, increased the potency of diphtheria toxoid (DT) component of DTaP-IPV vaccine significantly. It shows that the additive effect of tested Hib vaccines on immunogenicity and/or potency of TT and DT was mostly due to the existence of TT and CRM197, respectively, as the carrier in the mentioned Hib vaccines. No difference was shown in inoculation of DTaP-IPV and Hib conjugated vaccines in the same syringe or at separate sites. DTaP-IPV had dual effects on anti-Hib capsular polysaccharide (HibCP) responses to Hib vaccines in the mouse model. This duality was probably related to the carrier B-cell epitopes activity of Hib conjugated vaccines. The immunogenicity of TT component of Act-Hib and Amvax Hib-TT in the guinea pig model was shown and combination of mentioned Hib vaccines with DTaP-IPV, remarkably increased anti-TT antibody responses to the TT component of DTaP-IPV vaccine. These confirmed our results in the mouse model. Using two different protocols to evaluate the guinea pig model for induction of anti-HibCP immunity showed that a "long interval" protocol does not have any advantage over the "short interval" protocol. Also, combination of DTaP-IPV with Hib vaccines did not have any noticeable effect on anti-HibCP antibodies in the guinea pig model. Taken together, our observations in laboratory animal models may facilitate a better understanding of the mutual interactions between the different antigen components of a combined vaccine such as DTaP-IPV-Hib vaccine.