Protocol for HSDFinder: Identifying, annotating, categorizing, and visualizing duplicated genes in eukaryotic genomes

AbstractThere is increasing evidence that some functionally related, co-expressed genes cluster within eukaryotic genomes. We present a novel pipeline that delineates such eukaryotic gene clusters. Using this tool for bread wheat, we uncovered 44 clusters of genes that are responsive to the fungal pathogen Fusarium graminearum. As expected, these Fusarium-responsive gene clusters (FRGCs) included metabolic gene clusters, many of which are associated with disease resistance, but hitherto not described for wheat. However, the majority of the FRGCs are non-metabolic, many of which contain clusters of paralogues, including those implicated in plant disease responses, such as glutathione transferases, MAP kinases, and germin-like proteins. 20 of the FRGCs encode nonhomologous, non-metabolic genes (including defence-related genes). One of these clusters includes the characterised Fusarium resistance orphan gene, TaFROG. Eight of the FRGCs map within 6 FHB resistance loci. One small QTL on chromosome 7D (4.7 Mb) encodes eight Fusarium-responsive genes, five of which are within a FRGC. This study provides a new tool to identify genomic regions enriched in genes responsive to specific traits of interest and applied herein it highlighted gene families, genetic loci and biological pathways of importance in the response of wheat to disease.

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Tc8, a Tourist-like Transposon in Caenorhabditis elegans

Genetics ◽

10.1093/genetics/158.3.1081 ◽

2001 ◽

Vol 158 (3) ◽

pp. 1081-1088 ◽

Cited By ~ 2

Author(s):

Quang Hien Le ◽

Kime Turcotte ◽

Thomas Bureau

Keyword(s):

Caenorhabditis Elegans ◽

Expressed Sequence Tags ◽

Large Family ◽

Insertion Sequences ◽

Normal Plant ◽

Nematode Caenorhabditis Elegans ◽

Plant Genomes ◽

Plant Genes ◽

Expressed Sequence ◽

Eukaryotic Genomes

Abstract Members of the Tourist family of miniature inverted-repeat transposable elements (MITEs) are very abundant among a wide variety of plants, are frequently found associated with normal plant genes, and thus are thought to be important players in the organization and evolution of plant genomes. In Arabidopsis, the recent discovery of a Tourist member harboring a putative transposase has shed new light on the mobility and evolution of MITEs. Here, we analyze a family of Tourist transposons endogenous to the genome of the nematode Caenorhabditis elegans (Bristol N2). One member of this large family is 7568 bp in length, harbors an ORF similar to the putative Tourist transposase from Arabidopsis, and is related to the IS5 family of bacterial insertion sequences (IS). Using database searches, we found expressed sequence tags (ESTs) similar to the putative Tourist transposases in plants, insects, and vertebrates. Taken together, our data suggest that Tourist-like and IS5-like transposons form a superfamily of potentially active elements ubiquitous to prokaryotic and eukaryotic genomes.

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Selective Constraints on Intron Evolution in Drosophila

Genetics ◽

10.1093/genetics/165.4.1843 ◽

2003 ◽

Vol 165 (4) ◽

pp. 1843-1851 ◽

Cited By ~ 4

Author(s):

John Parsch

Keyword(s):

Drosophila Melanogaster ◽

Natural Selection ◽

Common Ancestor ◽

Length Distribution ◽

Short Length ◽

Intron Length ◽

Intron Evolution ◽

Intron Size ◽

Duplicated Genes ◽

Selective Constraints

AbstractIntron sizes show an asymmetrical distribution in a number of organisms, with a large number of “short” introns clustered around a minimal intron length and a much broader distribution of longer introns. In Drosophila melanogaster, the short intron class is centered around 61 bp. The narrow length distribution suggests that natural selection may play a role in maintaining intron size. A comparison of 15 orthologous introns among species of the D. melanogaster subgroup indicates that, in general, short introns are not under greater DNA sequence or length constraints than long introns. There is a bias toward deletions in all introns (deletion/insertion ratio is 1.66), and the vast majority of indels are of short length (<10 bp). Indels occurring on the internal branches of the phylogenetic tree are significantly longer than those occurring on the terminal branches. These results are consistent with a compensatory model of intron length evolution in which slightly deleterious short deletions are frequently fixed within species by genetic drift, and relatively rare larger insertions that restore intron length are fixed by positive selection. A comparison of paralogous introns shared among duplicated genes suggests that length constraints differ between introns within the same gene. The janusA, janusB, and ocnus genes share two short introns derived from a common ancestor. The first of these introns shows significantly fewer indels than the second intron, although the two introns show a comparable number of substitutions. This indicates that intron-specific selective constraints have been maintained following gene duplication, which preceded the divergence of the D. melanogaster species subgroup.

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Islands of complex DNA are widespread in Drosophila centric heterochromatin.

Genetics ◽

10.1093/genetics/141.1.283 ◽

1995 ◽

Vol 141 (1) ◽

pp. 283-303

Author(s):

M H Le ◽

D Duricka ◽

G H Karpen

Keyword(s):

Dna Sequences ◽

Structure And Function ◽

Southern Analysis ◽

Cloning And Sequencing ◽

Pulsed Field ◽

Drosophila Heterochromatin ◽

And Function ◽

Heterochromatin Structure ◽

Derivatives Of ◽

Eukaryotic Genomes

Abstract Heterochromatin is a ubiquitous yet poorly understood component of multicellular eukaryotic genomes. Major gaps exist in our knowledge of the nature and overall organization of DNA sequences present in heterochromatin. We have investigated the molecular structure of the 1 Mb of centric heterochromatin in the Drosophila minichromosome Dp1187. A genetic screen of irradiated minichromosomes yielded rearranged derivatives of Dp1187 whose structures were determined by pulsed-field Southern analysis and PCR. Three Dp1187 deletion derivatives and an inversion had one breakpoint in the euchromatin and one in the heterochromatin, providing direct molecular access to previously inaccessible parts of the heterochromatin. End-probed pulsed-field restriction mapping revealed the presence of at least three "islands" of complex DNA, Tahiti, Moorea, and Bora Bora, constituting approximately one half of the Dp1187 heterochromatin. Pulsed-field Southern analysis demonstrated that Drosophila heterochromatin in general is composed of alternating blocks of complex DNA and simple satellite DNA. Cloning and sequencing of a small part of one island, Tahiti, demonstrated the presence of a retroposon. The implications of these findings to heterochromatin structure and function are discussed.

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CRISPR-Based Technologies for the Manipulation of Eukaryotic Genomes

Cell ◽

10.1016/j.cell.2017.04.005 ◽

2017 ◽

Vol 169 (3) ◽

pp. 559 ◽

Cited By ~ 91

Author(s):

Alexis C. Komor ◽

Ahmed H. Badran ◽

David R. Liu

Keyword(s):

Eukaryotic Genomes

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Transposable Elements and Teleost Migratory Behaviour

International Journal of Molecular Sciences ◽

10.3390/ijms22020602 ◽

2021 ◽

Vol 22 (2) ◽

pp. 602

Author(s):

Elisa Carotti ◽

Federica Carducci ◽

Adriana Canapa ◽

Marco Barucca ◽

Samuele Greco ◽

...

Keyword(s):

Transposable Elements ◽

Environmental Changes ◽

Chromosomal Rearrangements ◽

Quantitative Difference ◽

Regulatory Elements ◽

Phylogenetic Position ◽

Migratory Behaviour ◽

Relative Contribution ◽

Migratory Routes ◽

Eukaryotic Genomes

Transposable elements (TEs) represent a considerable fraction of eukaryotic genomes, thereby contributing to genome size, chromosomal rearrangements, and to the generation of new coding genes or regulatory elements. An increasing number of works have reported a link between the genomic abundance of TEs and the adaptation to specific environmental conditions. Diadromy represents a fascinating feature of fish, protagonists of migratory routes between marine and freshwater for reproduction. In this work, we investigated the genomes of 24 fish species, including 15 teleosts with a migratory behaviour. The expected higher relative abundance of DNA transposons in ray-finned fish compared with the other fish groups was not confirmed by the analysis of the dataset considered. The relative contribution of different TE types in migratory ray-finned species did not show clear differences between oceanodromous and potamodromous fish. On the contrary, a remarkable relationship between migratory behaviour and the quantitative difference reported for short interspersed nuclear (retro)elements (SINEs) emerged from the comparison between anadromous and catadromous species, independently from their phylogenetic position. This aspect is likely due to the substantial environmental changes faced by diadromous species during their migratory routes.

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OpenProt 2021: deeper functional annotation of the coding potential of eukaryotic genomes

Nucleic Acids Research ◽

10.1093/nar/gkaa1036 ◽

2020 ◽

Vol 49 (D1) ◽

pp. D380-D388 ◽

Cited By ~ 1

Author(s):

Marie A Brunet ◽

Jean-François Lucier ◽

Maxime Levesque ◽

Sébastien Leblanc ◽

Jean-Francois Jacques ◽

...

Keyword(s):

Confidence Score ◽

Ribosome Profiling ◽

Open Reading Frames ◽

Supporting Evidence ◽

Initial Release ◽

Ncbi Refseq ◽

Computational Resources ◽

Analysis Platform ◽

Eukaryotic Genomes ◽

Reading Frames

Abstract OpenProt (www.openprot.org) is the first proteogenomic resource supporting a polycistronic annotation model for eukaryotic genomes. It provides a deeper annotation of open reading frames (ORFs) while mining experimental data for supporting evidence using cutting-edge algorithms. This update presents the major improvements since the initial release of OpenProt. All species support recent NCBI RefSeq and Ensembl annotations, with changes in annotations being reported in OpenProt. Using the 131 ribosome profiling datasets re-analysed by OpenProt to date, non-AUG initiation starts are reported alongside a confidence score of the initiating codon. From the 177 mass spectrometry datasets re-analysed by OpenProt to date, the unicity of the detected peptides is controlled at each implementation. Furthermore, to guide the users, detectability statistics and protein relationships (isoforms) are now reported for each protein. Finally, to foster access to deeper ORF annotation independently of one’s bioinformatics skills or computational resources, OpenProt now offers a data analysis platform. Users can submit their dataset for analysis and receive the results from the analysis by OpenProt. All data on OpenProt are freely available and downloadable for each species, the release-based format ensuring a continuous access to the data. Thus, OpenProt enables a more comprehensive annotation of eukaryotic genomes and fosters functional proteomic discoveries.

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