Crystal Structure of the C-Terminal Cytoplasmic Domain of Non-Structural Protein 4 from Mouse Hepatitis Virus A59

BACKGROUND:The replication of coronaviruses takes place on cytoplasmic double membrane vesicles (DMVs) originating in the endoplasmic reticulum (ER). Three trans-membrane non-structural proteins, nsp3, nsp4 and nsp6, are understood to be membrane anchors of the coronavirus replication complex. Nsp4 is localized to the ER membrane when expressed alone but is recruited into the replication complex in infected cells. It is revealed to contain four trans-membrane regions and its N- and C-termini are exposed to the cytosol. METHODOLOGY/PRINCIPAL FINDINGS:We have determined the crystal structures of the C-terminal hydrophilic domain of nsp4 (nsp4C) from MHV strain A59 and a C425S site-directed mutant. The highly conserved 89 amino acid region from T408 to Q496 is shown to possess a new fold. The wild-type (WT) structure features two monomers linked by a Cys425-Cys425 disulfide bond in one asymmetric unit. The monomers are arranged with their N- and C-termini in opposite orientations to form an "open" conformation. Mutation of Cys425 to Ser did not affect the monomer structure, although the mutant dimer adopts strikingly different conformations by crystal packing, with the cross-linked C-termini and parallel N-termini of two monomers forming a "closed" conformation. The WT nsp4C exists as a dimer in solution and can dissociate easily into monomers in a reducing environment. CONCLUSIONS/SIGNIFICANCE:As nsp4C is exposed in the reducing cytosol, the monomer of nsp4C should be physiological. This structure may serve as a basis for further functional studies of nsp4

Mapping the tuberculosis scientific landscape among BRICS countries: a bibliometric and network analysis

BACKGROUND The five BRICS (Brazil, Russian, Indian, China, and South Africa) countries bear 49% of the world’s tuberculosis (TB) burden and they are committed to ending tuberculosis. OBJECTIVES The aim of this paper is to map the scientific landscape related to TB research in BRICS countries. METHODS Were combined bibliometrics and social network analysis techniques to map the scientific publications related to TB produced by the BRICS. Was made a descriptive statistical data covering the full period of analysis (1993-2016) and the research networks were made for 2007-2016 (8,366 records). The bubble charts were generated by VantagePoint and the networks by the Gephi 0.9.1 software (Gephi Consortium 2010) from co-occurrence matrices produced in VantagePoint. The Fruchterman-Reingold algorithm provided the networks’ layout. FINDINGS During the period 1993-2016, there were 38,315 peer-reviewed, among them, there were 11,018 (28.7%) articles related by one or more authors in a BRICS: India 38.7%; China 23.8%; South Africa 21.1%; Brazil 13.0%; and Russia 4.5% (The total was greater than 100% because our criterion was all papers with at least one author in a BRICS). Among the BRICS, there was greater interaction between India and South Africa and organisations in India and China had the highest productivity; however, South African organisations had more interaction with countries outside the BRICS. Publications by and about BRICS generally covered all research areas, especially those in India and China covered all research areas, although Brazil and South Africa prioritised infectious diseases, microbiology, and the respiratory system. MAIN CONCLUSIONS An overview of BRICS scientific publications and interactions highlighted the necessity to develop a BRICS TB research plan to increase efforts and funding to ensure that basic science research successfully translates into products and policies to help end the TB epidemic

Utilizing the Hippo pathway as a therapeutic target for combating endocrine-resistant breast cancer

Abstract Drug resistance is always a great obstacle in any endocrine therapy of breast cancer. Although the combination of endocrine therapy and targeted therapy has been shown to significantly improve prognosis, refractory endocrine resistance is still common. Dysregulation of the Hippo pathway is often related to the occurrence and the development of many tumors. Targeted therapies of this pathway have played important roles in the study of triple negative breast cancer (TNBC). Targeting the Hippo pathway in combination with chemotherapy or other targeted therapies has been shown to significantly improve specific antitumor effects and reduce cancer antidrug resistance. Further exploration has shown that the Hippo pathway is closely related to endocrine resistance, and it plays a “co-correlation point” role in numerous pathways involving endocrine resistance, including related pathways in breast cancer stem cells (BCSCs). Agents and miRNAs targeting the components of the Hippo pathway are expected to significantly enhance the sensitivity of breast cancer cells to endocrine therapy. This review initially explains the possible mechanism of the Hippo pathway in combating endocrine resistance, and it concludes by recommending endocrine therapy in combination with therapies targeting the Hippo pathway in the study of endocrine-resistant breast cancers

A data set of bloodstain patterns for teaching and research in bloodstain pattern analysis: Gunshot backspatters

This is a data set of blood spatter patterns scanned at high resolution, generated in controlled experiments. The spatter patterns were generated with a rifle or a handgun with varying ammunition. The resulting atomized blood droplets travelled opposite to the bullet direction, generating a gunshot backspatter on a poster board target sheet. Fresh blood with anticoagulants was used; its hematocrit and temperature were measured. The main parameters of the study were the bullet shape, size and speed, and the distance between the blood source and target sheet. Several other parameters were explored in a less systematic way. This new and original data set is suitable for training or research purposes in the forensic discipline of bloodstain pattern analysis.This article is published as Attinger, Daniel, Yu Liu, Ricky Faflak, Yalin Rao, Bryce A. Struttman, Kris De Brabanter, Patrick M. Comiskey, and Alexander L. Yarin. "A data set of bloodstain patterns for teaching and research in bloodstain pattern analysis: Gunshot backspatters." Data in brief 22 (2019): 269-278.</p

Data collection and refinement statistics.

a<p><i>R_merge</i> = Σ_hΣ_l | I_ih−h> |/Σ_hΣ_I h>, where h> is the mean of the observations I_ih of reflection h.</p>b<p><i>R_work</i> = Σ( ||F_p(obs)|−|F_p(calc)||)/Σ|F_p(obs)|; <i>R_free</i>  = R factor for a selected subset (5%) of the reflections that was not included in prior refinement calculations.</p>c<p>Numbers in parentheses are corresponding values for the highest resolution shell.</p

The molecular surface model of the monomer from nsp4C (T408-Q496) WT dimer and mutant C425S.

<p>Electrostatic potential is mapped on the surface, with positive charged region colored in blue and negative charged region in red. Both molecules in one asymmetric unit of the WT nsp4C dimer and mutant C425S are shown in three orientations. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006217#pone-0006217-g003" target="_blank">Fig. 3A and 3B</a> represents molecule A and molecule B of the WT nsp4C dimer respectively; while <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006217#pone-0006217-g003" target="_blank">Fig. 3C</a> represents the monomer of the C425S mutant. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006217#pone-0006217-g003" target="_blank">Fig. 3D</a> represents the superposition of molecule A (gold) and B (magenta) from WT and the monomer of the C425S mutant (green), Cys425 is shown in stick representation, with the carbon, nitrogen, oxygen, and sulfur atoms colored yellow, blue, red, and green, respectively; and also the crystal packing of WT nsp4C (magenta), symmetry-related molecules are colored in green, and the molecule forming the equivalent of the C425S mutant dimer is colored in blue. Selected amino acids are labeled, and the figure is drawn by PyMol <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006217#pone.0006217-DeLano1" target="_blank">[47]</a>.</p

Monomer structure of nsp4C possess a new fold.

<p>A. Stereo view of the nsp4C monomer Cα backbone trace. Positions of selected residues and the N- and C-termini are labeled. B. Topology of the nsp4C monomer. β-strands are shown in arrows, and α-helices in cylinders. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006217#pone-0006217-g002" target="_blank">Fig. 2A</a> was drawn with the programs with PyMol <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006217#pone.0006217-DeLano1" target="_blank">[47]</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006217#pone-0006217-g002" target="_blank">2B</a> with TopDraw.</p