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Kulak M, Komissarov A, Fillon V, Tsukanova K, Saifitdinova A, Galkina S. Genome organization of major tandem repeats and their specificity for heterochromatin of macro- and microchromosomes in Japanese quail. Genome 2022; 65:391-403. [PMID: 35776982 DOI: 10.1139/gen-2022-0012] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tandemly repeated DNAs form heterochromatic regions of chromosomes, including the vital centromeric chromatin. Despite the progress in new genomic technologies tandem repeats remain poorly deciphered and need targeted analysis in the species of interest. The Japanese quail is one of the highest-producing poultry species as well as a model organism. Its genome differs by a noticeable accumulation of heterochromatin, which led to an increase by 1/7 compared to the chicken genome size. Prominent heterochromatin blocks occupy the short arms of acrocentric macrochromosomes and of microchromosomes. We have applied de novo repeat finder approach to unassembled raw reads of the Japanese quail genome. We identified the 20 most common tandem repeats with the abundance >1 Mb, which represent about 4.8% of the genome. We found that tandem repeat CjapSAT primarily contribute to the centromeric regions of the macrochromosomes CJA1-8. Cjap31B together with previously characterized BglII make up centromere regions of microchromosomes and W chromosome. Other repeats populate heterochromatin of microchromosomal short arms in unequal proportions, as revealed by FISH. The Cjap84A, Cjap408A and CjapSAT repeat sequences show similarities with retrotransposon motifs. This suggests that retroelements may have played a crucial role in the distribution of repeats throughout the Japanese quail genome.
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Affiliation(s)
- Maria Kulak
- Saint Petersburg State University, Saint Petersburg, Russian Federation;
| | | | - Valerie Fillon
- INRA Toulouse-Occitanie, Castanet Tolosan, Occitanie, France;
| | - Kseniya Tsukanova
- Saint Petersburg State University, Saint Petersburg, Russian Federation;
| | - Alsu Saifitdinova
- Herzen State Pedagogical University of Russia, 104720, Saint Petersburg, Russian Federation;
| | - Svetlana Galkina
- Saint Petersburg State University, Saint Petersburg, Russian Federation;
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Báez M, Vaio M, Dreissig S, Schubert V, Houben A, Pedrosa-Harand A. Together But Different: The Subgenomes of the Bimodal Eleutherine Karyotypes Are Differentially Organized. FRONTIERS IN PLANT SCIENCE 2019; 10:1170. [PMID: 31649686 PMCID: PMC6791338 DOI: 10.3389/fpls.2019.01170] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 08/27/2019] [Indexed: 06/10/2023]
Abstract
Bimodal karyotypes are characterized by the presence of two sets of chromosomes of contrasting size. Eleutherine bulbosa (2n = 12) presents a bimodal karyotype with a large chromosome pair, which has a pericentric inversion in permanent heterozygosity with suppressed recombination, and five pairs of three to four times smaller chromosomes. Aiming to understand whether high copy number sequence composition differs between both chromosome sets, we investigated the repetitive DNA fraction of E. bulbosa and compared it to the chromosomal organization of the related Eleutherine latifolia species, not containing the pericentric inversion. We also compared the repetitive sequence proportions between the heteromorphic large chromosomes of E. bulbosa and between E. bulbosa and E. latifolia to understand the influence of the chromosome inversion on the dynamics of repetitive sequences. The most abundant repetitive families of the genome showed a similar chromosomal distribution in both homologs of the large pair and in both species, apparently not influenced by the species-specific inversions. The repeat families Ebusat1 and Ebusat4 are localized interstitially only on the large chromosome pair, while Ebusat2 is located in the centromeric region of all chromosomes. The four most abundant retrotransposon lineages are accumulated in the large chromosome pair. Replication timing and distribution of epigenetic and transcriptional marks differ between large and small chromosomes. The differential distribution of retroelements appears to be related to the bimodal condition and is not influenced by the nonrecombining chromosome inversions in these species. Thus, the large and small chromosome subgenomes of the bimodal Eleutherine karyotype are differentially organized and probably evolved by repetitive sequences accumulation on the large chromosome set.
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Affiliation(s)
- Mariana Báez
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Recife, Brazil
| | - Magdalena Vaio
- Laboratory of Genetics, Department of Plant Biology, College of Agronomy, University of the Republic, Montevideo, Uruguay
| | - Steven Dreissig
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Veit Schubert
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Andreas Houben
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Andrea Pedrosa-Harand
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Recife, Brazil
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Kolchanova S, Kliver S, Komissarov A, Dobrinin P, Tamazian G, Grigorev K, Wolfsberger WW, Majeske AJ, Velez-Valentin J, Valentin de la Rosa R, Paul-Murphy JR, Guzman DSM, Court MH, Rodriguez-Flores JL, Martínez-Cruzado JC, Oleksyk TK. Genomes of Three Closely Related Caribbean Amazons Provide Insight for Species History and Conservation. Genes (Basel) 2019; 10:E54. [PMID: 30654561 PMCID: PMC6356210 DOI: 10.3390/genes10010054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 12/13/2018] [Accepted: 01/08/2019] [Indexed: 11/17/2022] Open
Abstract
Islands have been used as model systems for studies of speciation and extinction since Darwin published his observations about finches found on the Galapagos. Amazon parrots inhabiting the Greater Antillean Islands represent a fascinating model of species diversification. Unfortunately, many of these birds are threatened as a result of human activity and some, like the Puerto Rican parrot, are now critically endangered. In this study we used a combination of de novo and reference-assisted assembly methods, integrating it with information obtained from related genomes to perform genome reconstruction of three amazon species. First, we used whole genome sequencing data to generate a new de novo genome assembly for the Puerto Rican parrot (Amazona vittata). We then improved the obtained assembly using transcriptome data from Amazona ventralis and used the resulting sequences as a reference to assemble the genomes Hispaniolan (A. ventralis) and Cuban (Amazona leucocephala) parrots. Finally, we, annotated genes and repetitive elements, estimated genome sizes and current levels of heterozygosity, built models of demographic history and provided interpretation of our findings in the context of parrot evolution in the Caribbean.
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Affiliation(s)
- Sofiia Kolchanova
- Department of Biology, University of Puerto Rico at Mayaguez, Mayaguez, PR 00680, USA.
- Department of Biology, University of Konstanz, 78464 Konstanz, Germany.
- Theodosius Dobzhansky Center for Genome Bioinformatics, St. Petersburg State University, 199034 St. Petersburg, Russia.
| | - Sergei Kliver
- Theodosius Dobzhansky Center for Genome Bioinformatics, St. Petersburg State University, 199034 St. Petersburg, Russia.
| | - Aleksei Komissarov
- Theodosius Dobzhansky Center for Genome Bioinformatics, St. Petersburg State University, 199034 St. Petersburg, Russia.
| | - Pavel Dobrinin
- Theodosius Dobzhansky Center for Genome Bioinformatics, St. Petersburg State University, 199034 St. Petersburg, Russia.
| | - Gaik Tamazian
- Theodosius Dobzhansky Center for Genome Bioinformatics, St. Petersburg State University, 199034 St. Petersburg, Russia.
| | - Kirill Grigorev
- Department of Biology, University of Puerto Rico at Mayaguez, Mayaguez, PR 00680, USA.
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10021, USA.
| | - Walter W Wolfsberger
- Department of Biology, University of Puerto Rico at Mayaguez, Mayaguez, PR 00680, USA.
- Department of Biological Sciences, Oakland University, 118 Library Drive, Rochester, MI 48309, USA.
- Department of Biological Sciences, Uzhhorod National University, 88000 Uzhhorod, Ukraine.
| | - Audrey J Majeske
- Department of Biology, University of Puerto Rico at Mayaguez, Mayaguez, PR 00680, USA.
- Beaumont BioBank, William Beaumont Hospital, Royal Oak, MI 48073, USA.
| | - Jafet Velez-Valentin
- Conservation Program of the Puerto Rican Parrot, U.S. Fish and Wildlife Service, Rio Grande, PR 00745, USA.
| | - Ricardo Valentin de la Rosa
- The Recovery Program of the Puerto Rican Parrot at the Rio Abajo State Forest, Departamento de Recursos Naturales y Ambientales de Puerto Rico, Arecibo, PR 00613, USA.
| | - Joanne R Paul-Murphy
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California Davis, Davis, CA 95616, USA.
| | - David Sanchez-Migallon Guzman
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California Davis, Davis, CA 95616, USA.
| | - Michael H Court
- Program in Individualized Medicine (PrIMe), Pharmacogenomics Laboratory, Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, 100 Grimes Way, Pullman, WA 99164, USA.
| | | | | | - Taras K Oleksyk
- Department of Biology, University of Puerto Rico at Mayaguez, Mayaguez, PR 00680, USA.
- Department of Biological Sciences, Oakland University, 118 Library Drive, Rochester, MI 48309, USA.
- Department of Biological Sciences, Uzhhorod National University, 88000 Uzhhorod, Ukraine.
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Bertocchi NA, de Oliveira TD, Del Valle Garnero A, Coan RLB, Gunski RJ, Martins C, Torres FP. Distribution of CR1-like transposable element in woodpeckers (Aves Piciformes): Z sex chromosomes can act as a refuge for transposable elements. Chromosome Res 2018; 26:333-343. [PMID: 30499043 DOI: 10.1007/s10577-018-9592-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 10/14/2018] [Accepted: 11/13/2018] [Indexed: 11/28/2022]
Abstract
Birds have relatively few repetitive sequences compared to other groups of vertebrates; however, the members of order Piciformes (woodpeckers) have more of these sequences, composed mainly of transposable elements (TE). The TE most often found in birds is a retrotransposon chicken repeat 1 (CR1). Piciformes lineages were subjected to an expansion of the CR1 elements, carrying a larger fraction of transposable elements. This study compared patterns of chromosome distribution among five bird species, through chromosome mapping of the CR1 sequence and reconstructed their phylogenetic tree. We analyzed several members of Piciformes (Colaptes campestris, Colaptes melanochloros, Melanerpes candidus, and Veniliornis spilogaster), as well as Galliformes (Gallus gallus). Gallus gallus is the species with which most genomic and hence cytogenetic studies have been performed. The results showed that CR1 sequences are a monophyletic group and do not depend on their hosts. All species analyzed showed a hybridization signal by fluorescence in situ hybridization (FISH). In all species, the chromosomal distribution of CR1 was not restricted to heterochromatin regions in the macrochromosomes, principally pair 1 and the Z sex chromosome. Accumulation in the Z sex chromosomes can serve as a refuge for transposable elements. These results highlight the importance of transposable elements in host genomes and karyotype evolution.
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Affiliation(s)
- Natasha Avila Bertocchi
- Programa de Pós-graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, 91501-970, Brazil.
| | - Thays Duarte de Oliveira
- Programa de Pós-graduação em Biologia Animal, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, 91540-000, Brazil
| | - Analía Del Valle Garnero
- Programa de Pós-graduação em Ciências Biológicas, Universidade Federal do Pampa (Unipampa), São Gabriel, Rio Grande do Sul, 97300-000, Brazil.,Laboratório de Diversidade Genética Animal, Universidade Federal do Pampa (Unipampa), São Gabriel, Rio Grande do Sul, 97300-000, Brazil
| | - Rafael Luiz Buogo Coan
- Departamento de Morfologia, Laboratório Genômica Integrativa, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo, 18618-689, Brazil
| | - Ricardo José Gunski
- Programa de Pós-graduação em Ciências Biológicas, Universidade Federal do Pampa (Unipampa), São Gabriel, Rio Grande do Sul, 97300-000, Brazil.,Laboratório de Diversidade Genética Animal, Universidade Federal do Pampa (Unipampa), São Gabriel, Rio Grande do Sul, 97300-000, Brazil
| | - Cesar Martins
- Departamento de Morfologia, Laboratório Genômica Integrativa, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo, 18618-689, Brazil
| | - Fabiano Pimentel Torres
- Programa de Pós-graduação em Ciências Biológicas, Universidade Federal do Pampa (Unipampa), São Gabriel, Rio Grande do Sul, 97300-000, Brazil.,Laboratório de Diversidade Genética Animal, Universidade Federal do Pampa (Unipampa), São Gabriel, Rio Grande do Sul, 97300-000, Brazil
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Clinton M, Nandi S, Zhao D, Olson S, Peterson P, Burdon T, McBride D. Real-Time Sexing of Chicken Embryos and Compatibility with in ovo Protocols. Sex Dev 2016; 10:210-216. [PMID: 27559746 DOI: 10.1159/000448502] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Indexed: 11/19/2022] Open
Abstract
The chicken embryo is an established model system for studying early vertebrate development. One of the major advantages of this model is the facility to perform manipulations in ovo and then continue incubation and observe the effects on embryonic development. However, in common with other vertebrate models, there is a tendency to disregard the sex of the experimental chicken embryos, and this can lead to erroneous conclusions, a lack of reproducibility, and wasted efforts. That this neglect is untenable is emphasised by the recent demonstration that avian cells and tissues have an inherent sex identity and that male and female tissues respond differently to the same stimulus. These sexually dimorphic characteristics dictate that analyses and manipulations involving chicken embryos should always be performed using tissues/embryos of known sex. Current sexing protocols are unsuitable in many instances because of the time constraints imposed by most in ovo procedures. To address this lack, we have developed a real-time chicken sexing assay that is compatible with in ovo manipulations, reduces the number of embryos required, and conserves resources.
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Affiliation(s)
- Michael Clinton
- Developmental Biology, The Roslin Institute and R(D)SVS, University of Edinburgh, Roslin, UK
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Hen G, Yosefi S, Shinder D, Or A, Mygdal S, Condiotti R, Galun E, Bor A, Sela-Donenfeld D, Friedman-Einat M. Gene transfer to chicks using lentiviral vectors administered via the embryonic chorioallantoic membrane. PLoS One 2012; 7:e36531. [PMID: 22606269 PMCID: PMC3350527 DOI: 10.1371/journal.pone.0036531] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Accepted: 04/03/2012] [Indexed: 12/22/2022] Open
Abstract
The lack of affordable techniques for gene transfer in birds has inhibited the advancement of molecular studies in avian species. Here we demonstrate a new approach for introducing genes into chicken somatic tissues by administration of a lentiviral vector, derived from the feline immunodeficiency virus (FIV), into the chorioallantoic membrane (CAM) of chick embryos on embryonic day 11. The FIV-derived vectors carried yellow fluorescent protein (YFP) or recombinant alpha-melanocyte-stimulating hormone (α-MSH) genes, driven by the cytomegalovirus (CMV) promoter. Transgene expression, detected in chicks 2 days after hatch by quantitative real-time PCR, was mostly observed in the liver and spleen. Lower expression levels were also detected in the brain, kidney, heart and breast muscle. Immunofluorescence and flow cytometry analyses confirmed transgene expression in chick tissues at the protein level, demonstrating a transduction efficiency of ∼0.46% of liver cells. Integration of the viral vector into the chicken genome was demonstrated using genomic repetitive (CR1)-PCR amplification. Viability and stability of the transduced cells was confirmed using terminal deoxynucleotidyl transferase (dUTP) nick end labeling (TUNEL) assay, immunostaining with anti-proliferating cell nuclear antigen (anti-PCNA), and detection of transgene expression 51 days post transduction. Our approach led to only 9% drop in hatching efficiency compared to non-injected embryos, and all of the hatched chicks expressed the transgenes. We suggest that the transduction efficiency of FIV vectors combined with the accessibility of the CAM vasculature as a delivery route comprise a new powerful and practical approach for gene delivery into somatic tissues of chickens. Most relevant is the efficient transduction of the liver, which specializes in the production and secretion of proteins, thereby providing an optimal target for prolonged study of secreted hormones and peptides.
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Affiliation(s)
- Gideon Hen
- Ministry of Agriculture, Volcani Center, Bet-Dagan, Israel
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food & Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Sara Yosefi
- Ministry of Agriculture, Volcani Center, Bet-Dagan, Israel
| | - Dmitry Shinder
- Ministry of Agriculture, Volcani Center, Bet-Dagan, Israel
| | - Adi Or
- Ministry of Agriculture, Volcani Center, Bet-Dagan, Israel
| | - Sivan Mygdal
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food & Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Reba Condiotti
- Goldyne Savad Institute of Gene Therapy, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Eithan Galun
- Goldyne Savad Institute of Gene Therapy, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Amir Bor
- Ministry of Agriculture, Volcani Center, Bet-Dagan, Israel
| | - Dalit Sela-Donenfeld
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food & Environment, The Hebrew University of Jerusalem, Rehovot, Israel
- * E-mail: (DSD); (MFE)
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Janes DE, Organ CL, Fujita MK, Shedlock AM, Edwards SV. Genome evolution in Reptilia, the sister group of mammals. Annu Rev Genomics Hum Genet 2010; 11:239-64. [PMID: 20590429 DOI: 10.1146/annurev-genom-082509-141646] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The genomes of birds and nonavian reptiles (Reptilia) are critical for understanding genome evolution in mammals and amniotes generally. Despite decades of study at the chromosomal and single-gene levels, and the evidence for great diversity in genome size, karyotype, and sex chromosome diversity, reptile genomes are virtually unknown in the comparative genomics era. The recent sequencing of the chicken and zebra finch genomes, in conjunction with genome scans and the online publication of the Anolis lizard genome, has begun to clarify the events leading from an ancestral amniote genome--predicted to be large and to possess a diverse repeat landscape on par with mammals and a birdlike sex chromosome system--to the small and highly streamlined genomes of birds. Reptilia exhibit a wide range of evolutionary rates of different subgenomes and, from isochores to mitochondrial DNA, provide a critical contrast to the genomic paradigms established in mammals.
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Affiliation(s)
- Daniel E Janes
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
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Soattin M, Barcaccia G, Dalvit C, Cassandro M, Bittante G. Genomic DNA fingerprinting of indigenous chicken breeds with molecular markers designed on interspersed repeats. Hereditas 2009; 146:183-97. [DOI: 10.1111/j.1601-5223.2009.02106.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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The early apoptotic DNA fragmentation targets a small number of specific open chromatin regions. PLoS One 2009; 4:e5010. [PMID: 19347039 PMCID: PMC2661134 DOI: 10.1371/journal.pone.0005010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Accepted: 03/02/2009] [Indexed: 11/19/2022] Open
Abstract
We report here that early apoptotic DNA fragmentation, as obtained by using an entirely new approach, is the result of an attack at a small number of specific open chromatin regions of interphase nuclei. This was demonstrated as follows: (i) chicken liver was excised and kept in sterile tubes for 1 to 3 hours at 37 degrees C; (ii) this induced apoptosis (possibly because of oxygen deprivation), as shown by the electrophoretic nucleosomal ladder produced by DNA preparations; (iii) low molecular-weight DNA fragments (approximately 200 bp) were cloned, sequenced, and shown to derive predominantly from genes and surrounding 100 kb regions; (iv) a few hundred cuts were produced, very often involving the same chromosomal sites; (v) at comparable DNA degradation levels, micrococcal nuclease (MNase) also showed a general preference for genes and surrounding regions, but MNase cuts were located at sites that were quite distinct from, and less specific than, those cut by apoptosis. In conclusion, the approach presented here, which is the mildest and least intrusive approach, identifies a preferred accessibility landscape in interphase chromatin.
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St John J, Quinn TW. Recent CR1 non-LTR retrotransposon activity in coscoroba reveals an insertion site preference. BMC Genomics 2008; 9:567. [PMID: 19038033 PMCID: PMC2612034 DOI: 10.1186/1471-2164-9-567] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Accepted: 11/27/2008] [Indexed: 11/17/2022] Open
Abstract
Background Chicken repeat 1 (CR1) is a taxonomically widespread non-LTR retrotransposon. Insertion site bias, or lack thereof, has not been demonstrated for CR1. Recent CR1 retrotranspositions were used to examine flanking regions for GC content and nucleotide bias at the insertion site. Results Elucidation of the exact octomer repeat sequence (TTCTGTGA) allowed for the identification of younger insertion events. The number of octomer repeats associated with a CR1 element increases after insertion with CR1s having one octomer being youngest. These young CR1s are flanked by regions of low GC content (38%). Furthermore, a bias for specific bases within the first four positions at the site of insertion was revealed. Conclusion This study focused on those loci where the insertion event has been most recent, as this would tend to minimize noise introduced by post-integration mutational events. Our data suggest that CR1 is not inserting into regions of higher GC content within the coscoroba genome; but rather, preferentially inserting into regions of lower GC content. Furthermore, there appears to be a base preference (TTCT) for the insertion site. The results of this study increase the current level of understanding regarding the elusive CR1 non-LTR retrotransposon.
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Affiliation(s)
- Judy St John
- Rocky Mountain Center for Conservation Genetics and Systematics, Division of Natural Sciences and Mathematics, University of Denver, Denver, Colorado, USA.
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