Genetics and Genomics Commons^™

Intsormil- Centa’S New Bmr Sorghum Varieties Create A Surge In Dairy Production, René Clará Valencia

INTSORMIL Scientific Publications

Scientists from the INTSORMIL-CENTA project based at the National Center for Agricultural Technology and Forestry (CENTA) of El Salvador have worked for five years to develop varieties of sorghum for grain and forage that are highly nutritious to cattle. Using the gene bmr-12, received from Dr. Gebisa Ejeta of Purdue University, they combined commercial varieties CENTA S-2, S-3 CENTA, CENTA RCV and VG 146 and were able to form new varieties containing this same gene. The first generation created 76 new varieties.

Is Belief Larger Than Fact: Expectations, Optimism And Reality For Translational Stem Cell Research, Tania M. Bubela, Matthew D. Li, Mohamed Hafez, Mark Bieber, Harold Atkins

Office of the Provost

Background: Stem cell (SC) therapies hold remarkable promise for many diseases, but there is a significant gulf between public expectations and the reality of progress toward clinical application. Public expectations are fueled by stakeholder arguments for research and public funding, coupled with intense media coverage in an ethically charged arena. We examine media representations in light of the expanding global landscape of SC clinical trials, asking what patients may realistically expect by way of timelines for the therapeutic and curative potential of regenerative medicine?
Methods: We built 2 international datasets: (1) 3,404 clinical trials (CT) containing 'stem cell*' from ClinicalTrials.gov …

Phylogeny And Evolutionary Patterns In The Dwarf Crayfish Subfamily (Decapoda: Cambarellinae), C. Pedraza-Lara, I. Doadrio, J. Breinholt, Keith A. Crandall

Computational Biology Institute

The Dwarf crayfish or Cambarellinae, is a morphologically singular subfamily of decapod crustaceans that contains only one genus, Cambarellus. Its intriguing distribution, along the river basins of the Gulf Coast of United States (Gulf Group) and into Central México (Mexican Group), has until now lacked of satisfactory explanation. This study provides a comprehensive sampling of most of the extant species of Cambarellus and sheds light on its evolutionary history, systematics and biogeography. We tested the impact of Gulf Group versus Mexican Group geography on rates of cladogenesis using a maximum likelihood framework, testing different models of birth/extinction of lineages. We …

Scribble Acts In The Drosophila Fat-Hippo Pathway To Regulate Warts Activity, Shilpi Verghese, Indrayani Waghmare, Hailey Kwon, Katelin Hanes, Madhuri Kango-Singh

Biology Faculty Publications

Epithelial cells are the major cell-type for all organs in multicellular organisms. In order to achieve correct organ size, epithelial tissues need mechanisms that limit their proliferation, and protect tissues from damage caused by defective epithelial cells. Recently, the Hippo signaling pathway has emerged as a major mechanism that orchestrates epithelial development. Hippo signaling is required for cells to stop proliferation as in the absence of Hippo signaling tissues continue to proliferate and produce overgrown organs or tumors. Studies in Drosophila have led the way in providing a framework for how Hippo alters the pattern of gene transcription in target …

Multifactorial Patterns Of Gene Expression In Colonic Epithelial Cells Predict Disease Phenotypes In Experimental Colitis, Aubrey Leigh Frantz, Maria E. C. Bruno, Eric William Rogier, Halide Tuna, Donald A. Cohen, Subbarao Bondada, Ralph Lakshman Chelvarajan, J. Anthony Brandon, C. Darrell Jennings, Charlotte S. Kaetzel

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Background— The pathogenesis of inflammatory bowel disease (IBD) is complex and the need to identify molecular biomarkers is critical. Epithelial cells play a central role in maintaining intestinal homeostasis. We previously identified five “signature” biomarkers in colonic epithelial cells (CEC) that are predictive of disease phenotype in Crohn's disease. Here we investigate the ability of CEC biomarkers to define the mechanism and severity of intestinal inflammation.

Methods— We analyzed the expression of RelA, A20, pIgR, tumor necrosis factor (TNF), and macrophage inflammatory protein (MIP)-2 in CEC of mice with dextran sodium sulfate (DSS) acute colitis or T-cell-mediated chronic colitis. …

Survey Of Endosymbionts In The Diaphorina Citri Metagenome And Assembly Of A Wolbachia Wdi Draft Genome, Surya Saha, Wayne B. Hunter, Justin Reese, J. Kent Morgan, Mizuri Marutani-Hert, Hong Huang, Magdalen Lindeberg

School of Information Faculty Publications

Diaphorina citri (Hemiptera: Psyllidae), the Asian citrus psyllid, is the insect vector of Ca. Liberibacter asiaticus, the causal agent of citrus greening disease. Sequencing of the D. citrimetagenome has been initiated to gain better understanding of the biology of this organism and the potential roles of its bacterial endosymbionts. To corroborate candidate endosymbionts previously identified by rDNA amplification, raw reads from the D. citri metagenome sequence were mapped to reference genome sequences. Results of the read mapping provided the most support for Wolbachia and an enteric bacterium most similar to Salmonella. Wolbachia-derived reads were extracted using …

Freq-Seq: A Rapid, Cost-Effective, Sequencing-Based Method To Determine Allele Frequencies Directly From Mixed Populations, Lon Chubiz, Ming-Chun Lee, Nigel Delaney, Christopher Marx

Biology Department Faculty Works

No abstract provided.

Escherichia Coli Recg Functionally Suppresses Human Bloom Syndrome Phenotypes, Michael W. Killen, Dawn M. Stults, William A. Wilson, Andrew J. Pierce

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Defects in the human BLM gene cause Bloom syndrome, notable for early development of tumors in a broad variety of tissues. On the basis of sequence similarity, BLM has been identified as one of the five human homologs of RecQ from Escherichia coli. Nevertheless, biochemical characterization of the BLM protein indicates far greater functional similarity to the E. coli RecG protein and there is no known RecG homolog in human cells. To explore the possibility that the shared biochemistries of BLM and RecG may represent an example of convergent evolution of cellular function where in humans BLM has evolved to …

Gene Expression Analysis Of A Murine Model With Pulmonary Vascular Remodeling Compared To End-Stage Ipah Lungs, Kayoko Shimodaira, Yoichiro Okubo, Eri Ochiai, Haruo Nakayama, Harutaka Katano, Megumi Wakayama, Minoru Shinozaki, Takao Ishiwatari, Daisuke Sasai, Naobumi Tochigi, Tetsuo Nemoto, Tsutomu Saji, Katsuhiko Kamei, Kazutoshi Shibuya

Microbiology, Immunology, and Molecular Genetics Faculty Publications

BACKGROUND: Idiopathic pulmonary arterial hypertension (IPAH) continues to be one of the most serious intractable diseases that might start with activation of several triggers representing the genetic susceptibility of a patient. To elucidate what essentially contributes to the onset and progression of IPAH, we investigated factors playing an important role in IPAH by searching discrepant or controversial expression patterns between our murine model and those previously published for human IPAH. We employed the mouse model, which induced muscularization of pulmonary artery leading to hypertension by repeated intratracheal injection of Stachybotrys chartarum, a member of nonpathogenic and ubiquitous fungus in our …

Cross-Ontology Multi-Level Association Rule Mining In The Gene Ontology., Prashanti Manda, Seval Ozkan, Hui Wang, Fiona M. Mccarthy, Susan M. Bridges

BCoE Publications

The Gene Ontology (GO) has become the internationally accepted standard for representing function, process, and location aspects of gene products. The wealth of GO annotation data provides a valuable source of implicit knowledge of relationships among these aspects. We describe a new method for association rule mining to discover implicit co-occurrence relationships across the GO sub-ontologies at multiple levels of abstraction. Prior work on association rule mining in the GO has concentrated on mining knowledge at a single level of abstraction and/or between terms from the same sub-ontology. We have developed a bottom-up generalization procedure called Cross-Ontology Data Mining-Level by …

Cephalopod Genomics: A Plan Of Strategies And Organization, Caroline B. Albertin, Laure Bonnaud, C. Titus Brown, Wendy J. Crookes-Goodson, Rute R. Da Fonseca, Carlo Di Cristo, Brian P. Dilkes, Eric Edsinger-Gonzales, Robert M. Freeman Jr., Roger T. Hanlon, Kristen M. Koenig, Annie R. Lindgren, Mark Q. Martindale, Patrick Minx, Leonid L. Moroz, Marie-Therese Nödl, Spencer V. Nyholm, Atsushi Ogura, Judit R. Pungor, Joshua J. C. Rosenthal, Erich M. Schwarz, Shuichi Shigeno, Jan M. Strugnell, Tim Wollesen, Guojie Zhang, Clifton W. Ragsdale

Biology Faculty Publications and Presentations

The Cephalopod Sequencing Consortium (CephSeq Consortium) was established at a NESCent Catalysis Group Meeting, “Paths to Cephalopod Genomics- Strategies, Choices, Organization,” held in Durham, North Carolina, USA on May 24-27, 2012. Twenty-eight participants representing nine countries (Austria, Australia, China, Denmark, France, Italy, Japan, Spain and the USA) met to address the pressing need for genome sequencing of cephalopod mollusks. This group, drawn from cephalopod biologists, neuroscientists, developmental and evolutionary biologists, materials scientists, bioinformaticians and researchers active in sequencing, assembling and annotating genomes, agreed on a set of cephalopod species of particular importance for initial sequencing and developed strategies and an …

Genetic Diversity Of Neotropical Myotis (Chiroptera: Vespertilionidae) With An Emphasis On South American Species, Roxanne J. Larsen, Michelle C. Knapp, Hugh H. Genoways, Faisal Ali Anwarali Khan, Peter A. Larsen, Don E. Wilson, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

Background: Cryptic morphological variation in the Chiropteran genus Myotis limits the understanding of species boundaries and species richness within the genus. Several authors have suggested that it is likely there are unrecognized species-level lineages of Myotis in the Neotropics. This study provides an assessment of the diversity in New World Myotis by analyzing cytochrome-b gene variation from an expansive sample ranging throughout North, Central, and South America. We provide baseline genetic data for researchers investigating phylogeographic and phylogenetic patterns of Myotis in these regions, with an emphasis on South America.

Methodology and Principal Findings: Cytochrome-b sequences were generated and …

The Consequences Of Denoising Marker-Based Metagenomic Data, John M. Gaspar, W. K. Thomas

Molecular, Cellular & Biomedical Sciences

No abstract provided.

Serotonin System Gene Polymorphisms Are Associated With Impulsivity In A Context Dependent Manner, Scott F. Stoltenberg, Christa C. Christ, Krista B. Highland

Department of Psychology: Faculty Publications

Impulsivity is a risk factor for adverse outcomes and characterizes several psychiatric disorders and risk for suicide. There is strong evidence that genetic variation influences individual differences in impulsivity, but the details are not yet understood. There is growing interest in better understanding the context dependency of genetic effects that is reflected in studies examining gender specificity, gene × environment interaction and epistasis (gene-gene interaction). In a cross-sectional study we examined whether polymorphisms in six serotonin system candidate genes and the experience of early life trauma (age 0–12) were associated with individual differences in impulsivity in a nonclinical sample of …

The Search, The Jackson Laboratory

Search Magazine

No abstract provided.

Phylogenetics Links Monster Larva To Deep-Sea Shrimp., Heather D Bracken-Grissom, Darryl L Felder, Nicole L Vollmer, Joel W Martin, Keith A Crandall

Computational Biology Institute

Mid-water plankton collections commonly include bizarre and mysterious developmental stages that differ conspicuously from their adult counterparts in morphology and habitat. Unaware of the existence of planktonic larval stages, early zoologists often misidentified these unique morphologies as independent adult lineages. Many such mistakes have since been corrected by collecting larvae, raising them in the lab, and identifying the adult forms. However, challenges arise when the larva is remarkably rare in nature and relatively inaccessible due to its changing habitats over the course of ontogeny. The mid-water marine species Cerataspis monstrosa (Gray 1828) is an armored crustacean larva whose adult identity …

Some Like It Hot, Some Like It Warm: Phenotyping To Explore Thermotolerance Diversity, C. H. Yeh, Nicholas J. Kaplinsky, C. Hu, Y. Y. Charng

Biology Faculty Works

Plants have evolved overlapping but distinct cellular responses to different aspects of high temperature stress. These responses include basal thermotolerance, short- and long-term acquired thermotolerance, and thermotolerance to moderately high temperatures. This ‘thermotolerance diversity’ means that multiple phenotypic assays are essential for fully describing the functions of genes involved in heat stress responses. A large number of genes with potential roles in heat stress responses have been identified using genetic screens and genome wide expression studies. We examine the range of phenotypic assays that have been used to characterize thermotolerance phenotypes in both Arabidopsis and crop plants. Three major variables …

Development And Characterization Of 11 Novel Microsatellite Loci For The Roundscale Spearfish Tetrapturus Georgii And Their Cross-Species Amplification Among Other Istiophorid Species, Andrea M. Bernard, Kevin A. Feldheim, Mahmood S. Shivji

Marine & Environmental Sciences Faculty Articles

Eleven novel polymorphic microsatellite loci were developed and characterized for the recently validated roundscale spearfish Tetrapturus georgii. Characterization of these markers, based on 35 roundscale spearfish from the western North Atlantic, revealed two to 21 alleles per locus with an average expected heterozygosity (HE) of 0·09–0·94, and all loci conformed to Hardy–Weinberg expectations. Cross-amplification of these 11 loci against all other eight known istiophorid species indicates promising prospects for the utility of these markers for istiophorids in general.

One Can’T Stand On Its Own: Are Non-Luminescence Traits Necessary For V. Fischeri Colonization Of E. Scolopes?, Feier Liu

Honors Theses and Capstones

Vibrio fischeri and Euprymna scolopes squid establish mutualistic symbiosis and select for each other in the natural environment. V. fischeri provides bioluminescent camouflage for E. scolopes while E. scolopes provides nutrients for V. fischeri. The most intriguing aspect of this relationship is that E. scolopes is highly selective and only allows sustained colonization by luminous, but not dark V. fischeri. Luminescence is the key symbiosis trait; however, other bacterial factors may also allow squid recognition. We hypothesized that there are luminescence linked traits that contribute to colonization. V. fischeri with luminescence variation was isolated and tested for oxidative resistance, …

Gametes: A Fast, Direct Algorithm For Generating Pure, Strict, Epistatic Models With Random Architectures, Ryan J. Urbanowicz, Jeff Kiralis, Nicholas A. Sinnott-Armstrong, Tamra Heberling, Jonathan M. Fisher, Jason H. Moore

Dartmouth Scholarship

Background: Geneticists who look beyond single locus disease associations require additional strategies for the detection of complex multi-locus effects. Epistasis, a multi-locus masking effect, presents a particular challenge, and has been the target of bioinformatic development. Thorough evaluation of new algorithms calls for simulation studies in which known disease models are sought. To date, the best methods for generating simulated multi-locus epistatic models rely on genetic algorithms. However, such methods are computationally expensive, difficult to adapt to multiple objectives, and unlikely to yield models with a precise form of epistasis which we refer to as pure and strict. Purely and …

Organellar Signaling Expands Plant Phenotypic Variation And Increases The Potential For Breeding The Epigenome, Roberto De La Rosa Santamaria

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

MUTS HOMOLOGUE 1 (MSH1) is a nuclear gene unique to plants that functions in mitochondria and plastids, where it confers genome stability. Phenotypic effects of MSH1 down- regulation were studied in sorghum inbreed line Tx430 and Arabidopsis ecotype Columbia-0, with the hypothesis that RNAi suppression of MSH1 triggers retrograde signaling from organelles to the nucleus, alters the epigenome, and derives heritable phenotypic variation suitable for artificial selection. An array of morphological traits and metabolic pathways was detected, including leaf variegation, male sterility and dwarfism, associated with altered gibberellic acid metabolism, higher levels of reactive oxygen species (ROS), and decreased synthesis …

Characterization Of Xylan Utilization And Discovery Of A New Endoxylanase In Thermoanaerobacterium Saccharolyticum Through Targeted Gene Deletions, Kara K. Podkaminer, Adam M. Guss, Heather L. Trajano, David A. Hogsett, Lee R. Lynd

Dartmouth Scholarship

The economical production of fuels and commodity chemicals from lignocellulose requires the utilization of both the cellulose and hemicellulose fractions. Xylanase enzymes allow greater utilization of hemicellulose while also increasing cellulose hydrolysis. Recent metabolic engineering efforts have resulted in a strain of Thermoanaerobacterium saccharolyticum that can convert C5 and C6 sugars, as well as insoluble xylan, into ethanol at high yield. To better understand the process of xylan solubilization in this organism, a series of targeted deletions were constructed in the homoethanologenic T. saccharolyticum strain M0355 to characterize xylan hydrolysis and xylose utilization in this organism. While the deletion of …

Transcriptional Cross Talk Within The Mar-Sox-Rob Regulon In Escherichia Coli Is Limited To The Rob And Marrab Operons, Lon Chubiz, George Glekas, Christopher Rao

Biology Department Faculty Works

Bacteria possess multiple mechanisms to survive exposure to various chemical stresses and antimicrobial compounds. In the enteric bacterium Escherichia coli, three homologous transcription factors—MarA, SoxS, and Rob—play a central role in coordinating this response. Three separate systems are known to regulate the expression and activities of MarA, SoxS, and Rob. However, a number of studies have shown that the three do not function in isolation but rather are coregulated through transcriptional cross talk. In this work, we systematically investigated the extent of transcriptional cross talk in the mar-sox-rob regulon. While the three transcription factors were found to have the potential …

Phylotranscriptomics To Bring The Understudied Into The Fold: Monophyletic Ostracoda, Fossil Placement, And Pancrustacean Phylogeny, Todd H. Oakley, Joanna M. Wolfe, Annie R. Lindgren, Alexander K. Zaharoff

Biology Faculty Publications and Presentations

An ambitious, yet fundamental goal for comparative biology is to understand the evolutionary relationships for all of life. However, many important taxonomic groups have remained recalcitrant to inclusion into broader scale studies. Here, we focus on collection of 9 new 454 transcriptome data sets from Ostracoda, an ancient and diverse group with a dense fossil record, which is often undersampled in broader studies. We combine the new transcriptomes with a new morphological matrix (including fossils) and existing expressed sequence tag, mitochondrial genome, nuclear genome, and ribosomal DNA data. Our analyses lead to new insights into ostracod and pancrustacean phylogeny. We …

Insights Into Mrnp Biogenesis Provided By New Genetic Interactions Among Export And Transcription Factors, Francisco Estruch, Christine Hodge, Natalia Gómez-Navarro, Lorena Peiró-Chova, Catherine V. Heath, Charles N. Cole

Dartmouth Scholarship

The various steps of mRNP biogenesis (transcription, processing and export) are interconnected. It has been shown that the transcription machinery plays a pivotal role in mRNP assembly, since several mRNA export factors are recruited during transcription and physically interact with components of the transcription machinery. Although the shuttling DEAD-box protein Dbp5p is concentrated on the cytoplasmic fibrils of the NPC, previous studies demonstrated that it interacts physically and genetically with factors involved in transcription initiation. We investigated the effect of mutations affecting various components of the transcription initiation apparatus on the phenotypes of mRNA export mutant strains. Our results show …

Role Of Histone Modifications In Meiosis, Mason Allen, Neeraj Joshi

Undergraduate Research Posters 2012

Meiosis I is characterized by events taking place between homologous chromosomes called crossing over in which double stand breaks (DSB) are formed and repaired using the homologous chromosome as a template. To see if Gene A shared the same role as Gene B, double mutants were created to test chromosome segregation and DSB repair as compared with Gene B deletions. The spore viability of double mutants and their potential implications will be discussed.

Structure-Function Of U11 Snrna In The Minor Splicing Pathway, Mark P. Biro, Jagjit Singh

Undergraduate Research Posters 2012

In human, the majority of protein coding genes are interrupted by dispensable intervening sequences (introns). These introns are removed by nuclear precursor (pre) mRNA splicing process to produce a mature mRNA needed for productive protein production in the cell. We are studying the splicing of minor class or U12-type introns which are spliced by U11, U12, U4atac, U5 and U6atac snRNAs. U11 snRNA binds to the 5’ end or splice site of the intron by RNA-RNA base-pairing to initiate the splicing process. Our results show the functionality of the genetic mutation suppressor assay in establishing the role of U11 snRNA …

Identification Of Novel Meiotic Genes Via A Genetic Screen, Steven David Zimmerman, Rima Sandhu

Undergraduate Research Posters 2012

Proper segregation of chromosomes in Meiosis I requires proper function of the Synaptonemal Complex (SC), a zipper-like protein structure that facilitates recombination events and segregation of homologous chromosomes. Candidates which suppress the phenotype show sporulation and fluorescence on media, and have higher spore viabilities compared to our Zip1C1 control.

Yeast 2-Hybrid Screen For T. Brucei Tin2- And Rap1- Intracting Proteins, Miao Wang, Fan Wu

Undergraduate Research Posters 2012

Telomeres are DNA-protein complexes located at the ends of linear chromosomes. Acting like a cap, they protect chromosome ends from degradation and rearrangement, maintaining genomic stability. Our lab has identified several T. brucei telomere proteins, including TRF (TTAGGG Repeat-binding Factor), TIN2 (TRF1-interacting Nulcear Protein 2) and RAP1 (Repressor Activator Protein 1) homologs. We are currently verifying the interactions between the new candidates and TbTIN2 or TbRAP1.

Sequencing And Analysis Of The Gastrula Transcriptome Of The Brittle Star Ophiocoma Wendtii, Roy Vaughn, Nancy Garnhart, James R. Garey, W. Kelley Thomas, Brian T. Livingston

Hubbard Center for Genome Studies (HCGS)

Background

The gastrula stage represents the point in development at which the three primary germ layers diverge. At this point the gene regulatory networks that specify the germ layers are established and the genes that define the differentiated states of the tissues have begun to be activated. These networks have been well-characterized in sea urchins, but not in other echinoderms. Embryos of the brittle star Ophiocoma wendtii share a number of developmental features with sea urchin embryos, including the ingression of mesenchyme cells that give rise to an embryonic skeleton. Notable differences are that no micromeres are formed during cleavage …