A Revolution Toward Gene-Editing Technology and Its Application to Crop Improvement
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Expression of a Mouse Long Terminal Repeat Is Cell Cycle-Linked (Friend Cells/Gene Expression/Retroviruses/Transformation/Onc Genes) LEONARD H
Proc. Natl. Acad. Sci. USA Vol. 82, pp. 1946-1949, April 1985 Biochemistry Expression of a mouse long terminal repeat is cell cycle-linked (Friend cells/gene expression/retroviruses/transformation/onc genes) LEONARD H. AUGENLICHT AND HEIDI HALSEY Department of Oncology, Montefiore Medical Center, and Department of Medicine, Albert Einstein College of Medicine, 111 East 210th St., Bronx, NY 10467 Communicated by Harry Eagle, November 26, 1984 ABSTRACT The expression of the long terminal repeat have regions of homology with a Syrian hamster repetitive (LTR) of intracisternal A particle retroviral sequences which sequence whose expression is also linked to the G, phase of are endogenous to the mouse genome has been shown to be the cell cycle (28). linked to the early G6 phase of the cell cycle in Friend erythroleukemia cells synchronized by density arrest and also MATERIALS AND METHODS in logarithmically growing cells fractionated into cell-cycle Cells. Friend erythroleukemia cells, strain DS-19, were compartments by centrifugal elutriation. Regions of homology grown in minimal essential medium containing 10% fetal calf were found in comparing the LTR sequence to a repetitive serum (28). Cell number was determined by counting an Syrian hamster sequence specifically expressed in early G1 in aliquot in an automated particle counter (Coulter Electron- hamster cells. ics). The cells were fractionated into cell-cycle compart- ments by centrifugal elutriation with a Beckman elutriator The long terminal repeats (LTR) of retroviral genomes rotor as described (29). For analysis of DNA content per contain sequence elements that regulate the transcription of cell, the cells were stained with either 4',6-diamidino-2- the viral genes (1). -
RESEARCH ARTICLES Gene Cluster Statistics with Gene Families
RESEARCH ARTICLES Gene Cluster Statistics with Gene Families Narayanan Raghupathy*1 and Dannie Durand* *Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA; and Department of Computer Science, Carnegie Mellon University, Pittsburgh, PA Identifying genomic regions that descended from a common ancestor is important for understanding the function and evolution of genomes. In distantly related genomes, clusters of homologous gene pairs are evidence of candidate homologous regions. Demonstrating the statistical significance of such ‘‘gene clusters’’ is an essential component of comparative genomic analyses. However, currently there are no practical statistical tests for gene clusters that model the influence of the number of homologs in each gene family on cluster significance. In this work, we demonstrate empirically that failure to incorporate gene family size in gene cluster statistics results in overestimation of significance, leading to incorrect conclusions. We further present novel analytical methods for estimating gene cluster significance that take gene family size into account. Our methods do not require complete genome data and are suitable for testing individual clusters found in local regions, such as contigs in an unfinished assembly. We consider pairs of regions drawn from the same genome (paralogous clusters), as well as regions drawn from two different genomes (orthologous clusters). Determining cluster significance under general models of gene family size is computationally intractable. By assuming that all gene families are of equal size, we obtain analytical expressions that allow fast approximation of cluster probabilities. We evaluate the accuracy of this approximation by comparing the resulting gene cluster probabilities with cluster probabilities obtained by simulating a realistic, power-law distributed model of gene family size, with parameters inferred from genomic data. -
Gene-Pseudogene Evolution
Mahmudi et al. BMC Genomics 2015, 16(Suppl 10):S12 http://www.biomedcentral.com/1471-2164/16/S10/S12 RESEARCH Open Access Gene-pseudogene evolution: a probabilistic approach Owais Mahmudi1*, Bengt Sennblad2, Lars Arvestad3, Katja Nowick4, Jens Lagergren1* From 13th Annual Research in Computational Molecular Biology (RECOMB) Satellite Workshop on Comparative Genomics Frankfurt, Germany. 4-7 October 2015 Abstract Over the last decade, methods have been developed for the reconstruction of gene trees that take into account the species tree. Many of these methods have been based on the probabilistic duplication-loss model, which describes how a gene-tree evolves over a species-tree with respect to duplication and losses, as well as extension of this model, e.g., the DLRS (Duplication, Loss, Rate and Sequence evolution) model that also includes sequence evolution under relaxed molecular clock. A disjoint, almost as recent, and very important line of research has been focused on non protein-coding, but yet, functional DNA. For instance, DNA sequences being pseudogenes in the sense that they are not translated, may still be transcribed and the thereby produced RNA may be functional. We extend the DLRS model by including pseudogenization events and devise an MCMC framework for analyzing extended gene families consisting of genes and pseudogenes with respect to this model, i.e., reconstructing gene- trees and identifying pseudogenization events in the reconstructed gene-trees. By applying the MCMC framework to biologically realistic synthetic data, we show that gene-trees as well as pseudogenization points can be inferred well. We also apply our MCMC framework to extended gene families belonging to the Olfactory Receptor and Zinc Finger superfamilies. -
Gene Family Amplification Facilitates Adaptation in Freshwater Unionid
Gene family amplification facilitates adaptation in freshwater unionid bivalve Megalonaias nervosa Rebekah L. Rogers1∗, Stephanie L. Grizzard1;2, James E. Titus-McQuillan1, Katherine Bockrath3;4 Sagar Patel1;5;6, John P. Wares3;7, Jeffrey T Garner8, Cathy C. Moore1 Author Affiliations: 1. Department of Bioinformatics and Genomics, University of North Carolina, Charlotte, NC 2. Department of Biological Sciences, Old Dominion University, Norfolk, VA 3. Department of Genetics, University of Georgia, Athens, GA 4. U.S. Fish and Wildlife Service, Midwest Fisheries Center Whitney Genetics Lab, Onalaska, WI 5. Department of Biology, Saint Louis University, St. Louis, MO 6. Donald Danforth Plant Science Center, St. Louis, MO 7. Odum School of Ecology, University of Georgia, Athens, GA 8. Division of Wildlife and Freshwater Fisheries, Alabama Department of Conservation and Natural Resources, Florence, AL *Corresponding author: Department of Bioinformatics and Genomics, University of North Carolina, Charlotte, NC. [email protected] Keywords: Unionidae, M. nervosa, Evolutionary genomics, gene family expansion, arXiv:2008.00131v2 [q-bio.GN] 16 Nov 2020 transposable element evolution, Cytochrome P450, Population genomics, reverse ecological genetics Short Title: Gene family expansion in Megalonaias nervosa 1 Abstract Freshwater unionid bivalves currently face severe anthropogenic challenges. Over 70% of species in the United States are threatened, endangered or extinct due to pollution, damming of waterways, and overfishing. These species are notable for their unusual life history strategy, parasite-host coevolution, and biparental mitochondria inheritance. Among this clade, the washboard mussel Megalonaias nervosa is one species that remains prevalent across the Southeastern United States, with robust population sizes. We have created a reference genome for M. -
CRISPR/Cas9-Mediated Genome Editing Efficiently Creates Specific
www.nature.com/scientificreports Correction: Author Correction OPEN CRISPR/Cas9-mediated genome editing efciently creates specifc mutations at multiple loci using one Received: 18 April 2017 Accepted: 3 July 2017 sgRNA in Brassica napus Published: xx xx xxxx Hong Yang1, Jia-Jing Wu1, Ting Tang1, Ke-De Liu 2 & Cheng Dai1 CRISPR/Cas9 is a valuable tool for both basic and applied research that has been widely applied to diferent plant species. Nonetheless, a systematical assessment of the efciency of this method is not available for the allotetraploid Brassica napus—an important oilseed crop. In this study, we examined the mutation efciency of the CRISPR/Cas9 method for 12 genes and also determined the pattern, specifcity and heritability of these gene modifcations in B. napus. The average mutation frequency for a single-gene targeted sgRNA in the T0 generation is 65.3%. For paralogous genes located in conserved regions that were targeted by sgRNAs, we observed mutation frequencies that ranged from 27.6% to 96.6%. Homozygotes were readily found in T0 plants. A total of 48.2% of the gene mutations, including homozygotes, bi-alleles, and heterozygotes were stably inherited as classic Mendelian alleles in the next generation (T1) without any new mutations or reversions. Moreover, no mutation was found in the putative of-target sites among the examined T0 plants. Collectively, our results demonstrate that CRISPR/Cas9 is an efcient tool for creating targeted genome modifcations at multiple loci that are stable and inheritable in B. napus. These fndings open many doors for biotechnological applications in oilseed crops. -
Improving Treatment of Genetic Diseases with Crispr-Cas9 Rna-Guided Genome Editing
Sanchez 3:00 Team R06 Disclaimer: This paper partially fulfills a writing requirement for first-year (freshmen) engineering students at the University of Pittsburgh Swanson School of Engineering. This paper is a student paper, not a professional paper. This paper is not intended for publication or public circulation. This paper is based on publicly available information, and while this paper might contain the names of actual companies, products, and people, it cannot and does not contain all relevant information/data or analyses related to companies, products, and people named. All conclusions drawn by the authors are the opinions of the authors, first- year (freshmen) students completing this paper to fulfill a university writing requirement. If this paper or the information therein is used for any purpose other than the authors' partial fulfillment of a writing requirement for first-year (freshmen) engineering students at the University of Pittsburgh Swanson School of Engineering, the users are doing so at their own--not at the students', at the Swanson School's, or at the University of Pittsburgh's--risk. IMPROVING TREATMENT OF GENETIC DISEASES WITH CRISPR-CAS9 RNA-GUIDED GENOME EDITING Arijit Dutta [email protected] , Benjamin Ahlmark [email protected], Nate Majer [email protected] Abstract—Genetic illnesses are among the most difficult to treat as it is challenging to safely and effectively alter DNA. INTRODUCTION: THE WHAT, WHY, AND DNA is the basic code for all hereditary traits, so any HOW OF CRISPR-CAS9 alteration to DNA risks fundamentally altering the way someone’s genes are expressed. This change could lead to What Is CRISPR-Cas9? unintended consequences for both the individual whose DNA was altered and any offspring they may have in the future, CRISPR-Cas9 is an acronym that stands for “Clustered compounding the risk. -
Strategies for Precision Modulation of Gene Expression by Epigenome Editing: an Overview Benjamin I
Laufer and Singh Epigenetics & Chromatin (2015) 8:34 DOI 10.1186/s13072-015-0023-7 REVIEW Open Access Strategies for precision modulation of gene expression by epigenome editing: an overview Benjamin I. Laufer* and Shiva M. Singh Abstract Genome editing technology has evolved rather quickly and become accessible to most researchers. It has resulted in far reaching implications and a number of novel designer systems including epigenome editing. Epigenome editing utilizes a combination of nuclease-null genome editing systems and effector domains to modulate gene expression. In particular, Zinc Finger, Transcription-Activator-Like Effector, and CRISPR/Cas9 have emerged as modular systems that can be modified to allow for precision manipulation of epigenetic marks without altering underlying DNA sequence. This review contains a comprehensive catalog of effector domains that can be used with components of genome editing systems to achieve epigenome editing. Ultimately, the evidence-based design of epigenome editing offers a novel improvement to the limited attenuation strategies. There is much potential for editing and/or correcting gene expression in somatic cells toward a new era of functional genomics and personalized medicine. Keywords: Regulation of gene expression, Functional genomics, Stem cells, dCas9, CRISPR/Cas9, Zinc Finger, Transcription-Activator-Like Effector (TALE), Synthetic biology Background editing systems rely on two components, a DNA-bind- The modulation of gene expression can be achieved by ing element, and nuclease, to modify the targeted DNA a variety of biotechnologies such as RNA interference, sequence. Genome editing can be used to study protein non-precision drugs, and artificial transcription factors function by altering coding sequence or achieve tran- (ATFs). -
CRISPR Foki Dead Cas9 System: Principles and Applications in Genome Engineering
cells Review CRISPR FokI Dead Cas9 System: Principles and Applications in Genome Engineering Maryam Saifaldeen y, Dana E. Al-Ansari y , Dindial Ramotar * and Mustapha Aouida * College of Health and Life Sciences, Division of Biological and Biomedical Sciences, Hamad Bin Khalifa University, Education City, Qatar Foundation, Doha P.O.Box 34110, Qatar; [email protected] (M.S.); [email protected] (D.E.A.-A.) * Correspondence: [email protected] (D.R.); [email protected] (M.A.) These authors contributed equally to this work. y Received: 27 September 2020; Accepted: 19 November 2020; Published: 21 November 2020 Abstract: The identification of the robust clustered regularly interspersed short palindromic repeats (CRISPR) associated endonuclease (Cas9) system gene-editing tool has opened up a wide range of potential therapeutic applications that were restricted by more complex tools, including zinc finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs). Nevertheless, the high frequency of CRISPR system off-target activity still limits its applications, and, thus, advanced strategies for highly specific CRISPR/Cas9-mediated genome editing are continuously under development including CRISPR–FokI dead Cas9 (fdCas9). fdCas9 system is derived from linking a FokI endonuclease catalytic domain to an inactive Cas9 protein and requires a pair of guide sgRNAs that bind to the sense and antisense strands of the DNA in a protospacer adjacent motif (PAM)-out orientation, with a defined spacer sequence range around the target site. The dimerization of FokI domains generates DNA double-strand breaks, which activates the DNA repair machinery and results in genomic edit. So far, all the engineered fdCas9 variants have shown promising gene-editing activities in human cells when compared to other platforms. -
Genome Organization/ Human
Genome Organization/ Secondary article Human Article Contents . Introduction David H Kass, Eastern Michigan University, Ypsilanti, Michigan, USA . Sequence Complexity Mark A Batzer, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA . Single-copy Sequences . Repetitive Sequences . The human nuclear genome is a highly complex arrangement of two sets of 23 Macrosatellites, Minisatellites and Microsatellites . chromosomes, or DNA molecules. There are various types of DNA sequences and Gene Families . chromosomal arrangements, including single-copy protein-encoding genes, repetitive Gene Superfamilies . sequences and spacer DNA. Transposable Elements . Pseudogenes . Mitochondrial Genome Introduction . Genome Evolution . Acknowledgements The human nuclear genome contains 3000 million base pairs (bp) of DNA, of which only an estimated 3% possess protein-encoding sequences. As shown in Figure 1, the DNA sequences of the eukaryotic genome can be classified sequences such as the ribosomal RNA genes. Repetitive into several types, including single-copy protein-encoding sequences with no known function include the various genes, DNA that is present in more than one copy highly repeated satellite families, and the dispersed, (repetitive sequences) and intergenic (spacer) DNA. The moderately repeated transposable element families. The most complex of these are the repetitive sequences, some of remainder of the genome consists of spacer DNA, which is which are functional and some of which are without simply a broad category of undefined DNA sequences. function. Functional repetitive sequences are classified into The human nuclear genome consists of 23 pairs of dispersed and/or tandemly repeated gene families that chromosomes, or 46 DNA molecules, of differing sizes either encode proteins (and may include noncoding (Table 1). -
Role of Human Endogenous Retroviral Long Terminal Repeats (Ltrs) in Maintaining the Integrity of the Human Germ Line
Viruses 2011, 3, 901-905; doi:10.3390/v3060901 OPEN ACCESS viruses ISSN 1999-4915 www.mdpi.com/journal/viruses Commentary Role of Human Endogenous Retroviral Long Terminal Repeats (LTRs) in Maintaining the Integrity of the Human Germ Line Meihong Liu and Maribeth V. Eiden * Laboratory of Cellular and Molecular Regulation, National Institute of Mental Health, 49 Convent Drive MSC 4483, Bethesda, MD 20892, USA; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.:+1-301-402-1641 Fax: +1-301-402-1748. Received: 27 April 2011; in revised form: 10 June 2011 / Accepted: 15 June 2011 / Published: 21 June 2011 Abstract: Retroviruses integrate a reverse transcribed double stranded DNA copy of their viral genome into the chromosomal DNA of cells they infect. Occasionally, exogenous retroviruses infect germ cells and when this happens a profound shift in the virus host dynamic occurs. Retroviruses maintained as hereditable viral genetic material are referred to as endogenous retroviruses (ERVs). After millions of years of co-evolution with their hosts many human ERVs retain some degree of function and a few have even become symbionts. Thousands of copies of endogenous retrovirus long terminal repeats (LTRs) exist in the human genome. There are approximately 3000 to 4000 copies of the ERV-9 LTRs in the human genome and like other solo LTRs, ERV-9 LTRs can exhibit distinct promoter/enhancer activity in different cell lineages. It has been recently reported that a novel transcript of p63, a primordial member of the p53 family, is under the transcriptional control of an ERV-9 LTR [1]. -
A Member of a New Family of Telomeric Repeated Genesin Yeast
Copyright 0 1995 by the Genetics Society of America RTMl: A Member of a New Family of Telomeric Repeated Genesin Yeast Frederique Ness' and Michel Aigle Laboratoire de Ge'nitique, UPR CNRS 9026, Avenue des Facultis, F-33405 Talence Cedex, France Manuscript received November 7, 1994 Accepted for publication April 12, 1995 ABSTRACT Wehave isolateda newyeast gene called RTMl whoseoverexpression confers resistance to the toxicity of molasses. TheRTMl gene encodes a hydrophobic 34kD protein that contains seven potential transmembranespanning segments.Analysis of a series of industrial strains shows that the sequence is present in multiple copies and in variable locations in the genome. RTM loci arealways physically associated with SUC telomeric loci. The SUGRTM sequences are located between X and Y' subtelomeric sequences at chromosome ends. Surprisingly RTM sequences are not detected in the laboratory strain X2180. The lack of this sequence is associated with the absence of any SUC telomeric gene previously described. This observation raises the question of the origin of this nonessential gene. The particular subtelomeric position might explain the SUC-RTM sequence amplification observed in the genome of yeasts used in industrial biomass or ethanol production with molasses as substrate. This SUGRTM se- quence dispersion seems to be a good example of genomic rearrangement playing a role in evolution and environmental adaptation in these industrial yeasts. ENE overexpression or increase in the copy num- in Saccharomyces cermisim. Three families of duplicated G ber of a gene is a common adaptative mechanism genes illustrate the genetic polymorphism of the yeast exploited by different organisms to increase their resis- Saccharomyces and underline another gene amplifica- tance to various toxicagents. -
Characterization of the Long Terminal Repeat of the Endogenous
www.nature.com/scientificreports OPEN Characterization of the Long Terminal Repeat of the Endogenous Retrovirus-derived microRNAs in Received: 31 May 2018 Accepted: 12 September 2019 the Olive Flounder Published: xx xx xxxx Hee-Eun Lee1,2, Ara Jo1,2, Jennifer Im1,2, Hee-Jae Cha 3, Woo-Jin Kim4, Hyun Hee Kim5,6, Dong-Soo Kim7, Won Kim8, Tae-Jin Yang 9 & Heui-Soo Kim2,10 Endogenous retroviruses (ERVs) have been identifed at diferent copy numbers in various organisms. The long terminal repeat (LTR) element of an ERV has the capacity to exert regulatory infuence as both a promoter and enhancer of cellular genes. Here, we describe olive founder (OF)-ERV9, derived from chromosome 9 of the olive founder. OF-ERV9-LTR provide binding sites for various transcription factors and showed enhancer activity. The OF-ERV9-LTR demonstrates high sequence similarity with the 3′ untranslated region (UTR) of various genes that also contain seed sequences (TGTTTTG) that bind the LTR-derived microRNA(miRNA), OF-miRNA-307. Additionally, OF-miRNA-307 collaborates with transcription factors located in OF-ERV9-LTR to regulate gene expression. Taken together, our data facilitates a greater understanding of the molecular function of OF-ERV families and suggests that OF- miRNA-307 may act as a super-enhancer miRNA regulating gene activity. Paralichthys olivaceus, known as olive founder (OF) is an economically important marine fatfsh which is exten- sively cultured in Korea, China and Japan. Due to their high economic value, there are several selective breed- ing programs in place, such as those involving sex manipulation, owing to diferences in growth speed and size between male and female olive founders1–3.