100 research outputs found

    Fine specificities of two lectins from Cymbosema roseum seeds: A lectin specific for high-mannose oligosaccharides and a lectin specific for blood group H type II trisaccharide

    Get PDF
    The legume species of Cymbosema roseum of Diocleinae subtribe produce at least two different seed lectins. The present study demonstrates that C. roseum lectin I (CRL I) binds with high affinity to the "core" trimannoside of N-linked oligosaccharides. Cymbosema roseum lectin II (CRL II), on the other hand, binds with high affinity to the blood group H trisaccharide (Fuc1,2Gal1-4GlcNAc-). Thermodynamic and hemagglutination inhibition studies reveal the fine binding specificities of the two lectins. Data obtained with a complete set of monodeoxy analogs of the core trimannoside indicate that CRL I recognizes the 3-, 4- and 6-hydroxyl groups of the (1,6) Man residue, the 3- and 4-hydroxyl group of the (1,3) Man residue and the 2- and 4-hydroxyl groups of the central Man residue of the trimannoside. CRL I possesses enhanced affinities for the Man5 oligomannose glycan and a biantennary complex glycan as well as glycoproteins containing high-mannose glycans. On the other hand, CRL II distinguishes the blood group H type II epitope from the Lewisx, Lewisy, Lewisa and Lewisb epitopes. CRL II also distinguishes between blood group H type II and type I trisaccharides. CRL I and CRL II, respectively, possess differences in fine specificities when compared with other reported mannose and fucose recognizing lectins. This is the first report of a mannose-specific lectin (CRL I) and a blood group H type II-specific lectin (CRL II) from seeds of a member of the Diocleinae subtribe. © 2011 The Author

    A warm Jupiter transiting an M dwarf: A TESS single transit event confirmed with the Habitable-zone Planet Finder

    Get PDF
    We confirm the planetary nature of a warm Jupiter transiting the early M dwarf TOI-1899, using a combination of available TESS photometry; high-precision, near-infrared spectroscopy with the Habitable-zone Planet Finder; and speckle and adaptive optics imaging. The data reveal a transiting companion on an 29\sim29-day orbit with a mass and radius of $0.66\pm0.07\ \mathrm{M_{J}}and and 1.15_{-0.05}^{+0.04}\ \mathrm{R_{J}},respectively.ThestarTOI1899isthelowestmassstarknowntohostatransitingwarmJupiter,andwediscussthefollowupopportunitiesaffordedbyawarm(, respectively. The star TOI-1899 is the lowest-mass star known to host a transiting warm Jupiter, and we discuss the follow-up opportunities afforded by a warm (\mathrm{T_{eq}}\sim362$ K) gas giant orbiting an M0 star. Our observations reveal that TOI-1899.01 is a puffy warm Jupiter, and we suggest additional transit observations to both refine the orbit and constrain the true dilution observed in TESS.Comment: 24 pages, 5 figures, 3 tables, published in A

    Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

    Get PDF
    Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

    Get PDF
    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

    Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

    Get PDF
    This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin

    Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

    Get PDF
    Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment

    Precise Masses in the WASP-47 System

    Get PDF
    We present precise radial velocity observations of WASP-47, a star known to host a hot Jupiter, a distant Jovian companion, and, uniquely, two additional transiting planets in short-period orbits: a super-Earth in a ~19 hour orbit, and a Neptune in a ~9 day orbit. We analyze our observations from the HARPS-N spectrograph along with previously published data to measure the most precise planet masses yet for this system. When combined with new stellar parameters and reanalyzed transit photometry, our mass measurements place strong constraints on the compositions of the two small planets. We find unlike most other ultra-short-period planets, the inner planet, WASP-47 e, has a mass (6.83 +/- 0.66 Me) and radius (1.810 +/- 0.027 Re) inconsistent with an Earth-like composition. Instead, WASP-47 e likely has a volatile-rich envelope surrounding an Earth-like core and mantle. We also perform a dynamical analysis to constrain the orbital inclination of WASP-47 c, the outer Jovian planet. This planet likely orbits close to the plane of the inner three planets, suggesting a quiet dynamical history for the system. Our dynamical constraints also imply that WASP-47 c is much more likely to transit than a geometric calculation would suggest. We calculate a transit probability for WASP-47 c of about 10%, more than an order of magnitude larger than the geometric transit probability of 0.6%.Comment: 15 pages, 3 figures, 3 tables. Accepted in A

    Global Systems-Level Analysis of Hfq and SmpB Deletion Mutants in Salmonella: Implications for Virulence and Global Protein Translation

    Get PDF
    Using sample-matched transcriptomics and proteomics measurements it is now possible to begin to understand the impact of post-transcriptional regulatory programs in Enterobacteria. In bacteria post-transcriptional regulation is mediated by relatively few identified RNA-binding protein factors including CsrA, Hfq and SmpB. A mutation in any one of these three genes, csrA, hfq, and smpB, in Salmonella is attenuated for mouse virulence and unable to survive in macrophages. CsrA has a clearly defined specificity based on binding to a specific mRNA sequence to inhibit translation. However, the proteins regulated by Hfq and SmpB are not as clearly defined. Previous work identified proteins regulated by hfq using purification of the RNA-protein complex with direct sequencing of the bound RNAs and found binding to a surprisingly large number of transcripts. In this report we have used global proteomics to directly identify proteins regulated by Hfq or SmpB by comparing protein abundance in the parent and isogenic hfq or smpB mutant. From these same samples we also prepared RNA for microarray analysis to determine if alteration of protein expression was mediated post-transcriptionally. Samples were analyzed from bacteria grown under four different conditions; two laboratory conditions and two that are thought to mimic the intracellular environment. We show that mutants of hfq and smpB directly or indirectly modulate at least 20% and 4% of all possible Salmonella proteins, respectively, with limited correlation between transcription and protein expression. These proteins represent a broad spectrum of Salmonella proteins required for many biological processes including host cell invasion, motility, central metabolism, LPS biosynthesis, two-component regulatory systems, and fatty acid metabolism. Our results represent one of the first global analyses of post-transcriptional regulons in any organism and suggest that regulation at the translational level is widespread and plays an important role in virulence regulation and environmental adaptation for Salmonella

    A whisper-game perspective on the family communication of DNA-test results: a retrospective study on the communication process of BRCA1/2-test results between proband and relatives

    Get PDF
    Objective of this paper is to study how DNA-test result information was communicated and perceived within families. A retrospective descriptive study in 13 probands with a BRCA1/2 unclassified variant, 7 with a pathogenic mutation, 5 with an uninformative result, and in 44, 14, and 12 of their 1st and 2nd degree relatives respectively. We examined differences and correlations between: (a) information actually communicated (b) probands' perception, (c) relatives' perception. The perception consisted of recollections and interpretations of both their own and their relatives' cancer-risks, and heredity-likelihood (i.e. likelihood that cancer is heritable in the family). Differences and low correlations suggested few similarities between the actually communicated information, the probands' and the relatives' perception. More specifically, probands recalled the communicated information differently compared with the actually communicated information (R = .40), and reinterpreted this information differently (R = .30). The relatives' perception was best correlated with the proband's interpretation (R = .08), but this perception differed significantly from their proband's perception. Finally, relatives reinterpreted the information they received from their proband differently (R = .25), and this interpretation was only slightly related with the original message communicated by the genetic-counsellor (R = .15). Unclassified-variants were most frequently misinterpreted by probands and relatives, and had the largest differences between probands' and relatives' perceptions. Like in a children's whisper-game, many errors occur in the transmission of DNA-test result information in families. More attention is required for how probands disseminate information to relatives. Genetic-counsellors may help by supporting the probands in communicating to relatives, e.g. by providing clear summary letters for relatives

    The Cancer Genome Atlas Comprehensive Molecular Characterization of Renal Cell Carcinoma

    Get PDF
    corecore