Motto: Representing Motifs in Consensus Sequences with Minimum Information Loss
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DNA Sequencing and Sorting: Identifying Genetic Variations
BioMath DNA Sequencing and Sorting: Identifying Genetic Variations Student Edition Funded by the National Science Foundation, Proposal No. ESI-06-28091 This material was prepared with the support of the National Science Foundation. However, any opinions, findings, conclusions, and/or recommendations herein are those of the authors and do not necessarily reflect the views of the NSF. At the time of publishing, all included URLs were checked and active. We make every effort to make sure all links stay active, but we cannot make any guaranties that they will remain so. If you find a URL that is inactive, please inform us at [email protected]. DIMACS Published by COMAP, Inc. in conjunction with DIMACS, Rutgers University. ©2015 COMAP, Inc. Printed in the U.S.A. COMAP, Inc. 175 Middlesex Turnpike, Suite 3B Bedford, MA 01730 www.comap.com ISBN: 1 933223 71 5 Front Cover Photograph: EPA GULF BREEZE LABORATORY, PATHO-BIOLOGY LAB. LINDA SHARP ASSISTANT This work is in the public domain in the United States because it is a work prepared by an officer or employee of the United States Government as part of that person’s official duties. DNA Sequencing and Sorting: Identifying Genetic Variations Overview Each of the cells in your body contains a copy of your genetic inheritance, your DNA which has been passed down to you, one half from your biological mother and one half from your biological father. This DNA determines physical features, like eye color and hair color, and can determine susceptibility to medical conditions like hypertension, heart disease, diabetes, and cancer. -
Regulatory Motifs of DNA
Lecture 3: PWMs and other models for regulatory elements in DNA -Sequence motifs -Position weight matrices (PWMs) -Learning PWMs combinatorially, or probabilistically -Learning from an alignment -Ab initio learning: Baum-Welch & Gibbs sampling -Visualization of PWMs as sequence logos -Search methods for PWM occurrences -Cis-regulatory modules Regulatory motifs of DNA Measuring gene activity (’expression’) with a microarray 1 Jointly regulated gene sets Cluster of co-expressed genes, apply pattern discovery in regulatory regions 600 basepairs Expression profiles Retrieve Upstream regions Genes with similar expression pattern Pattern over-represented in cluster Find a hidden motif 2 Find a hidden motif Find a hidden motif (cont.) Multiple local alignment! Smith-Waterman?? 3 Motif? • Definition: Motif is a pattern that occurs (unexpectedly) often in a string or in a set of strings • The problem of finding repetitions is similar cgccgagtgacagagacgctaatcagg ctgtgttctcaggatgcgtaccgagtg ggagacagcagcacgaccagcggtggc agagacccttgcagacatcaagctctt tgggaacaagtggagcaccgatgatgt acagccgatcaatgacatttccctaat gcaggattacattgcagtgcccaagga gaagtatgccaagtaatacctccctca cagtg... 4 Longest repeat? Example: A 50 million bases long fragment of human genome. We found (using a suffix-tree) the following repetitive sequence of length 2559, with one occurrence at 28395980, and other at 28401554r ttagggtacatgtgcacaacgtgcaggtttgttacatatgtatacacgtgccatgatggtgtgctgcacccattaactcgtcatttagcgttaggtatatctcc gaatgctatccctcccccctccccccaccccacaacagtccccggtgtgtgatgttccccttcctgtgtccatgtgttctcattgttcaattcccacctatgagt -
Motif Discovery in Sequential Data Kyle L. Jensen
Motif discovery in sequential data by Kyle L. Jensen Submitted to the Department of Chemical Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY May © Kyle L. Jensen, . Author.............................................................. Department of Chemical Engineering April , Certified by . Gregory N. Stephanopoulos Bayer Professor of Chemical Engineering esis Supervisor Accepted by . William M. Deen Chairman, Department Committee on Graduate Students Motif discovery in sequential data by Kyle L. Jensen Submitted to the Department of Chemical Engineering on April , , in partial fulfillment of the requirements for the degree of Doctor of Philosophy Abstract In this thesis, I discuss the application and development of methods for the automated discovery of motifs in sequential data. ese data include DNA sequences, protein sequences, and real– valued sequential data such as protein structures and timeseries of arbitrary dimension. As more genomes are sequenced and annotated, the need for automated, computational methods for analyzing biological data is increasing rapidly. In broad terms, the goal of this thesis is to treat sequential data sets as unknown languages and to develop tools for interpreting an understanding these languages. e first chapter of this thesis is an introduction to the fundamentals of motif discovery, which establishes a common mode of thought and vocabulary for the subsequent chapters. One of the central themes of this work is the use of grammatical models, which are more commonly associated with the field of computational linguistics. In the second chapter, I use grammatical models to design novel antimicrobial peptides (AmPs). AmPs are small proteins used by the innate immune system to combat bacterial infection in multicellular eukaryotes. -
A General Pairwise Interaction Model Provides an Accurate Description of in Vivo Transcription Factor Binding Sites
A General Pairwise Interaction Model Provides an Accurate Description of In Vivo Transcription Factor Binding Sites Marc Santolini, Thierry Mora, Vincent Hakim* Laboratoire de Physique Statistique, CNRS, Universite´ P. et M. Curie, Universite´ D. Diderot, E´cole Normale Supe´rieure, Paris, France Abstract The identification of transcription factor binding sites (TFBSs) on genomic DNA is of crucial importance for understanding and predicting regulatory elements in gene networks. TFBS motifs are commonly described by Position Weight Matrices (PWMs), in which each DNA base pair contributes independently to the transcription factor (TF) binding. However, this description ignores correlations between nucleotides at different positions, and is generally inaccurate: analysing fly and mouse in vivo ChIPseq data, we show that in most cases the PWM model fails to reproduce the observed statistics of TFBSs. To overcome this issue, we introduce the pairwise interaction model (PIM), a generalization of the PWM model. The model is based on the principle of maximum entropy and explicitly describes pairwise correlations between nucleotides at different positions, while being otherwise as unconstrained as possible. It is mathematically equivalent to considering a TF-DNA binding energy that depends additively on each nucleotide identity at all positions in the TFBS, like the PWM model, but also additively on pairs of nucleotides. We find that the PIM significantly improves over the PWM model, and even provides an optimal description of TFBS statistics within statistical noise. The PIM generalizes previous approaches to interdependent positions: it accounts for co-variation of two or more base pairs, and predicts secondary motifs, while outperforming multiple-motif models consisting of mixtures of PWMs. -
A New Sequence Logo Plot to Highlight Enrichment and Depletion
bioRxiv preprint doi: https://doi.org/10.1101/226597; this version posted November 29, 2017. 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. A new sequence logo plot to highlight enrichment and depletion. Kushal K. Dey 1, Dongyue Xie 1, Matthew Stephens 1, 2 1 Department of Statistics, University of Chicago 2 Department of Human Genetics, University of Chicago * Corresponding Email : [email protected] Abstract Background : Sequence logo plots have become a standard graphical tool for visualizing sequence motifs in DNA, RNA or protein sequences. However standard logo plots primarily highlight enrichment of symbols, and may fail to highlight interesting depletions. Current alternatives that try to highlight depletion often produce visually cluttered logos. Results : We introduce a new sequence logo plot, the EDLogo plot, that highlights both enrichment and depletion, while minimizing visual clutter. We provide an easy-to-use and highly customizable R package Logolas to produce a range of logo plots, including EDLogo plots. This software also allows elements in the logo plot to be strings of characters, rather than a single character, extending the range of applications beyond the usual DNA, RNA or protein sequences. We illustrate our methods and software on applications to transcription factor binding site motifs, protein sequence alignments and cancer mutation signature profiles. Conclusion : Our new EDLogo plots, and flexible software implementation, can help data analysts visualize both enrichment and depletion of characters (DNA sequence bases, amino acids, etc) across a wide range of applications. -
Predicting Expression Levels of De NovoProtein Designs in Yeast
Predicting expression levels of de novo protein designs in yeast through machine learning. Patrick Slogic A thesis submitted in partial fulfilment of the requirements for the degree of: Master of Science in Bioengineering University of Washington 2020 Committee: Eric Klavins Azadeh Yazdan-Shahmorad Program Authorized to Offer Degree: Bioengineering ©Copyright 2020 Patrick Slogic University of Washington Abstract Predicting expression levels of de novo protein designs in yeast through machine learning. Patrick Slogic Chair of the Supervisory Committee: Eric Klavins Department of Electrical and Computer Engineering Protein engineering has unlocked potential for the biomolecular synthesis of amino acid sequences with specified functions. With the many implications in enhancing therapy development, developing accurate functional models of recombinant genetic outcomes has shown great promise in unlocking the potential of novel protein structures. However, the complicated nature of structural determination requires an iterative process of design and testing among an enormous search space for potential designs. Expressed protein sequences through biological platforms are necessary to produce and analyze the functional efficacy of novel designs. In this study, machine learning principles are applied to a yeast surface display protocol with the goal of optimizing the search space of amino acid sequences that will express in yeast transformations. Machine learning networks are compared in predicting expression levels and generating similar sequences to find those likely to be successfully expressed. ACKNOWLEDGEMENTS I would like to thank Dr. Eric Klavins for accepting me as a master’s student in his laboratory and for providing direction and guidance in exploring the topics of machine learning and recombinant genetics throughout my graduate program in bioengineering. -
A Tool for Detecting Base Mis-Calls in Multiple Sequence Alignments by Semi-Automatic Chromatogram Inspection
ChromatoGate: A Tool for Detecting Base Mis-Calls in Multiple Sequence Alignments by Semi-Automatic Chromatogram Inspection Nikolaos Alachiotis Emmanouella Vogiatzi∗ Scientific Computing Group Institute of Marine Biology and Genetics HITS gGmbH HCMR Heidelberg, Germany Heraklion Crete, Greece [email protected] [email protected] Pavlos Pavlidis Alexandros Stamatakis Scientific Computing Group Scientific Computing Group HITS gGmbH HITS gGmbH Heidelberg, Germany Heidelberg, Germany [email protected] [email protected] ∗ Affiliated also with the Department of Genetics and Molecular Biology of the Democritian University of Thrace at Alexandroupolis, Greece. Corresponding author: Nikolaos Alachiotis Keywords: chromatograms, software, mis-calls Abstract Automated DNA sequencers generate chromatograms that contain raw sequencing data. They also generate data that translates the chromatograms into molecular sequences of A, C, G, T, or N (undetermined) characters. Since chromatogram translation programs frequently introduce errors, a manual inspection of the generated sequence data is required. As sequence numbers and lengths increase, visual inspection and manual correction of chromatograms and corresponding sequences on a per-peak and per-nucleotide basis becomes an error-prone, time-consuming, and tedious process. Here, we introduce ChromatoGate (CG), an open-source software that accelerates and partially automates the inspection of chromatograms and the detection of sequencing errors for bidirectional sequencing runs. To provide users full control over the error correction process, a fully automated error correction algorithm has not been implemented. Initially, the program scans a given multiple sequence alignment (MSA) for potential sequencing errors, assuming that each polymorphic site in the alignment may be attributed to a sequencing error with a certain probability. -
A Brief History of Sequence Logos
Biostatistics and Biometrics Open Access Journal ISSN: 2573-2633 Mini-Review Biostat Biometrics Open Acc J Volume 6 Issue 3 - April 2018 Copyright © All rights are reserved by Kushal K Dey DOI: 10.19080/BBOAJ.2018.06.555690 A Brief History of Sequence Logos Kushal K Dey* Department of Statistics, University of Chicago, USA Submission: February 12, 2018; Published: April 25, 2018 *Corresponding author: Kushal K Dey, Department of Statistics, University of Chicago, 5747 S Ellis Ave, Chicago, IL 60637, USA. Tel: 312-709- 0680; Email: Abstract For nearly three decades, sequence logo plots have served as the standard tool for graphical representation of aligned DNA, RNA and protein sequences. Over the years, a large number of packages and web applications have been developed for generating these logo plots and using them handling and the overall scope of these plots in biological applications and beyond. Here I attempt to review some popular tools for generating sequenceto identify logos, conserved with a patterns focus on in how sequences these plots called have motifs. evolved Also, over over time time, since we their have origin seen anda considerable how I view theupgrade future in for the these look, plots. flexibility of data Keywords : Graphical representation; Sequence logo plots; Standard tool; Motifs; Biological applications; Flexibility of data; DNA sequence data; Python library; Interdependencies; PLogo; Depletion of symbols; Alphanumeric strings; Visualizes pairwise; Oligonucleotide RNA sequence data; Visualize succinctly; Predictive power; Initial attempts; Widespread; Stylistic configurations; Multiple sequence alignment; Introduction based comparisons and predictions. In the next section, we The seeds of the origin of sequence logos were planted in review the modeling frameworks and functionalities of some of early 1980s when researchers, equipped with large amounts of these tools [5]. -
Bioinformatics Manual Sequence Data Analysis with CLC Main Workbench
Introduction to Molecular Biology and Bioinformatics Workshop Biosciences eastern and central Africa - International Livestock Research Institute Hub (BecA-ILRI Hub), Nairobi, Kenya May 5-16, 2014 Bioinformatics Manual Sequence data analysis with CLC Main Workbench Written and compiled by Joyce Njuguna, Mark Wamalwa, Rob Skilton 1 Getting started with CLC Main Workbench A. Quality control of sequenced data B. Assembling sequences C. Nucleotide and protein sequence manipulation D. BLAST sequence search E. Aligning sequences F. Building phylogenetic trees Welcome to CLC Main Workbench -- a user-friendly sequence analysis software package for analysing Sanger sequencing data and for supporting your daily bioinformatics work. Definition Sequence: the order of nucleotide bases [or amino acids] in a DNA [or protein] molecule DNA Sequencing: Biochemical methods used to determine the order of nucleotide bases, adenine(A), guanine(G),cytosine(C)and thymine(T) in a DNA strand TIP CLC Main Workbench includes an extensive Help function, which can be found in the Help menu of the program’s Menu bar. The Help can also be shown by pressing F1. The help topics are sorted in a table of contents and the topics can be searched. Also, it is recommended that you view the Online presentations where a product specialist from CLC bio demonstrates the software. This is a very easy way to get started using the program. Read more about online presentations here: http://clcbio.com/presentation. A. Getting Started with CLC Main Workbench 1. Download the trial version of CLC Main Workbench 6.8.1 from the following URL: http://www.clcbio.com/products/clc-main-workbench-direct-download/ 2. -
A STAT Protein Domain That Determines DNA Sequence Recognition Suggests a Novel DNA-Binding Domain
Downloaded from genesdev.cshlp.org on September 25, 2021 - Published by Cold Spring Harbor Laboratory Press A STAT protein domain that determines DNA sequence recognition suggests a novel DNA-binding domain Curt M. Horvath, Zilong Wen, and James E. Darnell Jr. Laboratory of Molecular Cell Biology, The Rockefeller University, New York, New York 10021 Statl and Stat3 are two members of the ligand-activated transcription factor family that serve the dual functions of signal transducers and activators of transcription. Whereas the two proteins select very similar (not identical) optimum binding sites from random oligonucleotides, differences in their binding affinity were readily apparent with natural STAT-binding sites. To take advantage of these different affinities, chimeric Statl:Stat3 molecules were used to locate the amino acids that could discriminate a general binding site from a specific binding site. The amino acids between residues -400 and -500 of these -750-amino-acid-long proteins determine the DNA-binding site specificity. Mutations within this region result in Stat proteins that are activated normally by tyrosine phosphorylation and that dimerize but have greatly reduced DNA-binding affinities. [Key Words: STAT proteins; DNA binding; site selection] Received January 6, 1995; revised version accepted March 2, 1995. The STAT (signal transducers and activators if transcrip- Whereas oligonucleotides representing these selected se- tion) proteins have the dual purpose of, first, signal trans- quences exhibited slight binding preferences, the con- duction from ligand-activated receptor kinase com- sensus sites overlapped sufficiently to be recognized by plexes, followed by nuclear translocation and DNA bind- both factors. However, by screening different natural ing to activate transcription (Darnell et al. -
Bioinformatics I Sanger Sequence Analysis
Updated: October 2020 Lab 5: Bioinformatics I Sanger Sequence Analysis Project Guide The Wolbachia Project Page Contents 3 Activity at a Glance 4 Technical Overview 5-7 Activity: How to Analyze Sanger Sequences 8 DataBase Entry 9 Appendix I: Illustrated BLAST Alignment 10 Appendix II: Sanger Sequencing Quick Reference Content is made available under the Creative Commons Attribution-NonCommercial-No Derivatives International License. Contact ([email protected]) if you would like to make adaptations for distribution beyond the classroom. The Wolbachia Project: Discover the Microbes Within! was developed by a collaboration of scientists, educators, and outreach specialists. It is directed by the Bordenstein Lab at Vanderbilt University. https://www.vanderbilt.edu/wolbachiaproject 2 Activity at a Glance Goals To analyze and interpret the quality of Sanger sequences To generate a consensus DNA sequence for bioinformatics analyses Learning Objectives Upon completion of this activity, students will (i) understand the Sanger method of sequencing, also known as the chain-termination method; (ii) be able to interpret chromatograms; (iii) evaluate sequencing Quality Scores; and (iv) generate a consensus DNA sequence based on forward and reverse Sanger reactions. Prerequisite Skills While no computer programming skills are necessary to complete this work, prior exposure to personal computers and the Internet is assumed. Teaching Time: One class period Recommended Background Tutorials • DNA Learning Center Animation: Sanger Method of -
Low-N Protein Engineering with Data-Efficient Deep Learning
bioRxiv preprint doi: https://doi.org/10.1101/2020.01.23.917682; this version posted January 24, 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. Low-N protein engineering with data-efficient deep learning 1† 3† 2† 2 1,4 Surojit Biswas , Grigory Khimulya , Ethan C. Alley , Kevin M. Esvelt , George M. Church 1 Wyss Institute for Biologically Inspired Engineering, Harvard University 2 MIT Media Lab, Massachusetts Institute of Technology 3 Somerville, MA 02143, USA 4 Department of Genetics, Harvard Medical School †These authors contributed equally to this work. *Correspondence to: George M. Church: gchurch{at}genetics.med.harvard.edu Abstract Protein engineering has enormous academic and industrial potential. However, it is limited by the lack of experimental assays that are consistent with the design goal and sufficiently high-throughput to find rare, enhanced variants. Here we introduce a machine learning-guided paradigm that can use as few as 24 functionally assayed mutant sequences to build an accurate virtual fitness landscape and screen ten million sequences via in silico directed evolution. As demonstrated in two highly dissimilar proteins, avGFP and TEM-1 β-lactamase, top candidates from a single round are diverse and as active as engineered mutants obtained from previous multi-year, high-throughput efforts. Because it distills information from both global and local sequence landscapes, our model approximates protein function even before receiving experimental data, and generalizes from only single mutations to propose high-functioning epistatically non-trivial designs.