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Matoulek D, Borůvková V, Ocalewicz K, Symonová R. GC and Repeats Profiling along Chromosomes-The Future of Fish Compositional Cytogenomics. Genes (Basel) 2020; 12:50. [PMID: 33396302 PMCID: PMC7823971 DOI: 10.3390/genes12010050] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 12/14/2022] Open
Abstract
The study of fish cytogenetics has been impeded by the inability to produce G-bands that could assign chromosomes to their homologous pairs. Thus, the majority of karyotypes published have been estimated based on morphological similarities of chromosomes. The reason why chromosome G-banding does not work in fish remains elusive. However, the recent increase in the number of fish genomes assembled to the chromosome level provides a way to analyse this issue. We have developed a Python tool to visualize and quantify GC percentage (GC%) of both repeats and unique DNA along chromosomes using a non-overlapping sliding window approach. Our tool profiles GC% and simultaneously plots the proportion of repeats (rep%) in a color scale (or vice versa). Hence, it is possible to assess the contribution of repeats to the total GC%. The main differences are the GC% of repeats homogenizing the overall GC% along fish chromosomes and a greater range of GC% scattered along fish chromosomes. This may explain the inability to produce G-banding in fish. We also show an occasional banding pattern along the chromosomes in some fish that probably cannot be detected with traditional qualitative cytogenetic methods.
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Affiliation(s)
- Dominik Matoulek
- Faculty of Science, University of Hradec Kralove, 500 03 Hradec Králové, Czech Republic; (D.M.); (V.B.)
| | - Veronika Borůvková
- Faculty of Science, University of Hradec Kralove, 500 03 Hradec Králové, Czech Republic; (D.M.); (V.B.)
| | - Konrad Ocalewicz
- Department of Marine Biology and Ecology, Institute of Oceanography, Faculty of Oceanography and Geography, University of Gdansk, 80-309 Gdansk, Poland;
| | - Radka Symonová
- Department of Bioinformatics, Wissenschaftszentrum Weihenstephan, Technische Universität München, 80333 Freising, Germany
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Kim C, Sung S, Kim J, Lee J. Repair and Reconstruction of Telomeric and Subtelomeric Regions and Genesis of New Telomeres: Implications for Chromosome Evolution. Bioessays 2020; 42:e1900177. [PMID: 32236965 DOI: 10.1002/bies.201900177] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 02/20/2020] [Indexed: 12/12/2022]
Abstract
DNA damage repair within telomeres are suppressed to maintain the integrity of linear chromosomes, but the accidental activation of repairs can lead to genome instability. This review develops the concept that mechanisms to repair DNA damage in telomeres contribute to genetic variability and karyotype evolution, rather than catastrophe. Spontaneous breaks in telomeres can be repaired by telomerase, but in some cases DNA repair pathways are activated, and can cause chromosomal rearrangements or fusions. The resultant changes can also affect subtelomeric regions that are adjacent to telomeres. Subtelomeres are actively involved in such chromosomal changes, and are therefore the most variable regions in the genome. The case of Caenorhabditis elegans in the context of changes of subtelomeric structures revealed by long-read sequencing is also discussed. Theoretical and methodological issues covered in this review will help to explore the mechanism of chromosome evolution by reconstruction of chromosomal ends in nature.
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Affiliation(s)
- Chuna Kim
- Department of Biological Sciences, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08827, Korea.,Aging Research Institute, Korea Research Institute of Bioscience and Biotechnology, Gwahak-ro 125, Daejeon, 34141, Korea
| | - Sanghyun Sung
- Department of Biological Sciences, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08827, Korea
| | - Jun Kim
- Department of Biological Sciences, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08827, Korea
| | - Junho Lee
- Department of Biological Sciences, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08827, Korea
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Auvinet J, Graça P, Dettai A, Amores A, Postlethwait JH, Detrich HW, Ozouf-Costaz C, Coriton O, Higuet D. Multiple independent chromosomal fusions accompanied the radiation of the Antarctic teleost genus Trematomus (Notothenioidei:Nototheniidae). BMC Evol Biol 2020; 20:39. [PMID: 32192426 PMCID: PMC7082932 DOI: 10.1186/s12862-020-1600-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 03/03/2020] [Indexed: 12/20/2022] Open
Abstract
Background Chromosomal rearrangements are thought to be an important driving force underlying lineage diversification, but their link to speciation continues to be debated. Antarctic teleost fish of the family Nototheniidae (Notothenioidei) diversified in a changing environmental context, which led to ecological, morphological, and genetic differentiation among populations. In addition, extensive chromosomal repatterning accompanied species divergence in several clades. The most striking karyotypic changes involved the recent species radiation (about 10 My) of the genus Trematomus, with chromosomal pair numbers ranging between 29 and 12. These dramatic reductions in chromosome number resulted mostly from large-scale chromosome fusions. Multiple centric and/or tandem fusions have been hypothesized in at least seven of the twelve recognized Trematomus species. To reconstruct their evolutionary history, we employed comparative cytogenomics (BAC-FISH and chromosome painting) to reveal patterns of interspecific chromosomal orthologies across several notothenioid clades. Results We defined orthologous chromosomal segments of reference, termed Structural Units (SUs). SUs were identified in a total of 18 notothenioid species. We demonstrated for the first time that SUs were strongly conserved across every specimen examined, with chromosomal syntenies highlighting a paucity of intrachromosomal macro-rearrangements. Multiple independent fusions of these SUs were inferred in the Trematomus species, in contrast to the shared SU fusions in species of the sister lineage Notothenia. Conclusions The SU segments were defined units of chromosomal rearrangement in the entire family Nototheiidae, which diverged from the other notothenioid families 20 My ago. Some of the identified chromosomal syntenies within the SUs were even conserved in their closest relatives, the family Eleginopsidae. Comparing the timing of acquisition of the fusions in the closely related genera Notothenia and Trematomus of the nototheniid species family, we conclude that they exhibit distinct chromosomal evolutionary histories, which may be relevant to different speciation scenarios.
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Affiliation(s)
- Juliette Auvinet
- Sorbonne Université, CNRS, Université des Antilles, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005, Paris, France. .,Institut de Systématique, Evolution, Biodiversité (ISYEB) - Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 43, rue Cuvier, 75231, Paris Cedex 05, France. .,Department of Marine and Environmental Sciences, Marine Science Center, Northeastern University, Nahant, MA, 01908, USA.
| | - Paula Graça
- Sorbonne Université, CNRS, Université des Antilles, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005, Paris, France.,Institut de Systématique, Evolution, Biodiversité (ISYEB) - Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 43, rue Cuvier, 75231, Paris Cedex 05, France
| | - Agnès Dettai
- Institut de Systématique, Evolution, Biodiversité (ISYEB) - Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 43, rue Cuvier, 75231, Paris Cedex 05, France
| | - Angel Amores
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR, 97403, USA
| | - John H Postlethwait
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR, 97403, USA
| | - H William Detrich
- Department of Marine and Environmental Sciences, Marine Science Center, Northeastern University, Nahant, MA, 01908, USA
| | - Catherine Ozouf-Costaz
- Sorbonne Université, CNRS, Université des Antilles, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005, Paris, France
| | - Olivier Coriton
- Institut National de Recherche pour l'agriculture, l'alimentation et l'environnement, INRAE, UMR1349 IGEPP, Molecular cytogenetics Platform, BP35327, F-35653, Le Rheu Cedex, France
| | - Dominique Higuet
- Sorbonne Université, CNRS, Université des Antilles, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005, Paris, France. .,Institut de Systématique, Evolution, Biodiversité (ISYEB) - Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 43, rue Cuvier, 75231, Paris Cedex 05, France.
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Shi Y, Zhou Z, Liu B, Kong S, Chen B, Bai H, Li L, Pu F, Xu P. Construction of a High-Density Genetic Linkage Map and QTL Mapping for Growth-Related Traits in Takifugu bimaculatus. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2020; 22:130-144. [PMID: 31900733 DOI: 10.1007/s10126-019-09938-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 12/03/2019] [Indexed: 06/10/2023]
Abstract
Takifugu bimaculatus is a euryhaline species, distributed ranging from the southern Yellow Sea to the South China Sea. Their tolerance to a wide range of salinity and temperature, coupled with a desirable firm texture, makes T. bimaculatus a strong candidate for Takifugu aquaculture in subtropics areas. Due to the increasing demand in markets and emerging of the Takifugu aquaculture industry, close attention has been paid to improvement on the T. bimaculatus production. In aquaculture, the great effort has been put into marker-assisted selective breeding, and efficient improvement was realized. However, few genetic resources on T. bimaculatus are provided so far. Aiming at understanding the genetic basis underlying important economic growth traits, facilitating genetic improvement and enriching the genetic resource in T. bimaculatus, we constructed the first genetic linkage map for T. bimaculatus via double digestion restriction-site association DNA sequencing and conducted quantitative traits locus (QTL) mapping for growth-related traits. The map comprised 1976 single nucleotide polymorphism markers distributed on 22 linkage groups (LG), with a total genetic distance of 2039.74 cM. Based on the linkage map, a chromosome-level assembly was constructed whereby we carried out comparative genomics analysis, verifying the high accuracy on contigs ordering of the linkage map. On the other hand, 18 QTLs associated with growth traits were detected on LG6, LG7, LG8, LG10, LG20, and LG21 with phenotypical variance ranging from 15.1 to 56.4%. Candidate genes participating in cartilage development, fat accumulation, and other growth-related regulation activities were identified from these QTLs, including col11a1, foxa2, and thrap3. The linkage map provided a solid foundation for chromosomes assembly and refinement. QTLs reported here unraveled the genomic architecture of some growth traits, which will advance the investigation of aquaculture breeding efforts in T. bimaculatus.
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Affiliation(s)
- Yue Shi
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Zhixiong Zhou
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Bo Liu
- Fisheries Research Institute of Fujian, Xiamen, China
| | - Shengnan Kong
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Baohua Chen
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Huaqiang Bai
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Leibin Li
- Fisheries Research Institute of Fujian, Xiamen, China
| | - Fei Pu
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Peng Xu
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.
- Fujian Key Laboratory of Genetics and Breeding of Marine Organisms, Xiamen University, Xiamen, China.
- Shenzhen Research Institute of Xiamen University, Shenzhen, China.
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Zhang X, Mizukoshi M, Zhang H, Tan E, Igarashi Y, Suzuki Y, Mitsuyama S, Kinoshita S, Saito K, Watabe S, Asakawa S. Ultrahigh-Density Linkage Map Construction Using Low-Coverage Whole-Genome Sequencing of a Doubled Haploid Population: Case Study of Torafugu (Takifugu rubripes). Genes (Basel) 2018; 9:genes9030120. [PMID: 29495372 PMCID: PMC5867841 DOI: 10.3390/genes9030120] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 02/15/2018] [Accepted: 02/20/2018] [Indexed: 11/16/2022] Open
Abstract
Next-generation sequencing enables genome-wide genotyping of a large population and further facilitates the construction of a genetic linkage map. Low-coverage whole-genome sequencing has been employed for genetic linkage map construction in several species. However, this strategy generally requires available high-quality reference genomes and/or designed inbred pedigree lines, which restrict the scope of application for non-model and unsequenced species. Here, using torafugu (Takifugu rubripes) as a test model, we propose a new strategy for ultrahigh-density genetic linkage map construction using low-coverage whole-genome sequencing of a haploid/doubled haploid (H/DH) population without above requirements. Low-coverage (≈1×) whole-genome sequencing data of 165 DH individuals were used for de novo assembly and further performed single nucleotide polymorphisms (SNPs) calling, resulting in the identification of 1,070,601 SNPs. Based on SNP genotypes and de novo assembly, genotypes were associated with short DNA segments and an ultrahigh-density linkage map was constructed containing information of 802,277 SNPs in 3090 unique positions. Comparative analyses showed near-perfect concordance between the present linkage map and the latest published torafugu genome (FUGU5). This strategy would facilitate ultrahigh-density linkage map construction in various sexually reproducing organisms for which H/DH populations can be generated.
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Affiliation(s)
- Xiang Zhang
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
| | - Misaki Mizukoshi
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
| | - Hong Zhang
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
| | - Engkong Tan
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
| | - Yoji Igarashi
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
| | - Yutaka Suzuki
- Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan.
| | - Susumu Mitsuyama
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
| | - Shigeharu Kinoshita
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
| | - Kazuyoshi Saito
- Akita Prefectural Fisheries Promotion Center, Oga, Akita 010-0531, Japan.
| | - Shugo Watabe
- School of Marine Bioscience, Kitasato University, Sagamihara, Kanagawa 252-0373, Japan.
| | - Shuichi Asakawa
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
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Cold Fusion: Massive Karyotype Evolution in the Antarctic Bullhead Notothen Notothenia coriiceps. G3-GENES GENOMES GENETICS 2017; 7:2195-2207. [PMID: 28576775 PMCID: PMC5498148 DOI: 10.1534/g3.117.040063] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Half of all vertebrate species share a series of chromosome fusions that preceded the teleost genome duplication (TGD), but we do not understand the causative evolutionary mechanisms. The "Robertsonian-translocation hypothesis" suggests a regular fusion of each ancestral acro- or telocentric chromosome to just one other by centromere fusions, thus halving the karyotype. An alternative "genome-stirring hypothesis" posits haphazard and repeated fusions, inversions, and reciprocal and nonreciprocal translocations. To study large-scale karyotype reduction, we investigated the decrease of chromosome numbers in Antarctic notothenioid fish. Most notothenioids have 24 haploid chromosomes, but bullhead notothen (Notothenia coriiceps) has 11. To understand mechanisms, we made a RAD-tag meiotic map with ∼10,000 polymorphic markers. Comparative genomics aligned about a thousand orthologs of platyfish and stickleback genes along bullhead chromosomes. Results revealed that 9 of 11 bullhead chromosomes arose by fusion of just two ancestral chromosomes and two others by fusion of three ancestral chromosomes. All markers from each ancestral chromosome remained contiguous, implying no inversions across fusion borders. Karyotype comparisons support a history of: (1) Robertsonian fusions of 22 ancestral chromosomes in pairs to yield 11 fused plus two small unfused chromosomes, like N. angustata; (2) fusion of one of the remaining two ancestral chromosomes to a preexisting fused pair, giving 12 chromosomes like N. rossii; and (3) fusion of the remaining ancestral chromosome to another fused pair, giving 11 chromosomes in N. coriiceps These results raise the question of what selective forces promoted the systematic fusion of chromosomes in pairs and the suppression of pericentric inversions in this lineage, and provide a model for chromosome fusions in stem teleosts.
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Condensin, master organizer of the genome. Chromosome Res 2017; 25:61-76. [PMID: 28181049 DOI: 10.1007/s10577-017-9553-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 12/19/2016] [Accepted: 01/23/2017] [Indexed: 02/06/2023]
Abstract
A fundamental requirement in nature is for a cell to correctly package and divide its replicated genome. Condensin is a mechanical multisubunit complex critical to this process. Condensin uses ATP to power conformational changes in DNA to enable to correct DNA compaction, organization, and segregation of DNA from the simplest bacteria to humans. The highly conserved nature of the condensin complex and the structural similarities it shares with the related cohesin complex have provided important clues as to how it functions in cells. The fundamental requirement for condensin in mitosis and meiosis is well established, yet the precise mechanism of action is still an open question. Mutation or removal of condensin subunits across a range of species disrupts orderly chromosome condensation leading to errors in chromosome segregation and likely death of the cell. There are divergences in function across species for condensin. Once considered to function solely in mitosis and meiosis, an accumulating body of evidence suggests that condensin has key roles in also regulating the interphase genome. This review will examine how condensin organizes our genomes, explain where and how it binds the genome at a mechanical level, and highlight controversies and future directions as the complex continues to fascinate and baffle biologists.
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Abstract
The revolution in molecular techniques over the last 30 years detracted from many traditional cytological techniques for examining basic biological problems. One of these casualties is the preparation of karyotypes and analysis of chromosomal structure, behaviour, and variation. Recent technology permitting the full sequencing of organisms has highlighted (but does not replace) the importance of understanding chromosomal constitution and karyotype structure, which underpin genome organisation. This chapter provides simple and straightforward protocols for the preparation of chromosome spreads from animals, and more advanced techniques for cell culture and chromosomal banding and hybridisation.
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Affiliation(s)
- David M Rowell
- Department of Evolution, Ecology and Genetics, Research School of Biology, Australian National University, Canberra, ACT, Australia.
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de Lima LCB, Martinez PA, Molina WF. Cytogenetic characterization of three Balistoidea fish species from the Atlantic with inferences on chromosomal evolution in the families Monacanthidae and Balistidae. COMPARATIVE CYTOGENETICS 2011; 5:61-69. [PMID: 24260619 PMCID: PMC3833730 DOI: 10.3897/compcytogen.v5i1.1141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Accepted: 03/23/2010] [Indexed: 06/02/2023]
Abstract
The Tetraodontiformes are the most derived group of teleostean fish. Among other apomorphies, they are characterized by a high degree of fusions or significant bone loss in the head and body. In the early phylogenetic proposals presented for this order, the families Balistidae and Monacanthidae have been unanimously considered to be closely related. Although they have moderate species diversity, they are scarcely known in cytogenetic aspect and chromosomal pattern comparisons between these groups have yet to be established. The species Cantherhines macrocerus (Hollard,1853), Cantherhines pullus (Ranzani, 1842) (Monacanthidae) and Melichthys niger (Bloch, 1786) (Balistidae) were cytogenetically analyzed using conventional (Ag-impregnation, C-banding, CMA3- and DAPI-fluorescence) and molecular (FISH with an 18S rDNA probe) cytogenetic protocols. The karyotypes of all three species were very similar possessing diploid chromosome numbers 2n = 40 and composed exclusively of acrocentric chromosomes. Single NOR-bearing pair as well as positive heterochromatic blocks at pericentromeric regions were identified in the karyotypes of the three species studied. NOR-bearing sites were positively labeled after Ag-impregnation, C-banding, CMA3-fluorescence and FISH with an 18S rDNA probe but were negative after DAPI-fluorescence. Such remarkable shared conspicuous chromosomal characters corroborate either close phylogenetic relationship of these families, previously established by morphological and molecular data, or rather conservative nature of karyotype differentiation processes. The later hypothesis, however, appears less probable due to centric or in tandem fusions documented for another Balistoidea species.
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Affiliation(s)
- Lorena Corina Bezerra de Lima
- />Department of Cell Biology and Genetics, Centro de Biociências, Universidade Federal do io Grande do Norte, Campus Universitário, 59078 – 970 Natal, RN, Brazil
| | - Pablo Ariel Martinez
- />Department of Cell Biology and Genetics, Centro de Biociências, Universidade Federal do io Grande do Norte, Campus Universitário, 59078 – 970 Natal, RN, Brazil
| | - Wagner Franco Molina
- />Department of Cell Biology and Genetics, Centro de Biociências, Universidade Federal do io Grande do Norte, Campus Universitário, 59078 – 970 Natal, RN, Brazil
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Sarropoulou E, Fernandes JMO. Comparative genomics in teleost species: Knowledge transfer by linking the genomes of model and non-model fish species. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2010; 6:92-102. [PMID: 20961822 DOI: 10.1016/j.cbd.2010.09.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2010] [Revised: 09/15/2010] [Accepted: 09/15/2010] [Indexed: 12/14/2022]
Abstract
Comparative genomics is a powerful tool to transfer knowledge coming from model fish species to non-model fish species of economic or/and evolutionary interest. Such transfer is of importance as functional studies either are difficult to perform with most non-model species. The first comparative map constructed using the human and the chimpanzee genome allowed the identification of putative orthologues. Although comparative mapping in teleosts is still in its infancy, five model teleost genomes from different orders have been fully sequenced to date and the sequencing of several commercially important species are also underway or near completion. The accessibility of these whole genome sequences and rapid developments in genomics of fish species are paving the way towards new and valuable research in comparative genetics and genomics. With the accumulation of information in model species, the genetic and genomic characterization of non-model, but economically, physiologically or evolutionary important species is now feasible. Furthermore, comparison of low coverage gene maps of non-model fish species against fully sequenced fish species will enhance the efficiency of candidate gene identification projected for quantitative trait loci (QTL) scans for traits of special interest.
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Affiliation(s)
- Elena Sarropoulou
- Institute of Marine Biology and Genetics, Hellenic Centre for Marine Research, Crete, Greece.
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Watson CA, Hill JE, Graves JS, Wood AL, Kilgore KH. Use of a novel induced spawning technique for the first reported captive spawning of Tetraodon nigroviridis. Mar Genomics 2009; 2:143-6. [PMID: 21798183 DOI: 10.1016/j.margen.2009.04.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Revised: 04/09/2009] [Accepted: 04/17/2009] [Indexed: 11/26/2022]
Abstract
The spotted green pufferfish (Tetraodon nigroviridis) is an important genetics model animal due to its small, well-mapped genome. However, only wild-caught juveniles and adults are available to researchers. A lack of gametes, fertilized eggs, developing embryos, and other early life stages hampers development of the full potential of T. nigroviridis as a model research species. We report on successful spawning trials using a novel induced spawning technique, ovarian lavage. Chorulon(®) (human chorionic gonadotropin, hCG) was injected into a catheter inserted into the oviduct at a rate of 3 μl/g body weight. In one trial, a female paired with a male spawned in an aquarium at about 72 h post-treatment. In other trials, females were hand-stripped of eggs at 36 h post-treatment. There were 3680 eggs/g of eggs and females produced up to 24% of their body weight in eggs. Hatch resulted from all trials on the 4th day post-fertilization. Ovarian lavage is a simple method for administering spawning hormones, uses a catheter technique similar to that frequently performed to determine egg maturity in broodstock, and eliminates the need for injection.
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Affiliation(s)
- Craig A Watson
- Tropical Aquaculture Laboratory, Program in Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, Institute of Food and Agricultural Sciences, University of Florida, Ruskin, Florida, USA
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12
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Barnes DW, Parton A, Tomana M, Hwang JH, Czechanski A, Fan L, Collodi P. Stem cells from cartilaginous and bony fish. Methods Cell Biol 2008; 86:343-67. [PMID: 18442656 DOI: 10.1016/s0091-679x(08)00016-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- David W Barnes
- Mount Desert Island Biological Laboratory, Salisbury Cove, Maine, USA
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Ocalewicz K. Cytogenetic analysis of platyfish (Xiphophorus maculatus) shows location of major and minor rDNA on chromosomes. Hereditas 2006; 141:333-7. [PMID: 15703052 DOI: 10.1111/j.1601-5223.2004.01846.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Chromosome distribution of nucleolus organizer regions (NORs) and 5S rDNA loci were investigated in platyfish (Xiphophorus maculates) using conventional and molecular cytogenetic techniques. Chromomycin A3 (CMA3) staining of GC- rich heterochromatin provided four CMA3 cytotypes in studied platyfish. As in fish, CMA3 positive sites are related to NORs, chromosomes sequentially stained by CMA3 and AgNO3 showed bright blocks that were transcriptionaly active NORs. Additionally, PRINS with primers enabling amplification of 5S rDNA and CMA3 staining revealed existence of 5S rDNA sites located close to GC rich regions. The analysis could suggests that minor and major rDNAs may be linked.
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Affiliation(s)
- Konrad Ocalewicz
- Department of Evolutionary Genetics, University of Warmia and Mazury in Olsztyn, Poland.
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Stemshorn KC, Nolte AW, Tautz D. A genetic map of Cottus gobio (Pisces, Teleostei) based on microsatellites can be linked to the physical map of Tetraodon nigroviridis. J Evol Biol 2005; 18:1619-24. [PMID: 16313473 DOI: 10.1111/j.1420-9101.2005.00929.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
To initiate QTL studies in the nonmodel fish Cottus gobio we constructed a genetic map based on 171 microsatellite markers. The mapping panel consisted of F1 intercrosses between two divergent Cottus lineages from the River Rhine System. Basic local alignment search tool (BLAST) searches with the flanking sequences of the microsatellite markers yielded a significant (e < 10(-5)) hit with the Tetraodon nigroviridis genomic sequence for 45% of the Cottus loci. Remarkably, most of these hits were due to short highly conserved noncoding stretches. These have an average length of 40 bp and are on average 92% conserved. Comparison of the map locations between the two genomes revealed extensive conserved synteny, suggesting that the Tetraodon genomic sequence will serve as an excellent genomic reference for at least the Acanthopterygii, which include evolutionarily interesting fish groups such as guppies (Poecilia), cichlids (Tilapia) or Xiphophorus (Platy). The apparent high density of short conserved noncoding stretches in these fish genomes will highly facilitate the identification of genes that have been identified in QTL mapping strategies of evolutionary relevant traits.
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Affiliation(s)
- K C Stemshorn
- Department of Genetics, University of Cologne, Cologne, Germany
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15
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Kai W, Kikuchi K, Fujita M, Suetake H, Fujiwara A, Yoshiura Y, Ototake M, Venkatesh B, Miyaki K, Suzuki Y. A genetic linkage map for the tiger pufferfish, Takifugu rubripes. Genetics 2005; 171:227-38. [PMID: 15972462 PMCID: PMC1456513 DOI: 10.1534/genetics.105.042051] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The compact genome of the tiger pufferfish, Takifugu rubripes (fugu), has been sequenced to the "draft" level and annotated to identify all the genes. However, the assembly of the draft genome sequence is highly fragmented due to the lack of a genetic or a physical map. To determine the long-range linkage relationship of the sequences, we have constructed the first genetic linkage map for fugu. The maps for the male and female spanning 697.1 and 1213.5 cM, respectively, were arranged into 22 linkage groups by markers heterozygous in both parents. The resulting map consists of 200 microsatellite loci physically linked to genome sequences spanning approximately 39 Mb in total. Comparisons of the genome maps of fugu, other teleosts, and mammals suggest that syntenic relationship is more conserved in the teleost lineage than in the mammalian lineage. Map comparisons also show a pufferfish lineage-specific rearrangement of the genome resulting in colocalization of two Hox gene clusters in one linkage group. This map provides a foundation for development of a complete physical map, a basis for comparison of long-range linkage of genes with other vertebrates, and a resource for mapping loci responsible for phenotypic differences among Takifugu species.
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Affiliation(s)
- Wataru Kai
- Fisheries Laboratory, The University of Tokyo, Maisaka, Shizuoka, Japan
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16
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Jaillon O, Aury JM, Brunet F, Petit JL, Stange-Thomann N, Mauceli E, Bouneau L, Fischer C, Ozouf-Costaz C, Bernot A, Nicaud S, Jaffe D, Fisher S, Lutfalla G, Dossat C, Segurens B, Dasilva C, Salanoubat M, Levy M, Boudet N, Castellano S, Anthouard V, Jubin C, Castelli V, Katinka M, Vacherie B, Biémont C, Skalli Z, Cattolico L, Poulain J, De Berardinis V, Cruaud C, Duprat S, Brottier P, Coutanceau JP, Gouzy J, Parra G, Lardier G, Chapple C, McKernan KJ, McEwan P, Bosak S, Kellis M, Volff JN, Guigó R, Zody MC, Mesirov J, Lindblad-Toh K, Birren B, Nusbaum C, Kahn D, Robinson-Rechavi M, Laudet V, Schachter V, Quétier F, Saurin W, Scarpelli C, Wincker P, Lander ES, Weissenbach J, Roest Crollius H. Genome duplication in the teleost fish Tetraodon nigroviridis reveals the early vertebrate proto-karyotype. Nature 2004; 431:946-57. [PMID: 15496914 DOI: 10.1038/nature03025] [Citation(s) in RCA: 1406] [Impact Index Per Article: 70.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2004] [Accepted: 09/08/2004] [Indexed: 12/16/2022]
Abstract
Tetraodon nigroviridis is a freshwater puffer fish with the smallest known vertebrate genome. Here, we report a draft genome sequence with long-range linkage and substantial anchoring to the 21 Tetraodon chromosomes. Genome analysis provides a greatly improved fish gene catalogue, including identifying key genes previously thought to be absent in fish. Comparison with other vertebrates and a urochordate indicates that fish proteins have diverged markedly faster than their mammalian homologues. Comparison with the human genome suggests approximately 900 previously unannotated human genes. Analysis of the Tetraodon and human genomes shows that whole-genome duplication occurred in the teleost fish lineage, subsequent to its divergence from mammals. The analysis also makes it possible to infer the basic structure of the ancestral bony vertebrate genome, which was composed of 12 chromosomes, and to reconstruct much of the evolutionary history of ancient and recent chromosome rearrangements leading to the modern human karyotype.
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Affiliation(s)
- Olivier Jaillon
- UMR 8030 Genoscope, CNRS and Université d'Evry, 2 rue Gaston Crémieux, 91057 Evry Cedex, France
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17
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Fischer C, Bouneau L, Coutanceau JP, Weissenbach J, Volff JN, Ozouf-Costaz C. Global heterochromatic colocalization of transposable elements with minisatellites in the compact genome of the pufferfish Tetraodon nigroviridis. Gene 2004; 336:175-83. [PMID: 15246529 DOI: 10.1016/j.gene.2004.04.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2004] [Revised: 03/31/2004] [Accepted: 04/13/2004] [Indexed: 11/24/2022]
Abstract
Because of its unusual high degree of compaction and paucity of repetitive sequences, the genome of the smooth pufferfish Tetraodon nigroviridis is the subject of a well-advanced sequencing project. An astonishing diversity of transposable elements not found in the human and the mouse has been observed in the genome of T. nigroviridis. Due to the difficulty of assembling repeat-rich regions, the whole genome shotgun sequencing approach will probably fail to reveal the general organisation of this compact vertebrate genome. Therefore, in order to gain new insights into the global distribution pattern of repeated DNA in the genome of T. nigroviridis, we have reconstructed partial/complete repetitive sequences from data generated by the genome project and performed double-colour fluorescent in situ hybridization (FISH) analysis for representatives of three major categories of repeated sequences including two minisatellites (ms100 and ms104), two DNA transposons (Tol2 and Buffy1) and two non-long terminal repeat (LTR) retrotransposons (Rex3 and Babar). We show that DNA transposons and retroelements very frequently colocalize with minisatellites and mostly accumulate within heterochromatic regions. These results, which have not been reported so far for the fugu Takifugu rubripes, show that repeated elements are generally excluded from gene-rich regions in T. nigroviridis and underline the extreme degree of compartmentalization of this compact genome. The genome organization of the pufferfish is clearly different from that observed in humans, where repeated sequences make up an important fraction of euchromatic DNA, and is more similar to that observed in the fruit fly Drosophila melanogaster.
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Affiliation(s)
- Cécile Fischer
- Genoscope/Centre National de Séquençage and CNRS-UMR 8030, F-91057, Evry Cedex 06, France
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18
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Grützner F, Roest Crollius H, Lütjens G, Jaillon O, Weissenbach J, Ropers HH, Haaf T. Four-hundred million years of conserved synteny of human Xp and Xq genes on three Tetraodon chromosomes. Genome Res 2002; 12:1316-22. [PMID: 12213768 PMCID: PMC186653 DOI: 10.1101/gr.222402] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The freshwater pufferfish Tetraodon nigroviridis (TNI) has become highly attractive as a compact reference vertebrate genome for gene finding and validation. We have mapped genes, which are more or less evenly spaced on the human chromosomes 9 and X, on Tetraodon chromosomes using fluorescence in situ hybridization (FISH), to establish syntenic relationships between Tetraodon and other key vertebrate genomes. PufferFISH revealed that the human X is an orthologous mosaic of three Tetraodon chromosomes. More than 350 million years ago, an ancestral vertebrate autosome shared orthologous Xp and Xq genes with Tetraodon chromosomes 1 and 7. The shuffled order of Xp and Xq orthologs on their syntenic Tetraodon chromosomes can be explained by the prevalence of evolutionary inversions. The Tetraodon 2 orthologous genes are clustered in human Xp11 and represent a recent addition to the eutherian X sex chromosome. The human chromosome 9 and the avian Z sex chromosome show a much lower degree of synteny conservation in the pufferfish than the human X chromosome. We propose that a special selection process during vertebrate evolution has shaped a highly conserved array(s) of X-linked genes long before the X was used as a mammalian sex chromosome and many X chromosomal genes were recruited for reproduction and/or the development of cognitive abilities. [Sequence data reported in this paper have been deposited in GenBank and assigned the following accession no: AJ308098.]
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Affiliation(s)
- Frank Grützner
- Comparative Genomics Group, Research School of Biological Sciences, Australian National University, Canberra, ACT 2601, Australia
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19
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Zend-Ajusch E, Hornung U, Burgtorf C, Lütjens G, Shan Z, Schartl M, Haaf T. Isolation and characterization of cold-shock domain protein genes, Oryzias latipes Y-box protein 2 (OlaYP2) and Fugu rubripes Y-box protein 1 (FruYP1), in medakafish and pufferfish. Gene 2002; 296:111-9. [PMID: 12383508 DOI: 10.1016/s0378-1119(02)00838-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The Y-box protein (YP) family shares a nucleic acid binding domain, called cold-shock domain, that has been evolutionarily highly conserved from bacteria to human. The different YPs identified so far in vertebrates are thought to function as transcriptional activators, transcriptional repressors and/or translational repressors. Medakafish and pufferfish are very suitable vertebrate models for the study of developmental genetics and comparative genomics, respectively. Here we report the isolation of two teleost YP genes, medakafish Oryzias latipes (Ola)YP2 and Fugu rubripes (Fru)YP1, which are expressed in multiple tissues. Phylogenetic analysis demonstrated that OlaYP2 and FruYP1 belong to different subclasses of the cold-shock domain protein genes. Future studies in suitable model systems, like the medaka for developmental biology and Fugu for evolutionary genomics, are expected to contribute to our understanding of YPs.
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Affiliation(s)
- Enchshargal Zend-Ajusch
- Research School of Biological Sciences, Australian National University, Canberra, ACT 2601, Australia
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Roest Crollius H, Jaillon O, Bernot A, Pelletier E, Dasilva C, Bouneau L, Burge C, Yeh RF, Quetier F, Saurin W, Weissenbach J. Genome-wide comparisons between human and tetraodon. ERNST SCHERING RESEARCH FOUNDATION WORKSHOP 2002:11-29. [PMID: 11859562 DOI: 10.1007/978-3-662-04667-8_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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21
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Mandrioli M, Manicardi GC. Cytogenetic and molecular analysis of the pufferfish Tetraodon fluviatilis (Osteichthyes). Genetica 2002; 111:433-8. [PMID: 11841187 DOI: 10.1023/a:1013787230829] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In view of their compact genome, pufferfish (Tetraodontiformes) have been proposed as model animal for the study of the vertebrate genome. Despite such interest, cytogenetic information about puffers is still scanty. To fill this gap, a cytogenetic analysis of T. fluviatilis has been performed using both classical and molecular techniques. C-banding, followed by DAPI staining, evidenced that in T. fluviatilis, like all other puffer species so far examined, heterochromatin is essentially AT-rich and it is located at centromeres, whereas staining with CMA3, silver staining and FISH with a 28S ribosomal RNA gene DNA probe showed 2-4 nucleolar organizing regions (NORs) located in heterochromatic regions in the considered puffer species. FISH with the 5S probe put in evidence both in T. fluviatilis and in T. nigroviridis only a 5S cluster per haploid genome that is physically unlinked with the major ribosomal RNA genes including the 28S rRNA genes. Hybridization with the (TTAGGG)n probe showed in all the puffers brightly fluorescent signals uniform both in size and intensity at the end of all the chromosomes. Finally, mariner-like elements (MLEs) have been identified in T. fluviatilis and they have located into the NOR-associated heterochromatin.
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Affiliation(s)
- M Mandrioli
- Dipartimento di Biologia Animale, Università degli Studi di Modena e Reggio Emilia, Modena, Italy.
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22
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Brunner B, Grützner F, Yaspo ML, Ropers HH, Haaf T, Kalscheuer VM. Molecular cloning and characterization of the Fugu rubripes MEST/COPG2 imprinting cluster and chromosomal localization in Fugu and Tetraodon nigroviridis. Chromosome Res 2001; 8:465-76. [PMID: 11032317 DOI: 10.1023/a:1009263504671] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We isolated Fugu genomic clones using the human MEST (Mesoderm-Specific Transcript) cDNA as probe. Sequence analysis revealed the presence of MEST and three additional genes which show homology to plant DNBP (DNA-Binding Protein), vertebrate COPG2 (Coat Protein Gamma 2), as well as to human and mouse UCN (Urocortin). Structures of Fugu and human MEST, COPG2 and UCN genes are very similar. Since MEST and COPG2 are neighboring genes on human chromosome 7q32, we can conclude that we identified their orthologs and that linkage of these genes is evolutionarily conserved in vertebrates. Unlike human MEST which underlies isoform-specific imprinting and is methylated in a parent-of-origin-specific fashion, the CpG island of the Fugu ortholog is completely methylated. The translation start of Fugu MEST is identical to the non-imprinted human isoform which is in good agreement with the assumption that genomic imprinting is restricted to mammals. Comparative mapping of these genes by fluorescence in-situ hybridization to metaphase chromosomes of Fugu rubripes and Tetraodon nigroviridis showed clear signals on one of the smallest acrocentric chromosomal pairs, which in Fugu, can be easily classified by its unique triangular shape.
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Affiliation(s)
- B Brunner
- Human Genetics, University Hospital Nijmegen, The Netherlands
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23
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Yue GH, Li Y, Hill JA, Orban L. Microsatellites from the compact genome of the green spotted pufferfish (Tetraodon nigroviridis). Mol Ecol 2000; 9:2205-6. [PMID: 11123655 DOI: 10.1046/j.1365-294x.2000.105327.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- G H Yue
- Laboratory of Fish Biotechnology, Institute of Molecular Agrobiology, 1 Research Link, NUS Campus, National University of Singapore, 117604 Singapore
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24
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Roest Crollius H, Jaillon O, Dasilva C, Ozouf-Costaz C, Fizames C, Fischer C, Bouneau L, Billault A, Quetier F, Saurin W, Bernot A, Weissenbach J. Characterization and repeat analysis of the compact genome of the freshwater pufferfish Tetraodon nigroviridis. Genome Res 2000; 10:939-49. [PMID: 10899143 PMCID: PMC310905 DOI: 10.1101/gr.10.7.939] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Tetraodon nigroviridis is a freshwater pufferfish 20-30 million years distant from Fugu rubripes. The genome of both tetraodontiforms is compact, mostly because intergenic and intronic sequences are reduced in size compared to other vertebrate genomes. The previously uncharacterized Tetraodon genome is described here together with a detailed analysis of its repeat content and organization. We report the sequencing of 46 megabases of bacterial artificial chromosome (BAC) end sequences, which represents a random DNA sample equivalent to 13% of the genome. The sequence and location of rRNA gene clusters, centromeric and subtelocentric satellite sequences have been determined. Minisatellites and microsatellites have been cataloged and notable differences were observed in comparison with microsatellites from Fugu. The genome contains homologies to all known families of transposable elements, including Ty3-gypsy, Ty1-copia, Line retrotransposons, DNA transposons, and retroviruses, although their overall abundance is <1%. This structural analysis is an important prerequisite to sequencing the Tetraodon genome.
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