Nutritional status modulates box C/D snoRNP biogenesis by regulated subcellular relocalization of the R2TP complex

BACKGROUND: Box C/D snoRNPs, which are typically composed of box C/D snoRNA and the four core protein components Nop1, Nop56, Nop58, and Snu13, play an essential role in the modification and processing of pre-ribosomal RNA. The highly conserved R2TP complex, comprising the proteins Rvb1, Rvb2, Tah1, and Pih1, has been shown to be required for box C/D snoRNP biogenesis and assembly; however, the molecular basis of R2TP chaperone-like activity is not yet known. RESULTS: Here, we describe an unexpected finding in which the activity of the R2TP complex is required for Nop58 protein stability and is controlled by the dynamic subcellular redistribution of the complex in response to growth conditions and nutrient availability. In growing cells, the complex localizes to the nucleus and interacts with box C/D snoRNPs. This interaction is significantly reduced in poorly growing cells as R2TP predominantly relocalizes to the cytoplasm. The R2TP-snoRNP interaction is mainly mediated by Pih1. CONCLUSIONS: The R2TP complex exerts a novel regulation on box C/D snoRNP biogenesis that affects their assembly and consequently pre-rRNA maturation in response to different growth conditions. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13059-014-0404-4) contains supplementary material, which is available to authorized users

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Inhibition of fibrogenic TNF(alpha) gene expression in pulmonary macrophages by antisense oligonucleotides.

In this study, we investigated the possibility of using antisense oligonucleotides directed against TNF{dollar}\\alpha{dollar} mRNA to specifically inhibit TNF{dollar}\\alpha{dollar} production in silica-exposed rats and to test whether this inhibition can provide any protection against silicosis. To optimize the length and sequence of antisense oligonucleotides against TNF{dollar}\\alpha{dollar} mRNA, the effect of oligonucleotide length and different target sites on TNF{dollar}\\alpha{dollar} mRNA on the antisense inhibitory activity of TNF{dollar}\\alpha{dollar} production was investigated. The antisense oligonucleotides targeted to the cap site, the initial codon and the coding region of TNF{dollar}\\alpha{dollar} mRNA was found equally effectively. The activity of antisense oligonucleotides against TNF{dollar}\\alpha{dollar} mRNA increased as the length of the oligonucleotides increased. To ensure that the inhibitory effect on TNF{dollar}\\alpha{dollar} production was an antisense effect, inverted and sense sequences were included as controls in antisense inhibition study. Neither sequence had any significant inhibition effect on TNF{dollar}\\alpha{dollar} production. TNF{dollar}\\alpha{dollar} mRNA level was also examined by RT-PCR to further confirm the antisense effect. Our results showed a significant reduction of mRNA level in cells treated with antisense oligonucleotides. In contrast, the inverted and sense sequences had no effect. A macrophage-specific carrier (MPL) which exploited endocytosis via the macrophage mannose receptor was developed in this study. We showed that MPL can significantly enhance the cellular uptake of oligonucleotides by macrophages. The mechanism of enhanced cellular uptake was through mannose-receptor mediated endocytosis. In vitro, the MPL was demonstrated to be capable of promoting the antisense inhibitory activity of oligonucleotides against macrophage production of TNF{dollar}\\alpha.{dollar} In vivo, we showed that antisense oligonucleotides can inhibit TNF{dollar}\\alpha{dollar} secretion and had a partial protection effect on lung inflammation and fibrosis, as demonstrated by our data on lung cell recruitment, lung weight, hydroxyproline content and histological examination. However, we failed to demonstrate the advantage of ON:MPL complex over free oligonucleotide. Nevertheless, these results support the hypothesis that antisense oligonucleotides can specifically inhibit TNF{dollar}\\alpha{dollar} production and this inhibition can slow down fibrosis development. However, further improvements in the drug delivery systems or administration methods, i.e., aerosolization instead of intratracheal instillation which was used in this study, may be required to fully take advantage of the promising antisense approach

Genome editing and human rights: Implications of the UNGPs

How to address the impact of genome editing on human rights is a global challenge. The World Health Organization (WHO) recently developed a governance framework for human genome editing to provide global recommendations for establishing appropriate governance mechanisms for human genome editing. This article suggests that a human rights-respecting approach should be explicitly recognized in the framework and other relevant endeavors. Such recognition has significant implications not only on clarifying the duty of States but also on the responsibility of non-State actors, particularly biotech enterprises, to orient this technology towards respect for human rights. To implement this approach, the United Nations Guiding Principles on Business and Human Rights (UNGPs) provide helpful guidance for States, biotech enterprises, and other stakeholders to raise awareness and enhance responsible practices in the field

Characteristics and factors influencing the natural regeneration of Larix principis-rupprechtii seedlings in northern China

Larix principis-rupprechtii is an important and widely distributed species in the mountains of northern China. However, it has inefficient natural regeneration in many stands and difficulty recruiting seedlings and saplings. In this study, we selected six plots with improved naturally-regenerated L. principis-rupprechtii seedlings. A point pattern analysis (pair-correlation function) was applied to identify the spatial distribution pattern and correlation between adult trees and regenerated seedlings mapped through X/Y coordinates. Several possible influencing factors of L. principis-rupprechtii seedlings’ natural regeneration were also investigated. The results showed that the spatial distribution patterns of Larix principis-rupprechtii seedlings were concentrated 0–5 m around adult trees when considering the main univariate distribution type of regeneration. There was a positive correlation at a scale of 1.5–4 m between seedlings and adult trees according to bivariate analyses. When the scale was increased, these relationships were no longer significant. Generally, adult trees raised regenerated L. principis-rupprechtii seedlings at a scale of 1.5–4 m. Principal component analysis showed that the understory herb diversity and litter layer had a negative correlation with the number of regenerated seedlings. There was also a weak relationship between regenerated numbers and canopy density. This study demonstrated that the main factors promoting natural regeneration were litter thickness, herb diversity, and the distance between adult trees and regenerated seedlings. Additionally, these findings will provide a basis for the late-stage and practical management of natural regeneration in northern China’s mountain ranges

The Citrus Laccase Gene CsLAC18 Contributes to Cold Tolerance

Plant laccases, as multicopper oxidases, play an important role in monolignol polymerization, and participate in the resistance response of plants to multiple biotic/abiotic stresses. However, little is currently known about the role of laccases in the cold stress response of plants. In this study, the laccase activity and lignin content of C. sinensis leaves increased after the low-temperature treatment, and cold treatment induced the differential regulation of 21 CsLACs, with 15 genes being upregulated and 6 genes being downregulated. Exceptionally, the relative expression level of CsLAC18 increased 130.17-fold after a 48-h treatment. The full-length coding sequence of CsLAC18 consists of 1743 nucleotides and encodes a protein of 580 amino acids, and is predominantly expressed in leaves and fruits. CsLAC18 was phylogenetically related to AtLAC17, and was localized in the cell membrane. Overexpression of CsLAC18 conferred enhanced cold tolerance on transgenic tobacco; however, virus-induced gene silencing (VIGS)-mediated suppression of CsLAC18 in Poncirus trifoliata significantly impaired resistance to cold stress. As a whole, our findings revealed that CsLAC18 positively regulates a plant&rsquo;s response to cold stress, providing a potential target for molecular breeding or gene editing