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The c-Myb gene encodes a transcription factor that regulates cell proliferation, differentiation, and apoptosis through protein-protein interaction and transcriptional regulation of signaling pathways. The protein is frequently overexpressed in human leukemias, breast cancers, and other solid tumors suggesting that it is a bona fide oncogene. c-MYB is often overexpressed by translocation in human tumors with t(6;7)(q23;q34) resulting in c-MYB-TCRβ in T cell ALL, t(X;6)(p11;q23) with c-MYB-GATA1 in acute basophilic leukemia, and t(6;9)(q22-23;p23-24) with c-MYB-NF1B in adenoid cystic carcinoma. Antisense oligonucleotides to c-MYB were developed to purge bone marrow cells to eliminate tumor cells in leukemias. Recently, small molecules that inhibit c-MYB activity have been developed to disrupt its interaction with p300. The Dmp1 (cyclin D binding myb-like protein 1; Dmtf1) gene was isolated through its virtue for binding to cyclin D2. It is a transcription factor that has a Myb-like repeat for DNA binding. The Dmtf1 protein directly binds to the Arf promoter for transactivation and physically interacts with p53 to activate the p53 pathway. The gene is hemizygously deleted in 35-42% of human cancers and is associated with longer survival. The significances of aberrant expression of c-MYB and DMTF1 proteins in human cancers and their clinical significances are discussed. [ABSTRACT FROM AUTHOR]

Recent studies have indicated that EGR1 is a direct regulator of tumor suppressors including TGFβ1, PTEN, and p53. The Myb-like transcription factor Dmp1 is a physiological regulator of the Arf-p53 pathway through transactivation of the Arf promoter and physical interaction of p53. The Dmp1 promoter has binding sites for Egr proteins, and Egr1 is a target for Dmp1. Crosstalks between p53 and PTEN have been reported. The Egr1-Dmp1-Arf-p53-Pten pathway displays multiple modes of interaction with each other, suggesting the existence of a functional network of tumor suppressors that maintain normal cell growth and prevent the emergence of incipient cancer cells. [ABSTRACT FROM AUTHOR]

The use of molecular biomarkers assures that breast cancer (BC) patients receive optimal treatment. Established biomarkers, such as estrogen receptor, progesterone receptor, HER2, and Ki67, have been playing significant roles in the subcategorization of BC to predict the prognosis and decide the specific therapy to each patient. Antihormonal therapy using 4-hydroxytamoxifen or aromatase inhibitors have been employed in patients whose tumor cells express hormone receptors, while monoclonal antibody to HER2 has been administered to HER2-positive BCs. Although new therapeutic agents have been developed in the past few decades, many patients still die of the disease due to relapse; thus, novel molecular markers that predict therapeutic failure and those that can be targets for specific therapy are expected. We have chosen four of such molecules by reviewing recent publications, which are cyclin E, B-Myb, Twist, and DMP1β. The oncogenicity of these molecules has been demonstrated in vivo and/or in vitro through studies using transgenic mice or siRNAs, and their expressions have been shown to be associated with shortened overall or disease-free survival of BC patients. The former three molecules have been shown to accelerate epithelial-mesenchymal transition that is often associated with cancer stem cell-ness and metastasis; all these four can be novel therapeutic targets as well. Thus, large prospective studies employing immunohistochemistry will be needed to establish the predictive values of these molecules in patients with BC. [ABSTRACT FROM AUTHOR]

Cyclin D1 binds and activates cyclin-dependent kinases 4/6 (Cdk4/6) to phosphorylate the retinoblastoma (RB) family proteins, relieving E2F/DPs from the negative restraint of RB proteins and histone deacetylases (HDACs). The cyclin D-Cdk4/6 complexes activate cyclin E/Cdk2 through titration of the Cdk inhibitors p21Cip1/p27Kip1. Cyclin E/Cdk2 further phosphorylates RBs, thereby activating E2F/DPs, and cells enter the S-phase of the cell cycle. Cyclin D-Cdk4/6 also phosphorylates MEP50 subunit of the protein arginine methyltransferase 5 (PRMT5), which cooperates with cyclin D1 to drive lymphomagenesis in vivo. Activated PRMPT5 causes arginine methylation of p53 to suppress expression of proapoptotic and antiproliferative target genes, explaining the molecular mechanism for tumorigenesis. Cyclin D1 physically interacts with transcription factors such as estrogen receptor, androgen receptor, and Myb family proteins to regulate gene expression in Cdk-independent fashion. Dmp1 is a Myb-like protein that quenches the oncogenic signals from activated Ras or HER2 by inducing Arf/p53-dependent cell cycle arrest. Cyclin D1 binds to Dmp1 to activate both Arf and Ink4a promoters to induce cell cycle arrest or apoptosis in non-transformed cells to prevent them from neoplastic transformation. Dmp1 deficiency significantly accelerates mouse mammary tumorigenesis with reduced apoptosis and increased metastasis. Cyclin D1 interferes with ligand activation of PPAR? involved in cellular differentiation; it also physically interacts with HDACs and p300 to repress gene expression. It has also been shown that cyclin D1 accelerates tumorigenesis through transcriptional activation of miR-17/20 and Dicer1 which, in turn, represses cyclin D1 expression. Identification of cyclin D1-binding proteins/ promoters will be essential for further clarification of its biological activities. [ABSTRACT FROM AUTHOR]

Our recent study shows a pivotal role of Dmp1 in quenching hyperproliferative signals from HER2 to the Arf-p53 pathway as a safety mechanism to prevent breast carcinogenesis. To directly demonstrate the role of Dmp1 in preventing HER2/neu-driven oncogenic transformation, we established Flag-Dmp1α transgenic mice (MDTG) under the control of the mouse mammary tumor virus (MMTV) promoter. The mice were viable but exhibited poorly developed mammary glands with markedly reduced milk production; thus more than half of parous females were unable to support the lives of new born pups. The mammary glands of the MDTG mice had very low Ki-67 expression but high levels of Arf, Ink4a, p53, and p21Cip1, markers of senescence and accelerated aging. In all strains of generated MDTG;neu mice, tumor development was significantly delayed with decreased tumor weight. Tumors from MDTG;neu mice expressed Flag-Dmp1α and Ki-67 in a mutually exclusive fashion indicating that transgenic Dmp1α prevented tumor growth in vivo. Genomic DNA analyses showed that the Dmp1α transgene was partially lost in half of the MDTG;neu tumors, and Western blot analyses showed Dmp1α protein downregulation in 80% of the cases. Our data demonstrate critical roles of Dmp1 in preventing mammary tumorigenesis and raise the possibility of treating breast cancer by restoring Dmp1α expression. [ABSTRACT FROM AUTHOR]

Gain-of-function mutations in oncogenes and loss-of-function mutations in tumor suppressor genes (TSG) lead to cancer. In most human cancers, these mutations occur in somatic tissues. However, hereditary forms of cancer exist for which individuals are heterozygous for a germline mutation in a TSG locus at birth. The second allele is frequently inactivated by gene deletion, point mutation, or promoter methylation in classical TSGs that meet Knudson's two-hit hypothesis. Conversely, the second allele remains as wild-type, even in tumors in which the gene is haplo-insufficient for tumor suppression. This article highlights the importance of PTEN, APC, and other tumor suppressors for counteracting aberrant PI3K, β-catenin, and other oncogenic signaling pathways. We discuss the use of gene-engineered mouse models (GEMM) of human cancer focusing on Pten and Apc knockout mice that recapitulate key genetic events involved in initiation and progression of human neoplasia. Finally, the therapeutic potential of targeting these tumor suppressor and oncogene signaling networks is discussed. [ABSTRACT FROM AUTHOR]

Gain-of-function mutations in oncogenes and loss-of-function mutations in tumor suppressor genes (TSG) lead to cancer. In most human cancers, these mutations occur in somatic tissues. However, hereditary forms of cancer exist for which individuals are heterozygous for a germline mutation in a TSG locus at birth. The second allele is frequently inactivated by gene deletion, point mutation, or promoter methylation in classical TSGs that meet Knudson's two-hit hypothesis. Conversely, the second allele remains as wild-type, even in tumors in which the gene is haplo-insufficient for tumor suppression. This article highlights the importance of PTEN, APC, and other tumor suppressors for counteracting aberrant PI3K, β-catenin, and other oncogenic signaling pathways. We discuss the use of gene-engineered mouse models (GEMM) of human cancer focusing on Pten and Apc knockout mice that recapitulate key genetic events involved in initiation and progression of human neoplasia. Finally, the therapeutic potential of targeting these tumor suppressor and oncogene signaling networks is discussed. [ABSTRACT FROM AUTHOR]

The Nogo receptor (NgR), which was identified as a common receptor for three axon growth inhibitors associated with myelin, has been extensively characterized for its role in triggering growth cone collapse and arresting neurite/axon growth. Recent studies indicate that NgR is also expressed in nonneuronal cells and modulates macrophage responses during inflammation after peripheral nerve injury. In this article, we discuss the possibility that NgR might have wider effects on inflammation in a variety of neurological conditions ranging from central nervous system trauma to diseases such as multiple sclerosis or Alzheimer''s disease. [Copyright &y& Elsevier]

Summary: We report a role for Nogo receptors (NgRs) in macrophage efflux from sites of inflammation in peripheral nerve. Increasing numbers of macrophages in crushed rat sciatic nerves express NgR1 and NgR2 on the cell surface in the first week after injury. These macrophages show reduced binding to myelin and MAG in vitro, which is reversed by NgR siRNA knockdown and by inhibiting Rho-associated kinase. Fourteen days after sciatic nerve crush, regenerating nerves with newly synthesized myelin have fewer macrophages than cut/ligated nerves that lack axons and myelin. Almost all macrophages in the cut/ligated nerves lie within the Schwann cell basal lamina, while in the crushed regenerating nerves the majority migrate out. Furthermore, crush-injured nerves of NgR1- and MAG-deficient mice and Y-27632-treated rats show impaired macrophage efflux from Schwann cell basal lamina containing myelinated axons. These data have implications for the resolution of inflammation in peripheral nerve and CNS pathologies. [Copyright &y& Elsevier]

As part of a high-throughput structural analysis of SARS-coronavirus (SARS-CoV) proteins, we have solved the structure of the non-structural protein 9 (nsp9). This protein, encoded by ORF1a, has no designated function but is most likely involved with viral RNA synthesis. The protein comprises a single β-barrel with a fold previously unseen in single domain proteins. The fold superficially resembles an OB-fold with a C-terminal extension and is related to both of the two subdomains of the SARS-CoV 3C-like protease (which belongs to the serine protease superfamily). nsp9 has, presumably, evolved from a protease. The crystal structure suggests that the protein is dimeric. This is confirmed by analytical ultracentrifugation and dynamic light scattering. We show that nsp9 binds RNA and interacts with nsp8, activities that may be essential for its function(s). [Copyright &y& Elsevier]

Swine vesicular disease virus (SVDV) is an Enterovirus of the family Picornaviridae that causes symptoms indistinguishable from those of foot-and-mouth disease virus. Phylogenetic studies suggest that it is a recently evolved genetic sublineage of the important human pathogen coxsackievirus B5 (CBV5), and in agreement with this, it has been shown to utilize the coxsackie and adenovirus receptor (CAR) for cell entry. The 3.0-Å crystal structure of strain UK/27/72 SVDV (highly virulent) reveals the expected similarity in core structure to those of other picornaviruses, showing most similarity to the closest available structure to CBVS, that of coxsackievirus B3 (CBV3). Features that help to cement together and rigidify the protein subunits are extended in this virus, perhaps explaining its extreme tolerance of environmental factors. Using the large number of capsid sequences available for both SVDV and CBVS, we have mapped the amino acid substitutions that may have occurred during the supposed adaptation of SVDV to a new host onto the structure of SVDV and a model of the SVDV/CAR complex generated by reference to the cryo-electron microscopy-visualized complex of CBV3 and CAR. The changes fall into three clusters as follows: one lines the fivefold pore, a second maps to the CAR-binding site and partially overlaps the site for decay accelerating factor (DAF) to bind to echovirus 7 (ECHO7), and the third lies close to the fivefold axis, where the low-density lipoprotein receptor binds to the minor group of rhinoviruses. Later changes in SVDV (post-1971) map to the first two clusters and may, by optimizing recognition of a pig CAR and/or DAF homologue, have improved the adaptation of the virus to pigs. [ABSTRACT FROM AUTHOR]

Focuses on the regeneration of the central nervous system. Complexity of the regenerative response from an injured central neuron; Effects of the application of trophic support to the lesion site for axotomized neurons; Possible blockade of inhibitory action of myelin-associated molecules and glial elements with antibodies.

The Statistics Teaching Inventory (STI) was designed to assess the teaching practices of U.S.-based, college-level introductory statistics instructors in a variety of institutions and departments. This instrument has now been updated to reflect current trends and recommendations in statistics education. In this study, we used the STI to examine the current state of the curricular and instructional practices being used by U.S.-based, college-level introductory statistics instructors. We explore the extent to which instructors report that their introductory statistics courses are aligned with recommended practices as outlined by the 2016 GAISE College Report. Data were collected from a sample of college-level U.S.-based, college-level introductory statistics instructors. Results based on 228 usable responses indicated that instructors, by-and-large, tended to be following the GAISE recommendations, especially related to content. However, courses may not yet be aligned with newer content recommendations (e.g., provide students opportunities to work with multivariate data), and there is still a large percentage of instructors that are not embracing student-oriented pedagogies and assessment methods. for this article are available online. [ABSTRACT FROM AUTHOR]

Heparan sulfate has an important role in cell entry by foot-and-mouth disease virus (FMDV). We find that subtype O1 FMDV binds this glycosaminoglycan with a high affinity by immobilizing a specific highly abundant motif of sulfated sugars. The binding site is a shallow depression on the virion surface, located at the junction of the three major capsid proteins, VP1, VP2 and VP3. Two pre-formed sulfate-binding sites control receptor specificity. Residue 56 of VP3, an arginine in this virus, is critical to this recognition, forming a key component of both sites. This residue is a histidine in field isolates of the virus, switching to an arginine in adaptation to tissue culture, forming the high affinity heparan sulfate-binding site. We postulate that this site is a conserved feature of FMDVs, such that in the infected animal there is a biological advantage to low affinity, or more selective, interactions with glycosaminoglycan receptors. [ABSTRACT FROM AUTHOR]

ABSTRACT. Forty-one children with sex chromosome anomalies identified from the chromosome screening of a newborn population were blindly evaluated by a speech-language pathologist, along with a control group of 31 siblings. 47,XXX girls and 47,XXY boys were found to have increased problems in auditory perception, receptive language, and expressive language; the problems of the 47,XXY boys were less severe than those of the 47,XXX group, and reflected specific deficits in their ability to process linguistic information rather than a deficit in comprehension. An increased occurrence of speech production problems among the 45,X girls was associated with the presence of oral/structural malformations that often had no measurable effect on their production of speech sounds. Although the 45,X girls and 47,XYY boys had no significant increase of problems in auditory reception, receptive language, and expressive language, the trend of the data suggested more difficulty than in the control groups. The mosaic children were not different from the control subjects. Some children in all groups were found to have normal speech and language development. [ABSTRACT FROM AUTHOR]

Lung cancer is the leading cause of cancer deaths in the world, and accounts for more solid tumor deaths than any other carcinomas. The prognostic values of DMP1, ARF, and p53-loss are unknown in lung cancer. We have conducted survival analyses of non-small cell lung cancer (NSCLC) patients from the University of Minnesota VA hospital and those from the Wake Forest University Hospital. Loss of Heterozygosity (LOH) for hDMP1 was found in 26 of 70 cases (37.1%), that of the ARF/INK4a locus was found in 33 of 70 (47.1%), and that of the p53 locus in 43 cases (61.4%) in the University of Minnesota samples. LOH for hDMP1 was associated with favorable prognosis while that of p53 predicted worse prognosis. The survival was much shorter for ARF-loss than INK4a-loss, emphasizing the importance of ARF in human NSCLC. The adverse effect of p53 LOH on NSCLC patients' survival was neutralized by simultaneous loss of the hDMP1 locus in NSCLC and breast cancer, suggesting the possible therapy of epithelial cancers with metastatic ability. [ABSTRACT FROM AUTHOR]

A surprisingly strong spin rate dependence of 15N and 13C NMR T1 times in magic angle spinning experiments on solid peptides is demonstrated. Using a variety of isotopomers, the phenomenon is shown to be the result of chemical shift anisotropy-mediated spin diffusion. This effect has the potential to be used to detect long-range distance constraints in macromolecular systems. [ABSTRACT FROM AUTHOR]

The third complementary‐determining regions of the heavy‐chain (CDR3H) variable regions (VH) of some cattle antibodies are highly extended, consisting of 48 or more residues. These 'ultralong' CDR3Hs form β‐ribbon stalks that protrude from the surface of the antibody with a disulfide cross‐linked knob region at their apex that dominates antigen interactions over the other CDR loops. The structure of the Fab fragment of a naturally paired bovine ultralong antibody (D08), identified by single B‐cell sequencing, has been determined to 1.6 Å resolution. By swapping the D08 native light chain with that of an unrelated antigen‐unknown ultralong antibody, it is shown that interactions between the CDR3s of the variable domains potentially affect the fine positioning of the ultralong CDR3H; however, comparison with other crystallographic structures shows that crystalline packing is also a major contributor. It is concluded that, on balance, the exact positioning of ultralong CDR3H loops is most likely to be due to the constraints of crystal packing. [ABSTRACT FROM AUTHOR]

A list of articles about statistics education is presented including "Bridging the Gap Between Tools for Learning and for Doing Statistics," "Motivating Inquiry in Statistics and Probability in the Primary Classroom," and "A Random Walk: Stumbling Across Connections."

A large number of Food and Drug Administration (FDA)-approved drugs have been found to inhibit the cell entry of Ebola virus (EBOV). However, since these drugs have various primary pharmacological targets, their mechanisms of action against EBOV remain largely unknown. We have previously shown that six FDA-approved drugs inhibit EBOV infection by interacting with and destabilizing the viral glycoprotein (GP). Here we show that antidepressants imipramine and clomipramine and antipsychotic drug thioridazine also directly interact with EBOV GP and determine the mode of interaction by crystallographic analysis of the complexes. The compounds bind within the same pocket as observed for other, chemically divergent complexes but with different binding modes. These details should be of value for the development of potent EBOV inhibitors. [ABSTRACT FROM AUTHOR]

Here, we show that four chemically divergent approved drugs reported to inhibit Ebolavirus infection, benztropine, bepridil, paroxetine and sertraline, directly interact with the Ebolavirus glycoprotein. Binding of these drugs destabilizes the protein, suggesting that this may be the mechanism of inhibition, as reported for the anticancer drug toremifene and the painkiller ibuprofen, which bind in the same large cavity on the glycoprotein. Crystal structures show that the position of binding and the mode of interaction within the pocket vary significantly between these compounds. The binding constants (Kd) determined by thermal shift assay correlate with the protein-inhibitor interactions as well as with the antiviral activities determined by virus cell entry assays, supporting the hypothesis that these drugs inhibit viral entry by binding the glycoprotein and destabilizing the prefusion conformation. Details of the protein-inhibitor interactions of these complexes and their relation with binding affinity may facilitate the design of more potent inhibitors. [ABSTRACT FROM AUTHOR]

We recently reported the existence of a physical interaction between the Myb-like transcription factor Dmp1 (Dmtf1) and p53 in which Dmp1 antagonized polyubiquitination of p53 by Mdm2 and promoted its nuclear localization. Dmp1 significantly stabilized p53-DNA complexes on promoters that contained p53-consensus sequences, which were either supershifted or disrupted with antibodies to Dmp1. Lysates from mice injected with doxorubicin showed that Dmp1 bound to p21Cip1, Bbc3, and Thbs1 gene regulatory regions in a p53-dependent fashion. Our data suggest that acceleration of DNA-binding of p53 by Dmp1 is a critical process for Dmp1 to increase the p53 function in Arf-deficient cells. [ABSTRACT FROM AUTHOR]

Echoviruses, for which there are currently no approved vaccines or drugs, are responsible for a range of human diseases, for example echovirus 11 (E11) is a major cause of serious neonatal morbidity and mortality. Decay-accelerating factor (DAF, also known as CD55) is an attachment receptor for E11. Here, we report the structure of the complex of E11 and the full-length ectodomain of DAF (short consensus repeats, SCRs, 1–4) at 3.1 Å determined by cryo-electron microscopy (cryo-EM). SCRs 3 and 4 of DAF interact with E11 at the southern rim of the canyon via the VP2 EF and VP3 BC loops. We also observe an unexpected interaction between the N-linked glycan (residue 95 of DAF) and the VP2 BC loop of E11. DAF is a receptor for at least 20 enteroviruses and we classify its binding patterns from reported DAF/virus complexes into two distinct positions and orientations, named as E6 and E11 poses. Whilst 60 DAF molecules can attach to the virion in the E6 pose, no more than 30 can attach to E11 due to steric restrictions. Analysis of the distinct modes of interaction and structure and sequence-based phylogenies suggests that the two modes evolved independently, with the E6 mode likely found earlier. [ABSTRACT FROM AUTHOR]

Strategies to prevent the recurrence of poliovirus (PV) after eradication may utilise non-infectious, recombinant virus-like particle (VLP) vaccines. Despite clear advantages over inactivated or attenuated virus vaccines, instability of VLPs can compromise their immunogenicity. Glutathione (GSH), an important cellular reducing agent, is a crucial co-factor for the morphogenesis of enteroviruses, including PV. We report cryo-EM structures of GSH bound to PV serotype 3 VLPs showing that it can enhance particle stability. GSH binds the positively charged pocket at the interprotomer interface shown recently to bind GSH in enterovirus F3 and putative antiviral benzene sulphonamide compounds in other enteroviruses. We show, using high-resolution cryo-EM, the binding of a benzene sulphonamide compound with a PV serotype 2 VLP, consistent with antiviral activity through over-stabilizing the interprotomer pocket, preventing the capsid rearrangements necessary for viral infection. Collectively, these results suggest GSH or an analogous tight-binding antiviral offers the potential for stabilizing VLP vaccines. Cryo-EM structures reveal the role of glutathione (GSH) in poliovirus (PV) serotype 3 virus-like particle (VLP) stability, suggesting GSH or an analogous tight-binding antiviral offers potential for stabilizing VLP vaccines against PV. [ABSTRACT FROM AUTHOR]

BA.2.87.1 represents a major shift in the BA.2 lineage of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is unusual in having two lengthy deletions of polypeptide in the spike (S) protein, one of which removes a beta-strand. Here we investigate its neutralization by a variety of sera from infected and vaccinated individuals and determine its spike (S) ectodomain structure. The BA.2.87.1 receptor binding domain (RBD) is structurally conserved and the RBDs are tightly packed in an "all-down" conformation with a small rotation relative to the trimer axis as compared to the closest previously observed conformation. The N-terminal domain (NTD) maintains a remarkably similar structure overall; however, the rearrangements resulting from the deletions essentially destroy the so-called supersite epitope and eliminate one glycan site, while a mutation creates an additional glycan site, effectively shielding another NTD epitope. BA.2.87.1 is relatively easily neutralized but acquisition of additional mutations in the RBD could increase antibody escape allowing it to become a dominant sub-lineage. [Display omitted] • The BA.2.87.1 RBD structure is conserved • Despite large deletions, the BA.2.87.1 NTD structure is similar overall • The NTD supersite epitope is destroyed and modifications to glycans alter others • BA.2.87.1 is relatively easily neutralized by sera from infected and vaccinated donors BA.2.87.1 is a SARS-CoV-2 variant with unusually large deletions in the surface spike N-terminal domain. Duyvesteyn et al. investigated its structure and found the main antibody binding "supersite" was destroyed and variations in glycan sites altered other epitopes. Despite these changes, BA.2.87.1 was relatively easily neutralized by sera from infected and vaccinated individuals. [ABSTRACT FROM AUTHOR]

Following the success of global vaccination programmes using the live-attenuated oral and inactivated poliovirus vaccines (OPV and IPV), wild poliovirus (PV) is now only endemic in Afghanistan and Pakistan. However, the continued use of these vaccines poses potential risks to the eradication of PV. The production of recombinant PV virus-like particles (VLPs), which lack the viral genome offer great potential as next-generation vaccines for the post-polio world. We have previously reported production of PV VLPs using Pichia pastoris, however, these VLPs were in the non-native conformation (C Ag), which would not produce effective protection against PV. Here, we build on this work and show that it is possible to produce wt PV-3 and thermally stabilised PV-3 (referred to as PV-3 SC8) VLPs in the native conformation (D Ag) using Pichia pastoris. We show that the PV-3 SC8 VLPs provide a much-improved D:C antigen ratio as compared to wt PV-3, whilst exhibiting greater thermostability than the current IPV vaccine. Finally, we determine the cryo-EM structure of the yeast-derived PV-3 SC8 VLPs and compare this to previously published PV-3 D Ag structures, highlighting the similarities between these recombinantly expressed VLPs and the infectious virus, further emphasising their potential as a next-generation vaccine candidate for PV [ABSTRACT FROM AUTHOR]

Although picornaviruses are conventionally considered 'nonenveloped', members of multiple picornaviral genera are released nonlytically from infected cells in extracellular vesicles. The mechanisms underlying this process are poorly understood. Here, we describe interactions of the hepatitis A virus (HAV) capsid with components of host endosomal sorting complexes required for transport (ESCRT) that play an essential role in release. We show release of quasi-enveloped virus (eHAV) in exosome-like vesicles requires a conserved export signal located within the 8 kDa C-terminal VP1 pX extension that functions in a manner analogous to late domains of canonical enveloped viruses. Fusing pX to a self-assembling engineered protein nanocage (EPN-pX) resulted in its ESCRT-dependent release in extracellular vesicles. Mutational analysis identified a 24 amino acid peptide sequence located within the center of pX that was both necessary and sufficient for nanocage release. Deleting a YxxL motif within this sequence ablated eHAV release, resulting in virus accumulating intracellularly. The pX export signal is conserved in non-human hepatoviruses from a wide range of mammalian species, and functional in pX sequences from bat hepatoviruses when fused to the nanocage protein, suggesting these viruses are released as quasi-enveloped virions. Quantitative proteomics identified multiple ESCRT-related proteins associating with EPN-pX, including ALG2-interacting protein X (ALIX), and its paralog, tyrosine-protein phosphatase non-receptor type 23 (HD-PTP), a second Bro1 domain protein linked to sorting of ubiquitylated cargo into multivesicular endosomes. RNAi-mediated depletion of either Bro1 domain protein impeded eHAV release. Super-resolution fluorescence microscopy demonstrated colocalization of viral capsids with endogenous ALIX and HD-PTP. Co-immunoprecipitation assays using biotin-tagged peptides and recombinant proteins revealed pX interacts directly through the export signal with N-terminal Bro1 domains of both HD-PTP and ALIX. Our study identifies an exceptionally potent viral export signal mediating extracellular release of virus-sized protein assemblies and shows release requires non-redundant activities of both HD-PTP and ALIX. Author summary: Mechanisms underlying nonlytic release of canonical nonenveloped viruses from infected cells are poorly understood. We show here that release of hepatitis A virus from cells in exosome-like vesicles requires nonredundant activities of two distinct Bro1-domain proteins associated with host cell machinery for endosomal sorting (ESCRT), HD-PTP and ALIX. We demonstrate both Bro1 domain proteins are recruited to the viral capsid by the pX segment of the 1D capsid protein, and that they act in a non-redundant manner to mediate virus release. Fusing pX to a self-assembling nanocage protein resulted in ESCRT-dependent release mediated by a short pX peptide sequence conserved in hepatoviruses from bats to humans. Mutations within the pX sequence ablate release and result in noncytolytic virus accumulating intracellularly. Our study identifies an exceptionally potent viral export signal mediating extracellular release of virus-sized protein assemblies and shows nonlytic release of quasi-enveloped virus is an ancient evolutionary trait of hepatoviruses. [ABSTRACT FROM AUTHOR]

Thed-Ala-d-Ala adding enzyme (MurF) from Streptococcus pneumoniae catalyzes the ATP-dependent formation of the UDP-MurNAc-pentapeptide, a critical component of the bacterial cell wall. MurF is a potential target for antibacterial design because it is unique to bacteria and performs an essential non-redundant function in the bacterial cell. The recent discovery and subsequent cocrystal structure determination of MurF in complex with a new class of inhibitors served as a catalyst to begin a medicinal chemistry program aimed at improving their potency. We report here a multidisciplinary approach to this effort that allowed for rapid generation of cocrystal structures, thereby providing the crystallographic information critical for driving the inhibitor optimization process. This effort resulted in the discovery of low-nanomolar inhibitors of this bacterial enzyme. [ABSTRACT FROM AUTHOR]

Field isolates of foot-and-mouth disease viruses (FMDVs) utilize integrin-mediated cell entry but many, including Southern African Territories (SAT) viruses, are difficult to adapt to BHK-21 cells, thus hampering large-scale propagation of vaccine antigen. However, FMDVs acquire the ability to bind to cell surface heparan sulphate proteoglycans, following serial cytolytic infections in cell culture, likely by the selection of rapidly replicating FMDV variants. In this study, fourteen SAT1 and SAT2 viruses, serially passaged in BHK-21 cells, were virulent in CHO-K1 cells and displayed enhanced affinity for heparan, as opposed to their low-passage counterparts. Comparative sequence analysis revealed the fixation of positively charged residues clustered close to the icosahedral 5-fold axes of the virus, at amino acid positions 83–85 in the βD-βE loop and 110–112 in the βF-βG loop of VP1 upon adaptation to cultured cells. Molecular docking simulations confirmed enhanced binding of heparan sulphate to a model of the adapted SAT1 virus, with the region around VP1 arginine 112 contributing the most to binding. Using this information, eight chimeric field strain mutant viruses were constructed with additional positive charges in repeated clusters on the virion surface. Five of these bound heparan sulphate with expanded cell tropism, which should facilitate large-scale propagation. However, only positively charged residues at position 110–112 of VP1 enhanced infectivity of BHK-21 cells. The symmetrical arrangement of even a single amino acid residue in the FMD virion is a powerful strategy enabling the virus to generate novel receptor binding and alternative host-cell interactions. Author summary: Foot-and-mouth disease (FMD) is a major threat for world economies. Local farmers in endemic areas relying on livestock for their livelihoods are affected by FMD outbreaks. Improved vaccines are essential for effective control and should be produced based on currently circulating field viruses. Current vaccines are produced by chemical inactivation of virus grown in large-scale production cultures of BHK-21 cells. However, not all field viruses can be adapted to cell cultures. The significance of our research is in identifying amino acid residues responsible for enhancing cell culture adaptation of FMD field viruses. This study engineered chimeric viruses containing the antigenic region of a field strain and novel cell culture receptor binding sites. This facilitated rapid virus amplification within a few passages in BHK-21 cells to create master virus seed stocks, circumventing the need for isolation on primary cell lines prior to further adaptation. [ABSTRACT FROM AUTHOR]

One of the first simulation-based introductory statistics curricula to be developed was the NSF-funded Change Agents for Teaching and Learning Statistics curriculum. True to its name, this curriculum is constantly undergoing change. This article describes the story of the curriculum as it has evolved at the University of Minnesota and offers insight into promising new future avenues for the curriculum to continue to affect radical, substantive change in the teaching and learning of statistics. for this article are available online. [ABSTRACT FROM AUTHOR]

Enteroviruses cause a range of human and animal diseases, some life-threatening, but there remain no licenced anti-enterovirus drugs. However, a benzene-sulfonamide derivative and related compounds have been shown recently to block infection of a range of enteroviruses by binding the capsid at a positively-charged surface depression conserved across many enteroviruses. It has also been established that glutathione is essential for the assembly of many enteroviruses, interacting with the capsid proteins to facilitate the formation of the pentameric assembly intermediate, although the mechanism is unknown. Here we show, by high resolution structure analyses of enterovirus F3, that reduced glutathione binds to the same interprotomer pocket as the benzene-sulfonamide derivative. Bound glutathione makes strong interactions with adjacent protomers, thereby explaining the underlying biological role of this druggable binding pocket and delineating the pharmacophore for potential antivirals. Helen Duyvesteyn et al. present a high-resolution structural analysis of gluthathione binding to an enterovirus capsid. They show that glutathione binds to a surface cavity, promoting assembly of the viral capsid, and providing a potential therapeutic target. [ABSTRACT FROM AUTHOR]