Primetime Crime and Its Influence on Public Perception

Since the television became more readily available to the American public in the 1940s and 50s, television shows have captured the attention of the nation. While television programs and televisions themselves have changed since then there are a few constants, one being the continued popularity of crime shows. From Sunday to Saturday during ‘prime time’ on just the four major networks, there are over fifteen hours of crime programming. The shows aim to entertain, leading them to show many inaccuracies about crime and the justice system in America. Studies have shown that most white Americans receive their information about crime and the justice system from the media. It would be naive to believe that they only would rely on the skewed perception of crime that the news media presents and pretend that the entertainment media plays no role in shaping their perception of crime. Through a study of eleven top crime shows in recent years, we will see the inaccuracies that have been portrayed to the public and which may in the future effect public policy

Disordered domains in chromatin-binding proteins.

Chromatin comprises proteins, DNA and RNA, and its function is to condense and package the genome in a way that allows the necessary transactions such as transcription, replication and repair to occur in a highly organised and regulated manner. The packaging of chromatin is often thought of in a hierarchical fashion starting from the most basic unit of DNA packaging, the nucleosome, to the condensation of nucleosomal 'beads on a string' by linker histones to form the 30-nm fibre and eventually large chromatin domains. However, a picture of a more heterogeneous, dynamic and liquid-like assembly is emerging, in which intrinsically disordered proteins (IDPs) and proteins containing intrinsically disordered regions (IDRs) play a central role. Disorder features at all levels of chromatin organisation, from the histone tails, which are sites of extensive post-translational modification (PTM) that change the fate of the underlying genomic information, right through to transcription hubs, and the recently elucidated roles of IDPs and IDRs in the condensation of large regions of the genome through liquid-liquid phase separation

The OneTogether collaborative approach to reduce the risk of surgical site infection: identifying the challenges to assuring best practice

Background: Surgical site infections (SSI) account for 16% of healthcare associated infections, and are associated with considerable morbidity, mortality and increased costs of care. Ensuring evidence-based practice to prevent SSI is incorporated across the patient’s surgical journey is complex. OneTogether is a quality improvement collaborative of infection prevention and operating department specialists, formed to support the spread and adoption of best practice to prevent SSI. This paper describes the findings of an expert workshop on infection prevention in operating departments. Methods: A total of 84 delegates from 75 hospitals attended the workshop, comprising 46 (55%) theatre nurses/operating department practitioners; 16 (19%) infection control practitioners and 22 (26%) other healthcare practitioners. Discussion focused on evidence, policy implementation and barriers to best practice. Responses were synthesised into a narrative review. Results: Delegates reported significant problems in translating evidence-based guidance into everyday practice, lack of local polices and poor compliance. Major barriers were lack of leadership, poorly defined responsibilities, and lack of knowledge/training. Conclusions: This workshop has provided important insights into major challenges in assuring compliance with best practice in relation to the prevention of SSI. The OneTogether partnership aims to support healthcare practitioners to improve the outcomes of patients undergoing surgery by reducing the risk of SSI

Proposed Allosteric Inhibitors Bind to the ATP Site of CK2α.

CK2α is a ubiquitous, well-studied kinase that is a target for small-molecule inhibition, for treatment of cancers. While many different classes of adenosine 5'-triphosphate (ATP)-competitive inhibitors have been described for CK2α, they tend to suffer from significant off-target activity and new approaches are needed. A series of inhibitors of CK2α has recently been described as allosteric, acting at a previously unidentified binding site. Given the similarity of these inhibitors to known ATP-competitive inhibitors, we have investigated them further. In our thorough structural and biophysical analyses, we have found no evidence that these inhibitors bind to the proposed allosteric site. Rather, we report crystal structures, competitive isothermal titration calorimetry (ITC) and NMR, hydrogen-deuterium exchange (HDX) mass spectrometry, and chemoinformatic analyses that all point to these compounds binding in the ATP pocket. Comparisons of our results and experimental approach with the data presented in the original report suggest that the primary reason for the disparity is nonspecific inhibition by aggregation

Characterization of the interaction between HMGB1 and H3-a possible means of positioning HMGB1 in chromatin.

High mobility group protein B1 (HMGB1) binds to the internucleosomal linker DNA in chromatin and abuts the nucleosome. Bending and untwisting of the linker DNA results in transmission of strain to the nucleosome core, disrupting histone/DNA contacts. An interaction between H3 and HMGB1 has been reported. Here we confirm and characterize the interaction of HMGB1 with H3, which lies close to the DNA entry/exit points around the nucleosome dyad, and may be responsible for positioning of HMGB1 on the linker DNA. We show that the interaction is between the N-terminal unstructured tail of H3 and the C-terminal unstructured acidic tail of HMGB1, which are presumably displaced from DNA and the HMG boxes, respectively, in the HMGB1-nucleosome complex. We have characterized the interaction by nuclear magnetic resonance spectroscopy and show that it is extensive for both peptides, and appears not to result in the acquisition of significant secondary structure by either partner

Characterisation of FUT4 and FUT6 α-(1 → 2)-fucosyltransferases reveals that absence of root arabinogalactan fucosylation increases Arabidopsis root growth salt sensitivity.

Plant type II arabinogalactan (AG) polysaccharides are attached to arabinogalactan proteins (AGPs) at hydroxyproline residues, and they are very diverse and heterogeneous structures. The AG consists of a β-(1 → 3)-linked galactan backbone with β-(1 → 6)-galactan side chains that are modified mainly with arabinose, but they may also contain glucuronic acid, rhamnose or other sugars. Here, we studied the positions of fucose substitutions in AGPs, and we investigated the functions of this fucosylation. Monosaccharide analysis of Arabidopsis leaf AGP extracts revealed a significant reduction in L-Fucose content in the fut4 mutant, but not in the fut6 mutant. In addition, Fucose was reduced in the fut4 mutant in root AGP extracts and was absent in the fut4/fut6 mutant. Curiously, in all cases reduction of fucose was accompanied with a reduction in xylose levels. The fucosylated AGP structures in leaves and roots in wild type and fut mutant plants were characterised by sequential digestion with AG specific enzymes, analysis by Polysaccharide Analysis using Carbohydrate gel Electrophoresis, and Matrix Assisted Laser Desorption/Ionisation (MALDI)-Time of Flight Mass spectrometry (MS). We found that FUT4 is solely responsible for the fucosylation of AGPs in leaves. The Arabidopsis thaliana FUT4 and FUT6 genes have been previously proposed to be non-redundant AG-specific fucosyltransferases. Unexpectedly, FUT4 and FUT6 enzymes both fucosylate the same AGP structures in roots, suggesting partial redundancy to each other. Detailed structural characterisation of root AGPs with high energy MALDI-Collision Induced Dissociation MS and NMR revealed an abundant unique AG oligosaccharide structure consisting of terminal xylose attached to fucose. The loss of this structure in fut4/fut6 mutants explains the reduction of both fucose and xylose in AGP extracts. Under salt-stress growth conditions the fut4/fut6 mutant lacking AGP fucosylation exhibited a shorter root phenotype than wild type plants, implicating fucosylation of AGPs in maintaining proper cell expansion under these conditions

Characterization of chromoshadow domain-mediated binding of heterochromatin protein 1α (HP1α) to histone H3.

The chromoshadow domain (CSD) of heterochromatin protein 1 (HP1) was recently shown to contribute to chromatin binding and transcriptional regulation through interaction with histone H3. Here, we demonstrate the structural basis of this interaction for the CSD of HP1α. This mode of H3 binding is dependent on dimerization of the CSD and recognition of a PxVxL-like motif, as for other CSD partners. NMR chemical shift mapping showed that the H3 residues that mediate the CSD interaction occur in and adjacent to the αN helix just within the nucleosome core. Access to the binding region would require some degree of unwrapping of the DNA near the nucleosomal DNA entry/exit site

Development of an oligosaccharide library to characterise the structural variation in glucuronoarabinoxylan in the cell walls of vegetative tissues in grasses.

BACKGROUND: Grass glucuronoarabinoxylan (GAX) substitutions can inhibit enzymatic degradation and are involved in the interaction of xylan with cell wall cellulose and lignin, factors which contribute to the recalcitrance of biomass to saccharification. Therefore, identification of xylan characteristics central to biomass biorefining improvement is essential. However, the task of assessing biomass quality is complicated and is often hindered by the lack of a reference for a given crop. RESULTS: In this study, we created a reference library, expressed in glucose units, of Miscanthus sinensis GAX stem and leaf oligosaccharides, using DNA sequencer-Assisted Saccharide analysis in high throughput (DASH), supported by liquid chromatography (LC), nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). Our analysis of a number of grass species highlighted variations in substitution type and frequency of stem and leaf GAX. In miscanthus, for example, the β-Xylp-(1 → 2)-α-Araf-(1 → 3) side chain is more abundant in leaf than stem. CONCLUSIONS: The reference library allows fast identification and comparison of GAX structures from different plants and tissues. Ultimately, this reference library can be used in directing biomass selection and improving biorefining

Highly disordered histone H1-DNA model complexes and their condensates.

Disordered proteins play an essential role in a wide variety of biological processes, and are often posttranslationally modified. One such protein is histone H1; its highly disordered C-terminal tail (CH1) condenses internucleosomal linker DNA in chromatin in a way that is still poorly understood. Moreover, CH1 is phosphorylated in a cell cycle-dependent manner that correlates with changes in the chromatin condensation level. Here we present a model system that recapitulates key aspects of the in vivo process, and also allows a detailed structural and biophysical analysis of the stages before and after condensation. CH1 remains disordered in the DNA-bound state, despite its nanomolar affinity. Phase-separated droplets (coacervates) form, containing higher-order assemblies of CH1/DNA complexes. Phosphorylation at three serine residues, spaced along the length of the tail, has little effect on the local properties of the condensate. However, it dramatically alters higher-order structure in the coacervate and reduces partitioning to the coacervate phase. These observations show that disordered proteins can bind tightly to DNA without a disorder-to-order transition. Importantly, they also provide mechanistic insights into how higher-order structures can be exquisitely sensitive to perturbation by posttranslational modifications, thus broadening the repertoire of mechanisms that might regulate chromatin and other macromolecular assemblies

Structural insights into the mechanism of negative regulation of single-box high mobility group proteins by the acidic tail domain.

The Drosophila and plant (maize) functional counterparts of the abundant vertebrate chromosomal protein HMGB1 (HMG-D and ZmHMGB1, respectively) differ from HMGB1 in having a single HMG box, as well as basic and acidic flanking regions that vary greatly in length and charge. We show that despite these variations, HMG-D and ZmHMGB1 exist in dynamic assemblies in which the basic HMG boxes and linkers associate with their intrinsically disordered, predominantly acidic, tails in a manner analogous to that observed previously for HMGB1. The DNA-binding surfaces of the boxes and linkers are occluded in "auto-inhibited" forms of the protein, which are in equilibrium with transient, more open structures that are "binding-competent." This strongly suggests that the mechanism of auto-inhibition may be a general one. HMG-D and ZmHMGB1 differ from HMGB1 in having phosphorylation sites in their tail and linker regions. In both cases, in vitro phosphorylation of serine residues within the acidic tail stabilizes the assembled form, suggesting another level of regulation for interaction with DNA, chromatin, and other proteins that is not possible for the uniformly acidic (hence unphosphorylatable) tail of HMGB1.This work was supported by the Biotechnology and Biological Sciences Research Council through the award of Grant BB/D002257/1 (to J. O. T.) and a grant from the Deutsche Forschungsgemeinschaft (DFG) (to K. D. G.).This is the final published version. It first appeared at http://www.jbc.org/content/289/43/29817.long