Structural Biology and Its Role in Variant Classification

Total Page:16

File Type:pdf, Size:1020Kb

Structural Biology and Its Role in Variant Classification Structural biology and its role in variant classification Created for educational purposes by Iain Kerr, Ph.D. Medical Services, Myriad Genetic Laboratories, Inc. Data presented as of June 2016 Myriad and the Myriad logo are registered trademarks of Myriad Genetics, Inc., in the United States and other jurisdictions. ©2016 Myriad Genetic Laboratories, Inc. Introduction/Background Structural Biology is the study of the three-dimensional structure of proteins and nucle- ic acids and their interaction with other molecules in the cell. As the structure of these molecules is associated with their function,1-6 mutations that impart structural changes may lead to the production of abnormal/malfunctioning proteins that cause disease. transcription translation DNA RNA protein The basis of the central dogma and the foundation of genetic testing lies in the discovery of the double-helical structure of DNA, which revealed the molecular details of the genetic code and implied a copying mechanism that would later be replicated in vitro to perform DNA sequencing.7, 8 MEEPQSDPSVEPPLSQETFSDLWKLLPENN A B VLSPLPSQAMDDLMLSPDDIEQWFTEDPGP DEAPRMPEAAPPVAPAPAAPTPAAPAPAPS unfolded protein chain Folded protein Figure 1. Linear strings of amino acids form a folded, three dimensional protein. (A) Part of the p53 amino acid sequence (above). (below) Individual blocks in the schematic represent indvidual amino acids, like beads on a string (B) The three dimensional structure of the DNA-binding domain of TP53 bound to DNA. Created for educational purposes by Medical Services, Myriad Genetics Laboratories. Data presented as of June 2016. 2 A B C MSH2 MSH6 Figure 2. Protein domain structure and organization. (A) the ATPase domain of MSH2. (B) The full-length MSH2 protein. Individual domains differ in color. The ATPase domain is circled (C) The structure of the MSH2•MSH6 mismatch recognition complex. During protein synthesis, as the primary amino acid sequence is converted into more complex structure, separate protein domains begin to form (Fig. 2A). Domains represent conserved, independently folded modules of a protein that have their own compact, structure. Protein domains often have unique functions that are essential to the role played by the protein in the cell. A protein may contain one domain (Fig. 2A) or multiple domains (Fig. 2B). Often, two or more proteins interact to form a functional complex (Fig. 2C), as is often the case during DNA repair. For this reason, conservation analysis of the primary sequence is insufficient to explain the role of a variant and may be thought of as one-dimensional solution to a more complex, multi-component, three-dimensional problem. Created for educational purposes by Medical Services, Myriad Genetics Laboratories. Data presented as of June 2016. 3 Techniques While Structural Biology encompasses a number of experimental techniques, Nuclear Magnetic Resonance Spectrospcopy (NMR) and X-ray Crystallography produce the most accurate, detailed protein structures. X-ray Crystallography is routinely used by the pharmaceutical industry in rational drug-design9-12 and is the primary method of choice for full structure determination. NMR has the advantage of being able to study the dynamics of a protein (how proteins ‘move’). However, the NMR experiment is limited by the size of protein that can be studied in solution. Many of the commonly studied hereditary cancer genes encode large proteins outside the reach of NMR. Figure 3. Three stages of the X-ray crystallography experiment – crystal growth, diffraction image from a protein crystal exposed to X-rays and the final structure In cases where experimental structure data are not available for a given protein, homology modelling may be used when the structure of a protein, similar to the desired target, is known. As the precision of the homology model cannot be validated against experimental structure data, great care must be taken when using this method. To ensure the accuracy of the model, the target protein and the homolog with known structure should have amino acid sequences that share a high degree of identity. 13, 14 More advanced computational techniques may be used to further explore the effect a given variant may have on protein structure and function.15 These methods are especially useful in X-ray crystal structure analysis; while proteins and their atoms are known to exhibit dynamic motion, crystal structures represent a ‘static’, averaged, snap-shot in time. Techniques such as Molecular Dynamics (MD), can provide information on the motion of surrounding structure when a variant is introduced, or on the protein as a whole. In recognition of the importance of this field, Drs. Martin Karplus, Michael Levitt and Arieh Warshel received the 2013 Nobel Prize in Chemistry for “the development of multiscale models for complex chemical systems.” Created for educational purposes by Medical Services, Myriad Genetics Laboratories. Data presented as of June 2016. 4 Structural Biology in Variant Classification The 2015 ACMG “Standards and guidelines for the interpretation of sequence variants”16 state that mutations located within a “critical and well-established functional domain” may be considered moderate evidence of pathogenicity. This provides a platform for the use of Structural Biology in variant classification. In particular, this method is advantageous for missense variants where current non-structural data, in isolation, are insufficient to lead to a definitive classification. Case 1. TP53 c.844C>T (p.Arg282Trp) DNA L1 Arg282 (wild-type) DNA L1 ? Arg282Trp (variant) Figure 4. A three-dimensional structure of the TP53 tetramer bound to DNA. The small square denotes the region where the variant occurs on one p53 molecule. Large squares show this region in greater detail. Created for educational purposes by Medical Services, Myriad Genetics Laboratories. Data presented as of June 2016. 5 The variant is located in the DNA-binding domain (DBD) of TP53. In addition, Arg282 is a mutation ‘hotspot’ for TP53 pathogenic mutations. For this variant, an experimentally determined structure is available.17 This is often not the case and protein modelling of the wild-type structure is usually required to visualize the effect of most variants. The substitution of arginine (Arg) for tryptophan (Trp) at amino acid 282 causes displacement of the DNA-binding L1 loop and the surrounding structure becomes more flexible, showing this to be a destabilizing mutation. When analyzed at 37˚C in a biophysical assay, the mutation is show to completely unfold the TP53 protein18, confirming the structural mechanism. Unfolded proteins like TP53 are unable to perform their function. Given the evidence, this mutation is classified as suspected deleterious (likely pathogenic). Case 2. BRCA1 c.5153G>C (p.Trp1718Ser) Trp1718 (wild-type) BRCT1 BRCT2 Figure 5. A three-dimensional structure of the BRCT domains of BRCA1. The variant is buried in the BRCT1 domain of BRCA1. Trp1718Ser Created for educational purposes by Medical Services, Myriad Genetics Laboratories. Data presented as of June 2016. 6 The ability of the C-terminal BRCT domains to bind phosphorylated proteins is essential to BRCA1’s role as a tumour suppressor. 19 Trp1718 is buried in the core of the BRCT1 domain. Mutations buried in the protein core are frequently associated with disease.20 The variant, Trp1718Ser, has a much smaller side chain creating a cavity in the protein core. Cavity creating mutations are known to be destabilizing to protein structure. In vitro, biochemical analysis of Trp1718Ser by Lee et al. confirmed that the mutant protein harbors a severe folding defect which compromises the downstream activity of BRCA1.21 On the basis of structural analysis and functional data, c.5153G>C (p.Trp1718Ser) is therefore considered suspected deleterious. References [1] Phillips, D. C. (1966) The three-dimensional structure of an enzyme molecule, Scientific American 215, 78-90. [2] Edelman, G. M. (1973) Antibody structure and molecular immunology, Science 180, 830-840. [3] Martin, A. C., Orengo, C. A., Hutchinson, E. G., Jones, S., Karmirantzou, M., Laskowski, R. A., Mitchell, J. B., Taroni, C., and Thornton, J. M. (1998) Protein folds and functions, Structure 6, 875-884. [4] Hegyi, H., and Gerstein, M. (1999) The relationship between protein structure and function: a comprehensive survey with application to the yeast genome, Journal of molecular biology 288, 147-164. [5] Thornton, J. M., Orengo, C. A., Todd, A. E., and Pearl, F. M. (1999) Protein folds, functions and evolution, Journal of molecular biology 293, 333-342. [6] Dessailly, B. H., Redfern, O. C., Cuff, A., and Orengo, C. A. (2009) Exploiting structural classifications for function prediction: towards a domain grammar for protein function, Current opinion in structural biology 19, 349-356. [7] Watson, J. D., and Crick, F. H. (1953) Molecular structure of nucleic acids; a structure for deoxyribose nucleic acid, Nature 171, 737-738. [8] Watson, J. D., and Crick, F. H. (1953) Genetical implications of the structure of deoxyribonucleic acid, Nature 171, 964-967. [9] Colman, P. M. (1994) Structure-based drug design, Current opinion in structural biology 4, 868-874. [10] Wlodawer, A., and Vondrasek, J. (1998) Inhibitors of HIV-1 protease: a major success of structure-assisted drug design, Annual review of biophysics and biomolecular structure 27, 249-284. [11] Chen, L., Morrow, J. K., Tran, H. T., Phatak, S. S., Du-Cuny, L., and Zhang, S. (2012) From laptop to benchtop to bedside: structure-based drug design on protein targets, Current pharmaceutical design 18, 1217-1239. [12] Congreve, M., Dias, J. M., and Marshall, F. H. (2014) Structure-based drug design for G protein-coupled receptors, Progress in medicinal chemistry 53, 1-63. [13] Dalton, J. A., and Jackson, R. M. (2007) An evaluation of automated homology modelling methods at low target template sequence similarity, Bioinformatics 23, 1901-1908. [14] Kopp, J., and Schwede, T. (2004) Automated protein structure homology modeling: a progress report, Pharmacogenomics 5, 405-416. [15] Friedman, R., Boye, K., and Flatmark, K. (2013) Molecular modelling and simulations in cancer research, Biochimica et biophysica acta 1836, 1-14.
Recommended publications
  • Structural Data in Synthetic Biology Approaches for Studying General Design Principles of Cellular Signaling Networks
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Structure Perspective Structural Data in Synthetic Biology Approaches for Studying General Design Principles of Cellular Signaling Networks Christina Kiel1,2,* and Luis Serrano1,2,3 1EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain 2Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain 3ICREA, Pg. Lluı´s Companys 23, 08010 Barcelona, Spain *Correspondence: [email protected] http://dx.doi.org/10.1016/j.str.2012.10.002 In recent years, high-throughput discovery of macromolecular protein structures and complexes has played a major role in advancing a more systems-oriented view of protein interaction and signaling networks. The design of biological systems often employs structural information or structure-based protein design to successfully implement synthetic signaling circuits or for rewiring signaling flows. Here, we summarize the latest advances in using structural information for studying protein interaction and signaling networks, and in synthetic biology approaches. We then provide a perspective of how combining structural biology with engineered cell signaling modules—using additional information from quantitative biochemistry and proteo- mics, gene evolution, and mathematical modeling—can provide insight into signaling modules and the general design principles of cell signaling. Ultimately, this will improve our understanding of cell- and tissue-type-specific signal transduction. Integrating the quantitative effects of disease mutations into these systems may provide a basis for elucidating the molecular mechanisms of diseases. Introduction further complicated by the fact that often proteins recruit binding There is growing three-dimensional (3D) structural information partners using several domain or linear motifs.
    [Show full text]
  • The Architecture of the Protein Domain Universe
    The architecture of the protein domain universe Nikolay V. Dokholyan Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC 27599 ABSTRACT Understanding the design of the universe of protein structures may provide insights into protein evolution. We study the architecture of the protein domain universe, which has been found to poses peculiar scale-free properties (Dokholyan et al., Proc. Natl. Acad. Sci. USA 99: 14132-14136 (2002)). We examine the origin of these scale-free properties of the graph of protein domain structures (PDUG) and determine that that the PDUG is not modular, i.e. it does not consist of modules with uniform properties. Instead, we find the PDUG to be self-similar at all scales. We further characterize the PDUG architecture by studying the properties of the hub nodes that are responsible for the scale-free connectivity of the PDUG. We introduce a measure of the betweenness centrality of protein domains in the PDUG and find a power-law distribution of the betweenness centrality values. The scale-free distribution of hubs in the protein universe suggests that a set of specific statistical mechanics models, such as the self-organized criticality model, can potentially identify the principal driving forces of molecular evolution. We also find a gatekeeper protein domain, removal of which partitions the largest cluster into two large sub- clusters. We suggest that the loss of such gatekeeper protein domains in the course of evolution is responsible for the creation of new fold families. INTRODUCTION The principles of molecular evolution remain elusive despite fundamental breakthroughs on the theoretical front 1-5 and a growing amount of genomic and proteomic data, over 23,000 solved protein structures 6 and protein functional annotations 7-9.
    [Show full text]
  • Synthetic Biology Applying Engineering to Biology
    Synthetic Biology Applying Engineering to Biology Report of a NEST High-Level Expert Group EUR 21796 PROJECT REPORT Interested in European research? RTD info is our quarterly magazine keeping you in touch with main developments (results, programmes, events, etc). It is available in English, French and German. A free sample copy or free subscription can be obtained from: European Commission Directorate-General for Research Information and Communication Unit B-1049 Brussels Fax : (32-2) 29-58220 E-mail: [email protected] Internet: http://europa.eu.int/comm/research/rtdinfo/index_en.html EUROPEAN COMMISSION Directorate-General for Research Directorate B — Structuring the European Research Area Unit B1 — Anticipation of Scientific and Technological Needs (NEST activity); Basic Research E-mail: [email protected] Contact: Christian Krassnig European Commission Office SDME 01/37 B-1049 Brussels Tel. (32-2) 29-86445 Fax (32-2) 29-93173 E-mail: [email protected] For further information on the NEST activity please refer to the following website: http://www.cordis.lu/nest/home.html EUROPEAN COMMISSION Synthetic Biology Applying Engineering to Biology Report of a NEST High-Level Expert Group NEST - New and Energing Science and Technology - is a research activity under the European Community’s 6th Framework Programme Directorate-General for Research Structuring the European Research Area 2005 Anticipating Scientific and Technological Needs; Basic Research EUR 21796 Europe Direct is a service to help you find answers to your questions about the European Union Freephone number: 00 800 6 7 8 9 10 11 LEGAL NOTICE: Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use which might be made of the following information.
    [Show full text]
  • Biochemistry Biotechnology Cell Biology
    Undergraduate Biochemistry Opportunities www.ed.ac.uk/biology Biotechnology Cell Biology Biochem_Biotech_CellBio_A5.indd 1 21/05/2019 14:25 Biochemistry The programme combines coverage of the Biochemistry is the study of living systems at basic principles and knowledge underpinning the cellular and molecular level. This dynamic biotechnology and an appreciation of the field draws on a variety of subjects and has processes involved in converting an idea widespread application. Biochemistry applies a into a product. The objective is to provide a knowledge of chemistry and physical sciences firm foundation in molecular and microbial to investigate basic life processes. The subject biotechnology through compulsory sections has a major impact on modern medical research dealing with topics such as expression vectors, and upon the pharmaceutical, bioengineering, microbial fermentation, protein structure, drug agricultural and environmental industries. design and the development of antimicrobials and vaccines. The programme encourages the critical assessment of current developments in areas of Cell Biology biological interest. Modern cell biology is a dynamic discipline that combines the interests and techniques of many Biotechnology scientific fields. Cell biologists investigate the Biotechnology is concerned with industrial basic structural and functional units of life, the and biomedical applications of fundamental cells that compose all living organisms. They aim knowledge derived from biology. This covers to understand: cellular structure, composition many facets from making useful products and regulation, the organelles that cells contain, using microbial, plant or animal cells to using cell growth, nuclear and cellular division, and bioinformatics and structural biology to design cell death. Understanding how cells work is new drugs. Biotechnology is an exciting area fundamental to many areas of biology and is of with new developments each year in areas that particular importance to fields such as cancer affect us all.
    [Show full text]
  • Cmse 520 Biomolecular Structure, Function And
    CMSE 520 BIOMOLECULAR STRUCTURE, FUNCTION AND DYNAMICS (Computational Structural Biology) OUTLINE Review: Molecular biology Proteins: structure, conformation and function(5 lectures) Generalized coordinates, Phi, psi angles, DNA/RNA: structure and function (3 lectures) Structural and functional databases (PDB, SCOP, CATH, Functional domain database, gene ontology) Use scripting languages (e.g. python) to cross refernce between these databases: starting from sequence to find the function Relationship between sequence, structure and function Molecular Modeling, homology modeling Conservation, CONSURF Relationship between function and dynamics Confromational changes in proteins (structural changes due to ligation, hinge motions, allosteric changes in proteins and consecutive function change) Molecular Dynamics Monte Carlo Protein-protein interaction: recognition, structural matching, docking PPI databases: DIP, BIND, MINT, etc... References: CURRENT PROTOCOLS IN BIOINFORMATICS (e-book) (http://www.mrw.interscience.wiley.com/cp/cpbi/articles/bi0101/frame.html) Andreas D. Baxevanis, Daniel B. Davison, Roderic D.M. Page, Gregory A. Petsko, Lincoln D. Stein, and Gary D. Stormo (eds.) 2003 John Wiley & Sons, Inc. INTRODUCTION TO PROTEIN STRUCTURE Branden C & Tooze, 2nd ed. 1999, Garland Publishing COMPUTER SIMULATION OF BIOMOLECULAR SYSTEMS Van Gusteren, Weiner, Wilkinson Internet sources Ref: Department of Energy Rapid growth in experimental technologies Human Genome Projects Two major goals 1. DNA mapping 2. DNA sequencing Rapid growth in experimental technologies z Microrarray technologies – serial gene expression patterns and mutations z Time-resolved optical, rapid mixing techniques - folding & function mechanisms (Æ ns) z Techniques for probing single molecule mechanics (AFM, STM) (Æ pN) Æ more accurate models/data for computer-aided studies Weiss, S. (1999). Fluorescence spectroscopy of single molecules.
    [Show full text]
  • BCH 6746: Structural Biology Course Prerequisites: CRN 12063 Section 001, 3 Credit Hours
    Please note: Each college and department may have their own requirements, in addition to those stated in the Syllabus Guidelines. BCH 6746: Structural Biology Course Prerequisites: CRN 12063 Section 001, 3 Credit hours College of Arts and Sciences, CMMB COURSE SYLLABUS Insert USF Logo here Instructor Name: Yu Chen Semester/Term & Year: Spring 2019 Class Meeting Days: TR Class Meeting Time: 11:00 – 12:20 pm Class Meeting Location: MDC 1507 Lab Meeting Location: N/A Delivery Method: Lecture I. Welcome! II. University Course Description The theory and application of modern physical biochemical techniques. III. Course Objectives This course focuses on relating theoretical concepts and experimental approaches to a wide range of potential research problems in the area of structural biology. The course aims to provide a solid foundation and breadth of understanding in structural biology that will facilitate application to current and future research problems. IV. Course Purpose Major Topics: Introduction to Structural Biology; From Structure to Function I; From Structure to Function II; From Structure to Function III; From Structure fo Function IV; Control of Protein Function I; Strategies for Protein Separation; Strategies for Protein Identification; Chemical and Immunochemical Probes of Structure; Methods in Structural Bio I, II, II; Structure Determination I, II, III, IV; Control of Protein Function II, III, IV V. Learning Outcomes Students will gain an understanding of the basic science of Protein Structure, including first principles of the physical interactions that maintain proteins and the mechanisms that make them tic. They will also learn about different techniques and experimental approaches that represent the state-of-the-art and are widely used in the study of proteins.
    [Show full text]
  • MATHEMATICAL TECHNIQUES in STRUCTURAL BIOLOGY Contents 0. Introduction 4 1. Molecular Genetics: DNA 6 1.1. Genetic Code 6 1.2. T
    MATHEMATICAL TECHNIQUES IN STRUCTURAL BIOLOGY J. R. QUINE Contents 0. Introduction 4 1. Molecular Genetics: DNA 6 1.1. Genetic code 6 1.2. The geometry of DNA 6 1.3. The double helix 6 1.4. Larger organization of DNA 7 1.5. DNA and proteins 7 1.6. Problems 7 2. Molecular Genetics: Proteins 10 2.1. Amino Acids 10 2.2. The genetic code 10 2.3. Amino acid template 11 2.4. Tetrahedral geometry 11 2.5. Amino acid structure 13 2.6. The peptide bond 13 2.7. Protein structure 14 2.8. Secondary structure 14 3. Frames and moving frames 19 3.1. Basic definitions 19 3.2. Frames and gram matrices 19 3.3. Frames and rotations 20 3.4. Frames fixed at a point 20 3.5. The Frenet Frame 20 3.6. The coiled-coil 22 3.7. The Frenet formula 22 3.8. Problems 24 4. Orthogonal transformations and Rotations 25 4.1. The rotation group 25 4.2. Complex form of a rotation 28 4.3. Eigenvalues of a rotation 28 4.4. Properties of rotations 29 4.5. Problems 30 5. Torsion angles and pdb files 33 5.1. Torsion Angles 33 5.2. The arg function 34 5.3. The torsion angle formula 34 5.4. Protein torsion angles. 35 5.5. Protein Data Bank files. 35 1 2 J. R. QUINE 5.6. Ramachandran diagram 36 5.7. Torsion angles on the diamond packing 37 5.8. Appendix, properties of cross product 38 5.9. Problems 38 6.
    [Show full text]
  • Action of Multiple Rice -Glucosidases on Abscisic Acid Glucose Ester
    International Journal of Molecular Sciences Article Action of Multiple Rice β-Glucosidases on Abscisic Acid Glucose Ester Manatchanok Kongdin 1, Bancha Mahong 2, Sang-Kyu Lee 2, Su-Hyeon Shim 2, Jong-Seong Jeon 2,* and James R. Ketudat Cairns 1,* 1 School of Chemistry, Institute of Science, Center for Biomolecular Structure, Function and Application, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand; [email protected] 2 Graduate School of Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin 17104, Korea; [email protected] (B.M.); [email protected] (S.-K.L.); [email protected] (S.-H.S.) * Correspondence: [email protected] (J.-S.J.); [email protected] (J.R.K.C.); Tel.: +82-31-2012025 (J.-S.J.); +66-44-224304 (J.R.K.C.); Fax: +66-44-224185 (J.R.K.C.) Abstract: Conjugation of phytohormones with glucose is a means of modulating their activities, which can be rapidly reversed by the action of β-glucosidases. Evaluation of previously characterized recombinant rice β-glucosidases found that nearly all could hydrolyze abscisic acid glucose ester (ABA-GE). Os4BGlu12 and Os4BGlu13, which are known to act on other phytohormones, had the highest activity. We expressed Os4BGlu12, Os4BGlu13 and other members of a highly similar rice chromosome 4 gene cluster (Os4BGlu9, Os4BGlu10 and Os4BGlu11) in transgenic Arabidopsis. Extracts of transgenic lines expressing each of the five genes had higher β-glucosidase activities on ABA-GE and gibberellin A4 glucose ester (GA4-GE). The β-glucosidase expression lines exhibited longer root and shoot lengths than control plants in response to salt and drought stress.
    [Show full text]
  • Evolution of Biomolecular Structure Class II Trna-Synthetases and Trna
    University of Illinois at Urbana-Champaign Luthey-Schulten Group Theoretical and Computational Biophysics Group Evolution of Biomolecular Structure Class II tRNA-Synthetases and tRNA MultiSeq Developers: Prof. Zan Luthey-Schulten Elijah Roberts Patrick O’Donoghue John Eargle Anurag Sethi Dan Wright Brijeet Dhaliwal March 2006. A current version of this tutorial is available at http://www.ks.uiuc.edu/Training/Tutorials/ CONTENTS 2 Contents 1 Introduction 4 1.1 The MultiSeq Bioinformatic Analysis Environment . 4 1.2 Aminoacyl-tRNA Synthetases: Role in translation . 4 1.3 Getting Started . 7 1.3.1 Requirements . 7 1.3.2 Copying the tutorial files . 7 1.3.3 Configuring MultiSeq . 8 1.3.4 Configuring BLAST for MultiSeq . 10 1.4 The Aspartyl-tRNA Synthetase/tRNA Complex . 12 1.4.1 Loading the structure into MultiSeq . 12 1.4.2 Selecting and highlighting residues . 13 1.4.3 Domain organization of the synthetase . 14 1.4.4 Nearest neighbor contacts . 14 2 Evolutionary Analysis of AARS Structures 17 2.1 Loading Molecules . 17 2.2 Multiple Structure Alignments . 18 2.3 Structural Conservation Measure: Qres . 19 2.4 Structure Based Phylogenetic Analysis . 21 2.4.1 Limitations of sequence data . 21 2.4.2 Structural metrics look further back in time . 23 3 Complete Evolutionary Profile of AspRS 26 3.1 BLASTing Sequence Databases . 26 3.1.1 Importing the archaeal sequences . 26 3.1.2 Now the other domains of life . 27 3.2 Organizing Your Data . 28 3.3 Finding a Structural Domain in a Sequence . 29 3.4 Aligning to a Structural Profile using ClustalW .
    [Show full text]
  • The Effect of Dicer Knockout on RNA Interference Using Various Dicer Substrate Interfering RNA Structures
    bioRxiv preprint doi: https://doi.org/10.1101/2020.04.19.049817; this version posted April 20, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. The effect of Dicer knockout on RNA interference using various Dicer substrate interfering RNA structures Min-Sun Song1 and John J Rossi1, 2 * 1Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, City of Hope, Duarte, CA 91010, USA 2Irell and Manella Graduate School of Biological Sciences, Beckman Research Institute of City of Hope, City of Hope, Duarte, CA 91010, USA *Corresponding author: John J. Rossi, Email address: [email protected]. Running title: Dicer regulation of DsiRNAs Keywords: Dicer, tetra-loop, Dicer-substrate siRNA(DsiRNA), RNA interference(RNAi), RNA biogenesis, Dicer knockout 1 bioRxiv preprint doi: https://doi.org/10.1101/2020.04.19.049817; this version posted April 20, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Abstract Dicer-substrate siRNA (DsiRNA) was a useful tool for sequence-specific gene silencing. DsiRNA was proposed to have increased efficacy via RNAi gene silencing, but the molecular mechanism underlying the increased efficacy is not precise. We designed the tetra-looped DsiRNA as the tetra-looped RNAs have been reported more stable structure and increased binding efficiency with RNA and protein.
    [Show full text]
  • The Institute of Botany
    FEATURE ARTICLE Taiwan’s Academia Sinica Forges Ahead Research in the life sciences has expanded and improved, and is conforming to international standards institutes and research projects, to promote academic collaboration between Taiwan and other countries, and to make plans for academic development when requested by the government. It is also responsible for nominating three candidates for the presidency when the president vacates, as well as formulation of rules pertaining to the Academia. The Central Advisory Committee consists of chairpersons of the advisory committee of the individual institutes, and two to three specialists from each of the Academia’s three divisions. One of the vice presidents of the Academia serves as its chairperson. The committee recruits national and international specialists for the Academia and also creates long-term interdisciplinary research plans. It is also he development of science and 188 associate research fellows, 134 responsible for evaluating and promoting T technology has been given much assistant research fellows, 123 assistant inter-institutional large-scale research importance by the Taiwan government in fellows, and 20 research assistants. projects, evaluating applications of recent years. This can be seen from the postdoctoral researchers, and selecting Organization increased expenditure on science and winners for the Academia’s annual technology, and the annual increase in The Academia is headed by Dr. Yuan- awards for outstanding publications by national R&D budget. The government Tseh Lee, its president. Dr. Lee is the junior research faculties. is determined to improve the quality of 1986 Nobel Laureate in Chemistry. He Division of Life Sciences research carried out in the country.
    [Show full text]
  • Journal of Molecular Biology
    JOURNAL OF MOLECULAR BIOLOGY AUTHOR INFORMATION PACK TABLE OF CONTENTS XXX . • Description p.1 • Audience p.2 • Impact Factor p.2 • Abstracting and Indexing p.2 • Editorial Board p.2 • Guide for Authors p.6 ISSN: 0022-2836 DESCRIPTION . Journal of Molecular Biology (JMB) provides high quality, comprehensive and broad coverage in all areas of molecular biology. The journal publishes original scientific research papers that provide mechanistic and functional insights and report a significant advance to the field. The journal encourages the submission of multidisciplinary studies that use complementary experimental and computational approaches to address challenging biological questions. Research areas include but are not limited to: Biomolecular interactions, signaling networks, systems biology Cell cycle, cell growth, cell differentiation Cell death, autophagy Cell signaling and regulation Chemical biology Computational biology, in combination with experimental studies DNA replication, repair, and recombination Development, regenerative biology, mechanistic and functional studies of stem cells Epigenetics, chromatin structure and function Gene expression Receptors, channels, and transporters Membrane processes Cell surface proteins and cell adhesion Methodological advances, both experimental and theoretical, including databases Microbiology, virology, and interactions with the host or environment Microbiota mechanistic and functional studies Nuclear organization Post-translational modifications, proteomics Processing and function of biologically
    [Show full text]