Localization and function of histone methylation at active genes in "Drosophila"

In the eukaryotic nucleus, DNA is bound by an octamer of four core histones forming the fundamental repeating unit of chromatin, called the nucleosome. Presenting a barrier to virtually all DNA-templated events, nucleosomal packaging is subject to dynamic alterations. Nucleosomal histone modifications have emerged as a major determinant of chromatin structure and gene expression. Genome-wide and local profiling of chromatin structure in Drosophila cells reveals a complex landscape of histone methylation marks along the body of active genes. Methylation of lysine 4 and lysine 79 of histone H3 coincide at promoters and gradually decrease towards the 3’ end. Conversely, H3 lysine 36 methylation states show very different distribution patterns. Dimethylation of H3K36 peaks downstream of promoter-proximal K4 methylation, whereas trimethylation accumulates towards the 3’ end of genes. These topographic differences do not reflect deposition-coupled targeting by histone variant H3.3 but instead argue for discrete regulation and function of active methylation marks during transcription elongation. Indeed, H3K36 di- and trimethylation states rely on two distinct HMTs and display opposite effects on H4K16 acetylation at autosomal genes. This crosstalk is reminiscent of K36me3-dependent deacetylase recruitment in budding yeast, yet it is more intricate as dimethylation appears to signal for increased H4K16 acetylation. Apart from its autosomal function, H3K36me3 has a separate role to enhance H4K16 acetylation at the dosage-compensated X chromosome in male Drosophila cells. This additional function most likely involves MSL complex recruitment to dosage compensated genes. Together, our results reveal a complex pattern of histone methylation marks at active genes, which may enable dynamic chromatin changes during transcription elongation in higher eukaryotes. Furthermore, the context-dependent readout of H3K36me3 implies that methylation marks act as general signaling platforms, which impart their specificity by recruiting effector proteins to characteristic landmarks along the transcription unit

S18RS SGR No. 1 (TOPS)

A RESOLUTION To strongly urge the Louisiana State Legislature to FULLY fund the Taylor Opportunity Program for Students (TOPS) during the 2018 Legislative sessio

Smart Cities and M³: Rapid Research, Meaningful Metrics and Co-Design

The research described in this paper is undertaken under the banner of the smart city, a concept that captures the way urban spaces are re-made by the incursion of new technology. Much of smart is centred on converting everyday activities into data, and using this data to generate knowledge mediated by technology. Ordinary citizens, those that may have their lives impacted by the technology, usually are not properly involved in the ‘smartification’ process. Their perceptions, concerns and expectations should inform the conception and development of smart technologies at the same extent. How to engage general public with smart cities research is the central challenge for the Making Metrics Meaningful (MMM) project. Applying a rapid participatory method, ‘Imagine’ over a five-month period (March – July) the research sought to gain insights from the general public into novel forms of information system innovation. This brief paper describes the nature of the accelerated research undertaken and explores some of the themes which emerged in the analysis. Generic themes, beyond the remit of an explicit transport focus, are developed and pointers towards further research directions are discussed. Participatory methods, including engaging with self- selected transport users actively through both picture creation and programmatically specific musical ‘signatures’ as well as group discussion, were found to be effective in eliciting users’ own concerns, needs and ideas for novel information systems

Entanglement transfer from electron spins to photons in spin light-emitting diodes containing quantum dots

We show that electron recombination using positively charged excitons in single quantum dots provides an efficient method to transfer entanglement from electron spins onto photon polarizations. We propose a scheme for the production of entangled four-photon states of GHZ type. From the GHZ state, two fully entangled photons can be obtained by a measurement of two photons in the linear polarization basis, even for quantum dots with observable fine structure splitting for neutral excitons and significant exciton spin decoherence. Because of the interplay of quantum mechanical selection rules and interference, maximally entangled electron pairs are converted into maximally entangled photon pairs with unity fidelity for a continuous set of observation directions. We describe the dynamics of the conversion process using a master-equation approach and show that the implementation of our scheme is feasible with current experimental techniques.Comment: 5 pages, 2 figures. v2: Extended scheme, revised version. v3: Minor additions and extended title, published versio

Is it worth subsoil testing for Nitrogen?

In WA, soil testing for mineral N (ammonium plus nitrate) has traditionally been taken from the top 0-0.1 m. Farmers and advisors are now interested in deeper soil testing, in order to know how much mineral N occurs at depth and what this may mean in terms of fertiliser N application decisions. Accounting for topsoil and subsoil test level in N fertiliser use varies markedly among growers and advisors depending on; their own historic applications; use of nitrogen decision support tools (N-DSS’s) such as Yield Prophet simulations or SYN. Other growers use approximate total soil profile N and then add N fertiliser required to reach target yield (i.e. 45 kg N/ha for 1 t/ha of grain). The main question this paper is addressing is “Do I need to soil test to depth for better N decisions?” To answer this we needed to understand: 1. Where in the profile the subsoil N occurs and if it is related to topsoil N, 2. How effective is the subsoil in supplying N for the crop – which depends on root access to subsoil N as affected by subsoil constraints and N leaching, 3. What does this mean for N recommendation systems based on soil testing? and 4. Given the seasonal interaction with yield response, will the subsoil N test results reduce the errors in recommendations enough to justify this extra complexity, cost and effort

Quasi-deterministic generation of entangled atoms in a cavity

We present a scheme to generate a maximally entangled state of two three-level atoms in a cavity. The success or failure of the generation of the desired entangled state can be determined by detecting the polarization of the photon leaking out of the cavity. With the use of an automatic feedback, the success probability of the scheme can be made to approach unity.Comment: 10 pages, 3 figure

Differential human brain activation by vertical and horizontal global visual textures

Mid-level visual processes which integrate local orientation information for the detection of global structure can be investigated using global form stimuli of varying complexity. Several lines of evidence suggest that the identification of concentric and parallel organisations relies on different underlying neural substrates. The current study measured brain activation by concentric, horizontal parallel, and vertical parallel arrays of short line segments, compared to arrays of randomly oriented segments. Six subjects were scanned in a blocked design functional magnetic resonance imaging experiment. We compared percentage BOLD signal change during the concentric, horizontal and vertical blocks within early retinotopic areas, the fusiform face area and the lateral occipital complex. Unexpectedly, we found that vertical and horizontal parallel forms differentially activated visual cortical areas beyond V1, but in general, activations to concentric and parallel forms did not differ. Vertical patterns produced the highest percentage signal change overall and only area V3A showed a significant difference between concentric and parallel (horizontal) stimuli, with the former better activating this area. These data suggest that the difference in brain activation to vertical and horizontal forms arises at intermediate or global levels of visual representation since the differential activity was found in mid-level retinotopic areas V2 and V3 but not in V1. This may explain why earlier studies—using methods that emphasised responses to local orientation—did not discover this vertical-horizontal anisotrop

The role of B cells in periodontitis

Introduction: Varying degrees of periodontal disease affect the majority of the population. Severe forms of periodontitis have a considerable impact on oral health and quality of life. Periodontitis results from imbalances in the oral microbiome and the host immune response. The mainstay of periodontal treatment – removal of dental plaque – is only partially successful. B cells infiltrate the gingiva of periodontitis patients, but their role in pathology has not been well characterised. The overarching aim of this research was to better characterise the role of B cells in periodontitis. Periodontitis shares similarities in risk factors and aspects of immunopathology with rheumatoid arthritis. Epidemiological evidence suggests patients with rheumatoid arthritis are more likely to have periodontitis, which cannot be completely explained by shared risk factors. This has led to the hypothesis that the two diseases are immunologically linked, and that periodontitis may precede, and cause, rheumatoid arthritis. A further objective of this research was to investigate whether the autoimmunity characteristic of rheumatoid arthritis emerges in periodontitis. Results: B cell infiltrate in the gingiva of periodontitis patients was confirmed. Periodontitis patients were found to have elevated serum titers of anti-citrullinated peptide antibodies which were generally below the diagnostic threshold for rheumatoid arthritis, and were reduced following non-surgical periodontal treatment. In a murine model of periodontitis, subtle changes to B cell phenotype were observed in tissues regional to the oral cavity in mice with periodontitis, at an early stage of disease. Such changes included increased B cell expression of receptor activator of NfκB ligand in the gingiva, and increased proportions of GC B cells in the draining lymph nodes. Some of these trends were enhanced in mice with periodontitis exacerbated by interleukin-33 treatment. B cell-deficient mice were protected from the alveolar bone loss normally induced in the model of periodontitis. Conclusion: B cells form a substantial proportion of the inflammatory infiltrate in the gingiva of periodontitis patients. Treatment of periodontitis can reduce titers of anti-citrullinated peptide antibodies in patients, potentially reducing their risk of developing rheumatoid arthritis. Evidence from B cell-deficient mice suggests that B cells contribute to pathological alveolar bone loss. Therefore, B cells may be worthy of targeting therapeutically in periodontitis

Antioxidant-rich beetroot juice does not adversely affect acute neuromuscular adaptation following eccentric exercise

This study examined the effects of beetroot juice on the repeated bout effect (RBE) to eccentric exercise. Twenty-nine recreationally active males performed two bouts of 100-drop jumps, separated by 14–21 days. Using a double-blind, independent groups design, participants consumed either a higher dose beetroot juice (H-BT; 250 ml, n = 10), a lower dose beetroot juice (L-BT; 125 ml, n = 9) or an isocaloric placebo (PLA; 250 ml, n = 10) for 3 days after bout 1; no drinks were consumed after bout 2. Maximal isometric voluntary contraction (MIVC), countermovement jump (CMJ), pressure-pain threshold (PPT) and creatine kinase (CK) were measured pre, post, 24, 48 and 72 h following both bouts. In bout 2, CMJ and MIVC recovered quicker and CK activity was attenuated (versus bout 1) (P < 0.05) in all groups, demonstrating an RBE. At 24 h post bout 1, MIVC was 84.1 ± 16.1, 83.6 ± 11.6, 79.7 ± 15.1% relative to baseline values in the H-BT, L-BT and PLA groups, respectively; at 24 h post bout 2, MIVC recovered to 90.7 ± 13.7, 92.9 ± 6.9, 87.8 ± 6.9, in the H-BT, L-BT and PLA groups, respectively. These findings suggest that supplementation with antioxidant-rich beetroot juice does not adversely affect acute adaptations to a bout of eccentric exercise