scholarly journals Conserved Vertebrate Chromosome Segments in the Large Salamander Genome

Genetics ◽  
2001 ◽  
Vol 158 (2) ◽  
pp. 735-746 ◽  
Author(s):  
S Randal Voss ◽  
Jeramiah J Smith ◽  
David M Gardiner ◽  
David M Parichy
Keyword(s):  
Small Sample ◽  
Ambystoma Mexicanum ◽  
Model Organisms ◽  
Genetic Linkage Analysis ◽  
Protein Coding ◽  
Mapping Panel ◽  
Organ Systems ◽  
Vertebrate Model ◽  
Ambystomatid Salamanders ◽  
Chromosome Segments

Abstract Urodele amphibians (salamanders) are important models for embryological, physiological, and natural history research and are also a biomedically important group because they are the only vertebrates capable of regenerating entire organ systems. To enhance the utility of salamanders for biomedical research and for understanding genome evolution, genetic linkage analysis was used to identify chromosome segments that are homologous between ambystomatid salamanders and distantly related vertebrate model organisms. A total of 347 loci (AFLPs, RAPDs, and protein-coding loci) were mapped using an interspecific meiotic mapping panel (Ambystoma mexicanum and A. tigrinum tigrinum; family Ambystomatidae). Genome size in Ambystoma was estimated to be 7291 cM, the largest linkage map estimate reported for any organism. However, the relatively large size of the salamander genome did not hinder efforts to map and identify conserved syntenies from a small sample of 24 protein-coding loci. Chromosomal segments that are conserved between fishes and mammals are also conserved in these salamanders. Thus, comparative gene mapping appears to be an efficient strategy for identifying orthologous loci between ambystomatid salamanders and genomically well-characterized vertebrate model organisms.

Analysis of Inter-Chromosomal Distribution of Disease-Related Genes in Human Genome

2020 ◽  
Vol 21 (11) ◽  
pp. 1068-1077
Author(s):  
Xiaochao Sun ◽  
Bin Yang ◽  
Qunye Zhang
Keyword(s):  
Spatial Distribution ◽  
Model Organisms ◽  
Nucleotide Polymorphisms ◽  
Chromosomal Distribution ◽  
Single Nucleotide ◽  
Protein Coding ◽  
Single Chromosome ◽  
Deletion Mutations ◽  
Protein Coding Genes ◽  
Disease Related Genes

: Many studies have shown that the spatial distribution of genes within a single chromosome exhibits distinct patterns. However, little is known about the characteristics of inter-chromosomal distribution of genes (including protein-coding genes, processed transcripts and pseudogenes) in different genomes. In this study, we explored these issues using the available genomic data of both human and model organisms. Moreover, we also analyzed the distribution pattern of protein-coding genes that have been associated with 14 common diseases and the insert/deletion mutations and single nucleotide polymorphisms detected by whole genome sequencing in an acute promyelocyte leukemia patient. We obtained the following novel findings. Firstly, inter-chromosomal distribution of genes displays a nonstochastic pattern and the gene densities in different chromosomes are heterogeneous. This kind of heterogeneity is observed in genomes of both lower and higher species. Secondly, protein-coding genes involved in certain biological processes tend to be enriched in one or a few chromosomes. Our findings have added new insights into our understanding of the spatial distribution of genome and disease- related genes across chromosomes. These results could be useful in improving the efficiency of disease-associated gene screening studies by targeting specific chromosomes.

scholarly journals Identification of high-efficiency 3′GG gRNA motifs in indexed FASTA files with ngg2

2015 ◽  
Vol 1 ◽  
pp. e33 ◽  
Author(s):  
Elisha D. Roberson
Keyword(s):  
High Efficiency ◽  
Homo Sapiens ◽  
Model Organisms ◽  
Proof Of Concept ◽  
Protein Coding ◽  
C Elegans ◽  
Protein Coding Genes ◽  
Starting Point ◽  
Command Line Tool ◽  
Reference Genomes

CRISPR/Cas9 is emerging as one of the most-used methods of genome modification in organisms ranging from bacteria to human cells. However, the efficiency of editing varies tremendously site-to-site. A recent report identified a novel motif, called the 3′GG motif, which substantially increases the efficiency of editing at all sites tested inC. elegans. Furthermore, they highlighted that previously published gRNAs with high editing efficiency also had this motif. I designed a Python command-line tool, ngg2, to identify 3′GG gRNA sites from indexed FASTA files. As a proof-of-concept, I screened for these motifs in six model genomes:Saccharomyces cerevisiae,Caenorhabditis elegans,Drosophila melanogaster,Danio rerio,Mus musculus, andHomo sapiens. I also scanned the genomes of pig (Sus scrofa) and African elephant (Loxodonta africana) to demonstrate the utility in non-model organisms. I identified more than 60 million single match 3′GG motifs in these genomes. Greater than 61% of all protein coding genes in the reference genomes had at least one unique 3′GG gRNA site overlapping an exon. In particular, more than 96% of mouse and 93% of human protein coding genes have at least one unique, overlapping 3′GG gRNA. These identified sites can be used as a starting point in gRNA selection, and the ngg2 tool provides an important ability to identify 3′GG editing sites in any species with an available genome sequence.

scholarly journals Genome sequence of the model rice variety KitaakeX

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Rashmi Jain ◽  
Jerry Jenkins ◽  
Shengqiang Shu ◽  
Mawsheng Chern ◽  
Joel A. Martin ◽  
...  
Keyword(s):  
Functional Genomics ◽  
De Novo ◽  
Rice Variety ◽  
Rice Genome ◽  
Life Cycles ◽  
Model Organisms ◽  
High Quality ◽  
Rice Varieties ◽  
Protein Coding ◽  
High Quality Genome

Abstract Background The availability of thousands of complete rice genome sequences from diverse varieties and accessions has laid the foundation for in-depth exploration of the rice genome. One drawback to these collections is that most of these rice varieties have long life cycles, and/or low transformation efficiencies, which limits their usefulness as model organisms for functional genomics studies. In contrast, the rice variety Kitaake has a rapid life cycle (9 weeks seed to seed) and is easy to transform and propagate. For these reasons, Kitaake has emerged as a model for studies of diverse monocotyledonous species. Results Here, we report the de novo genome sequencing and analysis of Oryza sativa ssp. japonica variety KitaakeX, a Kitaake plant carrying the rice XA21 immune receptor. Our KitaakeX sequence assembly contains 377.6 Mb, consisting of 33 scaffolds (476 contigs) with a contig N50 of 1.4 Mb. Complementing the assembly are detailed gene annotations of 35,594 protein coding genes. We identified 331,335 genomic variations between KitaakeX and Nipponbare (ssp. japonica), and 2,785,991 variations between KitaakeX and Zhenshan97 (ssp. indica). We also compared Kitaake resequencing reads to the KitaakeX assembly and identified 219 small variations. The high-quality genome of the model rice plant KitaakeX will accelerate rice functional genomics. Conclusions The high quality, de novo assembly of the KitaakeX genome will serve as a useful reference genome for rice and will accelerate functional genomics studies of rice and other species.

scholarly journals From raw materials to validated system: the construction of a genomic library and microarray to interpret systemic perturbations in Northern bobwhite

2010 ◽  
Vol 42 (2) ◽  
pp. 219-235 ◽  
Author(s):  
Arun Rawat ◽  
Kurt A. Gust ◽  
Youping Deng ◽  
Natàlia Garcia-Reyero ◽  
Michael J. Quinn ◽  
...  
Keyword(s):  
Genomic Library ◽  
Raw Materials ◽  
Research Effort ◽  
Northern Bobwhite ◽  
Protein Domain ◽  
Model Organisms ◽  
Protein Coding ◽  
Genomic Tools ◽  
Ppar Signaling ◽  
Genome Analyses

The limited availability of genomic tools and data for nonmodel species impedes computational and systems biology approaches in nonmodel organisms. Here we describe the development, functional annotation, and utilization of genomic tools for the avian wildlife species Northern bobwhite ( Colinus virginianus ) to determine the molecular impacts of exposure to 2,6-dinitrotoluene (2,6-DNT), a field contaminant of military concern. Massively parallel pyrosequencing of a normalized multitissue library of Northern bobwhite cDNAs yielded 71,384 unique transcripts that were annotated with gene ontology (GO), pathway information, and protein domain analysis. Comparative genome analyses with model organisms revealed functional homologies in 8,825 unique Northern bobwhite genes that are orthologous to 48% of Gallus gallus protein-coding genes. Pathway analysis and GO enrichment of genes differentially expressed in livers of birds exposed for 60 days (d) to 10 and 60 mg/kg/d 2,6-DNT revealed several impacts validated by RT-qPCR including: prostaglandin pathway-mediated inflammation, increased expression of a heme synthesis pathway in response to anemia, and a shift in energy metabolism toward protein catabolism via inhibition of control points for glucose and lipid metabolic pathways, PCK1 and PPARGC1, respectively. This research effort provides the first comprehensive annotated gene library for Northern bobwhite. Transcript expression analysis provided insights into the metabolic perturbations underlying several observed toxicological phenotypes in a 2,6-DNT exposure case study. Furthermore, the systemic impact of dinitrotoluenes on liver function appears conserved across species as PPAR signaling is similarly affected in fathead minnow liver tissue after exposure to 2,4-DNT.

scholarly journals Transcriptome-wide Cas13 guide RNA design for model organisms and viral RNA pathogens

2020 ◽  
Author(s):  
Xinyi Guo ◽  
Hans-Hermann Wessels ◽  
Alejandro Méndez-Mancilla ◽  
Daniel Haro ◽  
Neville E. Sanjana
Keyword(s):  
Rna Virus ◽  
H1n1 Influenza ◽  
Model Organisms ◽  
Messenger Rnas ◽  
Protein Coding ◽  
Guide Rna ◽  
Knock Down ◽  
Guide Rnas ◽  
Rna Targeting ◽  
Rna Design

AbstractCRISPR-Cas13 mediates robust transcript knockdown in human cells through direct RNA targeting. Compared to DNA-targeting CRISPR enzymes like Cas9, RNA targeting by Cas13 is transcript- and strand-specific: It can distinguish and specifically knock-down processed transcripts, alternatively spliced isoforms and overlapping genes, all of which frequently serve different functions. Previously, we identified optimal design rules for RfxCas13d guide RNAs (gRNAs), and developed a computational model to predict gRNA efficacy for all human protein-coding genes. However, there is a growing interest to target other types of transcripts, such as noncoding RNAs (ncRNAs) or viral RNAs, and to target transcripts in other commonly-used organisms. Here, we predicted relative Cas13-driven knock-down for gRNAs targeting messenger RNAs and ncRNAs in six model organisms (human, mouse, zebrafish, fly, nematode and flowering plants) and four abundant RNA virus families (SARS-CoV-2, HIV-1, H1N1 influenza and MERS). To allow for more flexible gRNA efficacy prediction, we also developed a web-based application to predict optimal gRNAs for any RNA target entered by the user. Given the lack of Cas13 guide design tools, we anticipate this resource will facilitate CRISPR-Cas13 RNA targeting in common model organisms, emerging viral threats to human health, and novel RNA targets.

scholarly journals TALPID3 controls centrosome and cell polarity and the human ortholog KIAA0586 is mutated in Joubert syndrome (JBTS23)

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Louise A Stephen ◽  
Hasan Tawamie ◽  
Gemma M Davis ◽  
Lars Tebbe ◽  
Peter Nürnberg ◽  
...  
Keyword(s):  
Cell Polarity ◽  
Protein Localization ◽  
Splice Site Mutation ◽  
Joubert Syndrome ◽  
Homozygosity Mapping ◽  
Model Organisms ◽  
Site Mutation ◽  
Whole Exome ◽  
Organ Systems ◽  
Human Ortholog

Joubert syndrome (JBTS) is a severe recessive neurodevelopmental ciliopathy which can affect several organ systems. Mutations in known JBTS genes account for approximately half of the cases. By homozygosity mapping and whole-exome sequencing, we identified a novel locus, JBTS23, with a homozygous splice site mutation in KIAA0586 (alias TALPID3), a known lethal ciliopathy locus in model organisms. Truncating KIAA0586 mutations were identified in two additional patients with JBTS. One mutation, c.428delG (p.Arg143Lysfs*4), is unexpectedly common in the general population and may be a major contributor to JBTS. We demonstrate KIAA0586 protein localization at the basal body in human and mouse photoreceptors, as is common for JBTS proteins, and also in pericentriolar locations. We show that loss of TALPID3 (KIAA0586) function in animal models causes abnormal tissue polarity, centrosome length and orientation, and centriolar satellites. We propose that JBTS and other ciliopathies may in part result from cell polarity defects.

scholarly journals Finding MEMO—Emerging Evidence for MEMO1′s Function in Development and Disease

Genes ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1316
Author(s):  
Michaela D. Schotanus ◽  
Eric Van Otterloo
Keyword(s):  
Cancer Metastasis ◽  
Cell Types ◽  
Receptor Activation ◽  
Breast Cancer Metastasis ◽  
Model Organisms ◽  
Pathological State ◽  
Proteomic Screen ◽  
Open Questions ◽  
Cytoskeletal Regulation ◽  
Organ Systems

Although conserved throughout animal kingdoms, the protein encoded by the gene Mediator of ERBB2 Driven Cell Motility 1 or MEMO1, has only recently come into focus. True to its namesake, MEMO1 first emerged from a proteomic screen of molecules bound to the ERBB2 receptor and was found to be necessary for efficient cell migration upon receptor activation. While initially placed within the context of breast cancer metastasis—a pathological state that has provided tremendous insight into MEMO1′s cellular roles—MEMO1′s function has since expanded to encompass additional cancer cell types, developmental processes during embryogenesis and homeostatic regulation of adult organ systems. Owing to MEMO1′s deep conservation, a variety of model organisms have been amenable to uncovering biological facets of this multipurpose protein; facets ranging from the cellular (e.g., receptor signaling, cytoskeletal regulation, redox flux) to the organismal (e.g., mineralization and mineral homeostasis, neuro/gliogenesis, vasculogenesis) level. Although these facets emerge at the intersection of numerous biological and human disease processes, how and if they are interconnected remains to be resolved. Here, we review our current understanding of this ‘enigmatic’ molecule, its role in development and disease and open questions emerging from these previous studies.

scholarly journals Reference Genome for the Highly Transformable Setaria viridis ME034V

2020 ◽  
Vol 10 (10) ◽  
pp. 3467-3478 ◽  
Author(s):  
Peter M. Thielen ◽  
Amanda L. Pendleton ◽  
Robert A. Player ◽  
Kenneth V. Bowden ◽  
Thomas J. Lawton ◽  
...  
Keyword(s):  
De Novo ◽  
Gene Families ◽  
Model Organisms ◽  
Phylogenomic Analysis ◽  
Setaria Viridis ◽  
Sequencing Technology ◽  
Protein Coding ◽  
Genotype Frequencies ◽  
Green Foxtail ◽  
Genome Assemblies

Setaria viridis (green foxtail) is an important model system for improving cereal crops due to its diploid genome, ease of cultivation, and use of C4 photosynthesis. The S. viridis accession ME034V is exceptionally transformable, but the lack of a sequenced genome for this accession has limited its utility. We present a 397 Mb highly contiguous de novo assembly of ME034V using ultra-long nanopore sequencing technology (read N50 = 41kb). We estimate that this genome is largely complete based on our updated k-mer based genome size estimate of 401 Mb for S. viridis. Genome annotation identified 37,908 protein-coding genes and >300k repetitive elements comprising 46% of the genome. We compared the ME034V assembly with two other previously sequenced Setaria genomes as well as to a diversity panel of 235 S. viridis accessions. We found the genome assemblies to be largely syntenic, but numerous unique polymorphic structural variants were discovered. Several ME034V deletions may be associated with recent retrotransposition of copia and gypsy LTR repeat families, as evidenced by their low genotype frequencies in the sampled population. Lastly, we performed a phylogenomic analysis to identify gene families that have expanded in Setaria, including those involved in specialized metabolism and plant defense response. The high continuity of the ME034V genome assembly validates the utility of ultra-long DNA sequencing to improve genetic resources for emerging model organisms. Structural variation present in Setaria illustrates the importance of obtaining the proper genome reference for genetic experiments. Thus, we anticipate that the ME034V genome will be of significant utility for the Setaria research community.

Mutant Generation in Vertebrate Model Organisms by TILLING

2011 ◽  
pp. 475-504 ◽  
Author(s):  
Sylke Winkler ◽  
Nicola Gscheidel ◽  
Michael Brand
Keyword(s):  
Model Organisms ◽  
Vertebrate Model
Sign in / Sign up

Export Citation Format

Share Document