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Brannan EO, Hartley GA, O’Neill RJ. Mechanisms of Rapid Karyotype Evolution in Mammals. Genes (Basel) 2023; 15:62. [PMID: 38254952 PMCID: PMC10815390 DOI: 10.3390/genes15010062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 12/27/2023] [Accepted: 12/28/2023] [Indexed: 01/24/2024] Open
Abstract
Chromosome reshuffling events are often a foundational mechanism by which speciation can occur, giving rise to highly derivative karyotypes even amongst closely related species. Yet, the features that distinguish lineages prone to such rapid chromosome evolution from those that maintain stable karyotypes across evolutionary time are still to be defined. In this review, we summarize lineages prone to rapid karyotypic evolution in the context of Simpson's rates of evolution-tachytelic, horotelic, and bradytelic-and outline the mechanisms proposed to contribute to chromosome rearrangements, their fixation, and their potential impact on speciation events. Furthermore, we discuss relevant genomic features that underpin chromosome variation, including patterns of fusions/fissions, centromere positioning, and epigenetic marks such as DNA methylation. Finally, in the era of telomere-to-telomere genomics, we discuss the value of gapless genome resources to the future of research focused on the plasticity of highly rearranged karyotypes.
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Affiliation(s)
- Emry O. Brannan
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA; (E.O.B.); (G.A.H.)
| | - Gabrielle A. Hartley
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA; (E.O.B.); (G.A.H.)
| | - Rachel J. O’Neill
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA; (E.O.B.); (G.A.H.)
- Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269, USA
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2
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Dumas F, Perelman PL, Biltueva L, Roelke-Parker ME. Retrotransposon mapping in spider monkey genomes of the family Atelidae (Platyrrhini, Primates) shows a high level of LINE-1 amplification. JOURNAL OF BIOLOGICAL RESEARCH - BOLLETTINO DELLA SOCIETÀ ITALIANA DI BIOLOGIA SPERIMENTALE 2022. [DOI: 10.4081/jbr.2022.10725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
To investigate the distribution of LINE-1 repeat sequences, a LINE-1 probe was Fluorescence In Situ Hybridized (FISH) on the chromosomes of Ateles geoffroyi and Ateles fusciceps (Atelidae); a LINE-1 probe was also mapped on Cebuella pygmaea (Cebidae) and used as an outgroup for phylogenetic comparison. Ateles spider monkeys have a highly rearranged genome and are an ideal model for testing whether LINE-1 is involved in genome evolution. The LINE-1 probe has been mapped in the two Atelidae species for the first time, revealing a high accumulation of LINE-1 sequences along chromosomal arms, including telomeres, and a scarcity of LINE-1 signals at centromere positions. LINE-1 mapping in C. pygmaea (Cebidae) revealed signals at centromere positions and along chromosome arms, which was consistent with previous published data from other Cebidae species. In a broader sense, the results were analyzed in light of published data on whole-chromosomal human probes mapped in these genomes. This analysis allows us to speculate about the presence of LINE-1 sequences at the junction of human chromosomal syntenies, as well as a possible link between these sequences and chromosomal rearrangements.
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Migration of repetitive DNAs during evolution of the permanent translocation heterozygosity in the oyster plant (Tradescantia section Rhoeo). Chromosoma 2022; 131:163-173. [PMID: 35896680 PMCID: PMC9470650 DOI: 10.1007/s00412-022-00776-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 06/28/2022] [Accepted: 07/14/2022] [Indexed: 11/30/2022]
Abstract
Due to translocation heterozygosity for all chromosomes in the cell complement, the oyster plant (Tradescantia spathacea) forms a complete meiotic ring. It also shows Rabl-arrangement at interphase, featured by polar centromere clustering. We demonstrate that the pericentromeric regions of the oyster plant are homogenized in concert by three subtelomeric sequences: 45S rDNA, (TTTAGGG)n motif, and TSrepI repeat. The Rabl-based clustering of pericentromeric regions may have been an excellent device to combine the subtelomere-pericentromere sequence migration (via inversions) with the pericentromere-pericentromere DNA movement (via whole arm translocations) that altogether led to the concerted homogenization of all the pericentromeric domains by the subtelomeric sequences. We also show that the repetitive sequence landscape of interstitial chromosome regions contains many loci consisting of Arabidopsis-type telomeric sequence or of TSrepI repeat, and it is extensively heterozygous. However, the sequence arrangement on some chromosomal arms suggest segmental inversions that are fully or partially homozygous, a fact that could be explained if the inversions started to create linkages already in a bivalent-forming ancestor. Remarkably, the subterminal TSrepI loci reside exclusively on the longer arms that could be due to sharing sequences between similarly-sized chromosomal arms in the interphase nucleus. Altogether, our study spotlights the supergene system of the oyster plant as an excellent model to link complex chromosome rearrangements, evolution of repetitive sequences, and nuclear architecture.
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Ceraulo S, Perelman PL, Dumas F. Massive LINE‐1 retrotransposon enrichment in tamarins of the Cebidae family (Platyrrhini, Primates) and its significance for genome evolution. J ZOOL SYST EVOL RES 2021. [DOI: 10.1111/jzs.12536] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Simona Ceraulo
- Department of “Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF)” University of Palermo Palermo Italy
| | | | - Francesca Dumas
- Department of “Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF)” University of Palermo Palermo Italy
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5
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Chromosomal evolution in Raphicerus antelope suggests divergent X chromosomes may drive speciation through females, rather than males, contrary to Haldane's rule. Sci Rep 2021; 11:3152. [PMID: 33542477 PMCID: PMC7862234 DOI: 10.1038/s41598-021-82859-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 01/19/2021] [Indexed: 01/17/2023] Open
Abstract
Chromosome structural change has long been considered important in the evolution of post-zygotic reproductive isolation. The premise that karyotypic variation can serve as a possible barrier to gene flow is founded on the expectation that heterozygotes for structurally distinct chromosomal forms would be partially sterile (negatively heterotic) or show reduced recombination. We report the outcome of a detailed comparative molecular cytogenetic study of three antelope species, genus Raphicerus, that have undergone a rapid radiation. The species are largely conserved with respect to their euchromatic regions but the X chromosomes, in marked contrast, show distinct patterns of heterochromatic amplification and localization of repeats that have occurred independently in each lineage. We argue a novel hypothesis that postulates that the expansion of heterochromatic blocks in the homogametic sex can, with certain conditions, contribute to post-zygotic isolation. i.e., female hybrid incompatibility, the converse of Haldane’s rule. This is based on the expectation that hybrids incur a selective disadvantage due to impaired meiosis resulting from the meiotic checkpoint network’s surveillance of the asymmetric expansions of heterochromatic blocks in the homogametic sex. Asynapsis of these heterochromatic regions would result in meiotic silencing of unsynapsed chromatin and, if this persists, germline apoptosis and female infertility.
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6
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Centromere scission drives chromosome shuffling and reproductive isolation. Proc Natl Acad Sci U S A 2020; 117:7917-7928. [PMID: 32193338 DOI: 10.1073/pnas.1918659117] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
A fundamental characteristic of eukaryotic organisms is the generation of genetic variation via sexual reproduction. Conversely, significant large-scale genome structure variations could hamper sexual reproduction, causing reproductive isolation and promoting speciation. The underlying processes behind large-scale genome rearrangements are not well understood and include chromosome translocations involving centromeres. Recent genomic studies in the Cryptococcus species complex revealed that chromosome translocations generated via centromere recombination have reshaped the genomes of different species. In this study, multiple DNA double-strand breaks (DSBs) were generated via the CRISPR/Cas9 system at centromere-specific retrotransposons in the human fungal pathogen Cryptococcus neoformans The resulting DSBs were repaired in a complex manner, leading to the formation of multiple interchromosomal rearrangements and new telomeres, similar to chromothripsis-like events. The newly generated strains harboring chromosome translocations exhibited normal vegetative growth but failed to undergo successful sexual reproduction with the parental wild-type strain. One of these strains failed to produce any spores, while another produced ∼3% viable progeny. The germinated progeny exhibited aneuploidy for multiple chromosomes and showed improved fertility with both parents. All chromosome translocation events were accompanied without any detectable change in gene sequences and thus suggest that chromosomal translocations alone may play an underappreciated role in the onset of reproductive isolation and speciation.
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7
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Abstract
Marsupial genomes, which are packaged into large chromosomes, provide a powerful resource for studying the mechanisms of genome evolution. The extensive and valuable body of work on marsupial cytogenetics, combined more recently with genome sequence data, has enabled prediction of the 2n = 14 karyotype ancestral to all marsupial families. The application of both chromosome biology and genome sequencing, or chromosomics, has been a necessary approach for various aspects of mammalian genome evolution, such as understanding sex chromosome evolution and the origin and evolution of transmissible tumors in Tasmanian devils. The next phase of marsupial genome evolution research will employ chromosomics approaches to begin addressing fundamental questions in marsupial genome evolution and chromosome evolution more generally. The answers to these complex questions will impact our understanding across a broad range of fields, including the genetics of speciation, genome adaptation to environmental stressors, and species management.
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Affiliation(s)
- Janine E Deakin
- Institute for Applied Ecology, University of Canberra, Canberra, Australian Capital Territory 2617, Australia;
| | - Rachel J O'Neill
- Department of Molecular and Cell Biology and Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269, USA;
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Ling YH, Lin Z, Yuen KWY. Genetic and epigenetic effects on centromere establishment. Chromosoma 2019; 129:1-24. [PMID: 31781852 DOI: 10.1007/s00412-019-00727-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/24/2019] [Accepted: 10/10/2019] [Indexed: 01/19/2023]
Abstract
Endogenous chromosomes contain centromeres to direct equal chromosomal segregation in mitosis and meiosis. The location and function of existing centromeres is usually maintained through cell cycles and generations. Recent studies have investigated how the centromere-specific histone H3 variant CENP-A is assembled and replenished after DNA replication to epigenetically propagate the centromere identity. However, existing centromeres occasionally become inactivated, with or without change in underlying DNA sequences, or lost after chromosomal rearrangements, resulting in acentric chromosomes. New centromeres, known as neocentromeres, may form on ectopic, non-centromeric chromosomal regions to rescue acentric chromosomes from being lost, or form dicentric chromosomes if the original centromere is still active. In addition, de novo centromeres can form after chromatinization of purified DNA that is exogenously introduced into cells. Here, we review the phenomena of naturally occurring and experimentally induced new centromeres and summarize the genetic (DNA sequence) and epigenetic features of these new centromeres. We compare the characteristics of new and native centromeres to understand whether there are different requirements for centromere establishment and propagation. Based on our understanding of the mechanisms of new centromere formation, we discuss the perspectives of developing more stably segregating human artificial chromosomes to facilitate gene delivery in therapeutics and research.
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Affiliation(s)
- Yick Hin Ling
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong
| | - Zhongyang Lin
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong
| | - Karen Wing Yee Yuen
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong.
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9
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Smalec BM, Heider TN, Flynn BL, O'Neill RJ. A centromere satellite concomitant with extensive karyotypic diversity across the Peromyscus genus defies predictions of molecular drive. Chromosome Res 2019; 27:237-252. [PMID: 30771198 PMCID: PMC6733818 DOI: 10.1007/s10577-019-09605-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/26/2019] [Accepted: 01/29/2019] [Indexed: 12/17/2022]
Abstract
A common feature of eukaryotic centromeres is the presence of large tracts of tandemly arranged repeats, known as satellite DNA. However, these centromeric repeats appear to experience rapid evolution under forces such as molecular drive and centromere drive, seemingly without consequence to the integrity of the centromere. Moreover, blocks of heterochromatin within the karyotype, including the centromere, are hotspots for chromosome rearrangements that may drive speciation events by contributing to reproductive isolation. However, the relationship between the evolution of heterochromatic sequences and the karyotypic dynamics of these regions remains largely unknown. Here, we show that a single conserved satellite DNA sequence in the order Rodentia of the genus Peromyscus localizes to recurrent sites of chromosome rearrangements and heterochromatic amplifications. Peromyscine species display several unique features of chromosome evolution compared to other Rodentia, including stable maintenance of a strict chromosome number of 48 among all known species in the absence of any detectable interchromosomal rearrangements. Rather, the diverse karyotypes of Peromyscine species are due to intrachromosomal variation in blocks of repeated DNA content. Despite wide variation in the copy number and location of repeat blocks among different species, we find that a single satellite monomer maintains a conserved sequence and homogenized tandem repeat structure, defying predictions of molecular drive. The conservation of this satellite monomer results in common, abundant, and large blocks of chromatin that are homologous among chromosomes within one species and among diverged species. Thus, such a conserved repeat may have facilitated the retention of polymorphic chromosome variants within individuals and intrachromosomal rearrangements between species-both factors that have previously been hypothesized to contribute towards the extremely wide range of ecological adaptations that this genus exhibits.
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Affiliation(s)
- Brendan M Smalec
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, 67 North Eagleville Road, Unit 3127, Storrs, CT, 06269, USA
| | - Thomas N Heider
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, 67 North Eagleville Road, Unit 3127, Storrs, CT, 06269, USA
| | - Brianna L Flynn
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, 67 North Eagleville Road, Unit 3127, Storrs, CT, 06269, USA
| | - Rachel J O'Neill
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, 67 North Eagleville Road, Unit 3127, Storrs, CT, 06269, USA.
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10
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Celik M, Cascini M, Haouchar D, Van Der Burg C, Dodt W, Evans AR, Prentis P, Bunce M, Fruciano C, Phillips MJ. A molecular and morphometric assessment of the systematics of the Macropus complex clarifies the tempo and mode of kangaroo evolution. Zool J Linn Soc 2019. [DOI: 10.1093/zoolinnean/zlz005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Mélina Celik
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Manuela Cascini
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Dalal Haouchar
- Trace and Environmental DNA (TrEnD) Laboratory, Curtin University, Perth, WA, Australia
| | - Chloe Van Der Burg
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - William Dodt
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Alistair R Evans
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Peter Prentis
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Michael Bunce
- Trace and Environmental DNA (TrEnD) Laboratory, Curtin University, Perth, WA, Australia
| | - Carmelo Fruciano
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
- Institut de biologie de l’Ecole normale supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, PSL Université Paris, Paris, France
| | - Matthew J Phillips
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
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11
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Centromere Repeats: Hidden Gems of the Genome. Genes (Basel) 2019; 10:genes10030223. [PMID: 30884847 PMCID: PMC6471113 DOI: 10.3390/genes10030223] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/07/2019] [Accepted: 03/11/2019] [Indexed: 01/08/2023] Open
Abstract
Satellite DNAs are now regarded as powerful and active contributors to genomic and chromosomal evolution. Paired with mobile transposable elements, these repetitive sequences provide a dynamic mechanism through which novel karyotypic modifications and chromosomal rearrangements may occur. In this review, we discuss the regulatory activity of satellite DNA and their neighboring transposable elements in a chromosomal context with a particular emphasis on the integral role of both in centromere function. In addition, we discuss the varied mechanisms by which centromeric repeats have endured evolutionary processes, producing a novel, species-specific centromeric landscape despite sharing a ubiquitously conserved function. Finally, we highlight the role these repetitive elements play in the establishment and functionality of de novo centromeres and chromosomal breakpoints that underpin karyotypic variation. By emphasizing these unique activities of satellite DNAs and transposable elements, we hope to disparage the conventional exemplification of repetitive DNA in the historically-associated context of ‘junk’.
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12
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The methylation and telomere landscape in two families of marsupials with different rates of chromosome evolution. Chromosome Res 2018; 26:317-332. [PMID: 30539406 DOI: 10.1007/s10577-018-9593-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/22/2018] [Accepted: 11/23/2018] [Indexed: 02/07/2023]
Abstract
Two marsupial families exemplify divergent rates of karyotypic change. The Dasyurid family has an extremely conserved karyotype. In contrast, there is significant chromosomal variation within the Macropodidae family, best exemplified by members of the genus Petrogale (rock-wallabies). Both families are also distinguished by their telomere landscape (length and epigenetics), with the dasyurids having a unique telomere length dimorphism not observed in other marsupials and hypothesised to be regulated in a parent-of-origin fashion. Previous work has shown that proximal ends of chromosomes are enriched in cytosine methylation in dasyurids, but that the chromosomes of a macropod, the tammar wallaby, have DNA methylation enrichment of pericentric regions. Using a combination of telomere and 5-methylcytosine immunofluorescence staining, we investigated the telomere landscape of four dasyurid and three Petrogale species. As part of this study, we also further examined the parent-of-origin hypothesis for the regulation of telomere length dimorphism in dasyurids, using epigenetic modifications known to differentiate the active maternal X chromosome, including 5-methylcytosine methylation and histone modifications H3K4me2, H3K9ac and H4Kac. Our results give further support to the parent-of-origin hypothesis for the regulation of telomere length dimorphism in dasyurids, where the paternally derived X chromosome in females was associated with long telomeres and the maternally derived with short telomeres. In contrast to the tammar wallaby, rock-wallabies demonstrated a similar 5-methylcytosine staining pattern across all chromosomes to that of dasyurids, suggesting that DNA methylation of telomeric regions is not responsible for differences in the rates of chromosome evolution between these two families.
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13
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Eldridge MDB, Potter S, Helgen KM, Sinaga MH, Aplin KP, Flannery TF, Johnson RN. Phylogenetic analysis of the tree-kangaroos (Dendrolagus) reveals multiple divergent lineages within New Guinea. Mol Phylogenet Evol 2018; 127:589-599. [PMID: 29807156 DOI: 10.1016/j.ympev.2018.05.030] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 05/22/2018] [Accepted: 05/24/2018] [Indexed: 11/25/2022]
Abstract
Amongst the Australasian kangaroos and wallabies (Macropodidae) one anomalous genus, the tree-kangaroos, Dendrolagus, has secondarily returned to arboreality. Modern tree-kangaroos are confined to the wet tropical forests of north Queensland, Australia (2 species) and New Guinea (8 species). Due to their behavior, distribution and habitat most species are poorly known and our understanding of the evolutionary history and systematics of the genus is limited and controversial. We obtained tissue samples from 36 individual Dendrolagus including representatives from 14 of the 17 currently recognised or proposed subspecies and generated DNA sequence data from three mitochondrial (3116 bp) and five nuclear (4097 bp) loci. Phylogenetic analysis of these multi-locus data resolved long-standing questions regarding inter-relationships within Dendrolagus. The presence of a paraphyletic ancestral long-footed and derived monophyletic short-footed group was confirmed. Six major lineages were identified: one in Australia (D. lumholtzi, D. bennettianus) and five in New Guinea (D. inustus, D. ursinus, a Goodfellow's group, D. mbaiso and a Doria's group). Two major episodes of diversification within Dendrolagus were identified: the first during the late Miocene/early Pliocene associated with orogenic processes in New Guinea and the second mostly during the early Pleistocene associated with the intensification of climatic cycling. All sampled subspecies showed high levels of genetic divergence and currently recognized species within both the Doria's and Goodfellow's groups were paraphyletic indicating that adjustments to current taxonomy are warranted.
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Affiliation(s)
- Mark D B Eldridge
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, New South Wales 2010, Australia.
| | - Sally Potter
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, New South Wales 2010, Australia; Research School of Biology, Australian National University, Acton, ACT 0200, Australia; School of Life and Environmental Sciences, The University of Sydney, Sydney, Australia
| | - Kristofer M Helgen
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, New South Wales 2010, Australia; School of Biological Sciences, Environment Institute, Centre for Applied Conservation Science, and ARC Centre of Excellence for Australian Biodiversity and Heritage, University of Adelaide, Adelaide, SA 5005, Australia
| | - Martua H Sinaga
- Indonesian Institute of Sciences (LIPI) & Museum Bogoriense, Cibinong, West Java, Indonesia
| | - Ken P Aplin
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, New South Wales 2010, Australia; Wildlife Conservation Society, Goroka, Papua New Guinea
| | - Tim F Flannery
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, New South Wales 2010, Australia; Melbourne Sustainable Society Institute, Melbourne University, Parkville, Vic. 3010, Australia
| | - Rebecca N Johnson
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, New South Wales 2010, Australia
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14
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O'Neill MJ, O'Neill RJ. Sex chromosome repeats tip the balance towards speciation. Mol Ecol 2018; 27:3783-3798. [PMID: 29624756 DOI: 10.1111/mec.14577] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 03/08/2018] [Accepted: 03/26/2018] [Indexed: 12/11/2022]
Abstract
Because sex chromosomes, by definition, carry genes that determine sex, mutations that alter their structural and functional stability can have immediate consequences for the individual by reducing fertility, but also for a species by altering the sex ratio. Moreover, the sex-specific segregation patterns of heteromorphic sex chromosomes make them havens for selfish genetic elements that not only create suboptimal sex ratios but can also foster sexual antagonism. Compensatory mutations to mitigate antagonism or return sex ratios to a Fisherian optimum can create hybrid incompatibility and establish reproductive barriers leading to species divergence. The destabilizing influence of these selfish elements is often manifest within populations as copy number variants (CNVs) in satellite repeats and transposable elements (TE) or as CNVs involving sex-determining genes, or genes essential to fertility and sex chromosome dosage compensation. This review catalogs several examples of well-studied sex chromosome CNVs in Drosophilids and mammals that underlie instances of meiotic drive, hybrid incompatibility and disruptions to sex differentiation and sex chromosome dosage compensation. While it is difficult to pinpoint a direct cause/effect relationship between these sex chromosome CNVs and speciation, it is easy to see how their effects in creating imbalances between the sexes, and the compensatory mutations to restore balance, can lead to lineage splitting and species formation.
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Affiliation(s)
- Michael J O'Neill
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut
| | - Rachel J O'Neill
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut
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15
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Deakin JE. Chromosome Evolution in Marsupials. Genes (Basel) 2018; 9:E72. [PMID: 29415454 PMCID: PMC5852568 DOI: 10.3390/genes9020072] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 01/30/2018] [Accepted: 02/01/2018] [Indexed: 12/17/2022] Open
Abstract
Marsupials typically possess very large, distinctive chromosomes that make them excellent subjects for cytogenetic analysis, and the high level of conservation makes it relatively easy to track chromosome evolution. There are two speciose marsupial families with contrasting rates of karyotypic evolution that could provide insight into the mechanisms driving genome reshuffling and speciation. The family Dasyuridae displays exceptional karyotype conservation with all karyotyped species possessing a 2n = 14 karyotype similar to that predicted for the ancestral marsupial. In contrast, the family Macropodidae has experienced a higher rate of genomic rearrangement and one genus of macropods, the rock-wallabies (Petrogale), has experienced extensive reshuffling. For at least some recently diverged Petrogale species, there is still gene flow despite hybrid fertility issues, making this species group an exceptional model for studying speciation. This review highlights the unique chromosome features of marsupial chromosomes, particularly for these two contrasting families, and the value that a combined cytogenetics, genomics, and epigenomics approach will have for testing models of genome evolution and speciation.
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Affiliation(s)
- Janine E Deakin
- Institute for Applied Ecology, University of Canberra, Canberra, ACT 2617, Australia.
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16
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Klein SJ, O'Neill RJ. Transposable elements: genome innovation, chromosome diversity, and centromere conflict. Chromosome Res 2018; 26:5-23. [PMID: 29332159 PMCID: PMC5857280 DOI: 10.1007/s10577-017-9569-5] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 12/05/2017] [Accepted: 12/12/2017] [Indexed: 12/21/2022]
Abstract
Although it was nearly 70 years ago when transposable elements (TEs) were first discovered “jumping” from one genomic location to another, TEs are now recognized as contributors to genomic innovations as well as genome instability across a wide variety of species. In this review, we illustrate the ways in which active TEs, specifically retroelements, can create novel chromosome rearrangements and impact gene expression, leading to disease in some cases and species-specific diversity in others. We explore the ways in which eukaryotic genomes have evolved defense mechanisms to temper TE activity and the ways in which TEs continue to influence genome structure despite being rendered transpositionally inactive. Finally, we focus on the role of TEs in the establishment, maintenance, and stabilization of critical, yet rapidly evolving, chromosome features: eukaryotic centromeres. Across centromeres, specific types of TEs participate in genomic conflict, a balancing act wherein they are actively inserting into centromeric domains yet are harnessed for the recruitment of centromeric histones and potentially new centromere formation.
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Affiliation(s)
- Savannah J Klein
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, 06269, USA
| | - Rachel J O'Neill
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, 06269, USA.
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17
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de Sotero-Caio CG, Cabral-de-Mello DC, Calixto MDS, Valente GT, Martins C, Loreto V, de Souza MJ, Santos N. Centromeric enrichment of LINE-1 retrotransposons and its significance for the chromosome evolution of Phyllostomid bats. Chromosome Res 2017; 25:313-325. [PMID: 28916913 DOI: 10.1007/s10577-017-9565-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Revised: 08/24/2017] [Accepted: 08/28/2017] [Indexed: 10/18/2022]
Abstract
Despite their ubiquitous incidence, little is known about the chromosomal distribution of long interspersed elements (LINEs) in mammalian genomes. Phyllostomid bats, characterized by lineages with distinct trends of chromosomal evolution coupled with remarkable ecological and taxonomic diversity, represent good models to understand how these repetitive sequences contribute to the evolution of genome architecture and its link to lineage diversification. To test the hypothesis that LINE-1 sequences were important modifiers of bat genome architecture, we characterized the distribution of LINE-1-derived sequences on genomes of 13 phyllostomid species within a phylogenetic framework. We found massive accumulation of LINE-1 elements in the centromeres of most species: a rare phenomenon on mammalian genomes. We hypothesize that expansion of these elements has occurred early in the radiation of phyllostomids and recurred episodically. LINE-1 expansions on centromeric heterochromatin probably spurred chromosomal change before the radiation of phyllostomids into the extant 11 subfamilies and contributed to the high degree of karyotypic variation observed among different lineages. Understanding centromere architecture in a variety of taxa promises to explain how lineage-specific changes on centromere structure can contribute to karyotypic diversity while not disrupting functional constraints for proper cell division.
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Affiliation(s)
- Cibele Gomes de Sotero-Caio
- Departamento de Genética, Laboratório de Genética e Citogenética Animal e Humana, UFPE-Universidade Federal de Pernambuco, Av. da Engenharia s/n; Cidade Universitária, Recife, PE, CEP:50740-600, Brazil. .,Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA.
| | - Diogo Cavalcanti Cabral-de-Mello
- Departamento de Biologia, Grupo de Estudos em Citogenômica e Evolução Animal, UNESP-Universidade Estadual Paulista, Instituto de Biociências, Rio Claro, SP, Brazil
| | - Merilane da Silva Calixto
- Departamento de Genética, Laboratório de Genética e Citogenética Animal e Humana, UFPE-Universidade Federal de Pernambuco, Av. da Engenharia s/n; Cidade Universitária, Recife, PE, CEP:50740-600, Brazil.,Centro de Saúde e Tecnologia, Unidade Acadêmica de Ciências Biológicas, UFCG-Universidade Federal de Campina Grande, Patos, PB, Brazil
| | - Guilherme Targino Valente
- Departamento de Bioprocessos e Biotecnologia da Faculdade de Ciências Agronômicas, UNESP-Universidade Estadual Paulista, Botucatu, SP, Brazil
| | - Cesar Martins
- Departamento de Morfologia, Laboratório Genômica Integrativa, UNESP-Universidade Estadual Paulista, Botucatu, SP, Brazil
| | - Vilma Loreto
- Departamento de Genética, Laboratório de Genética e Citogenética Animal e Humana, UFPE-Universidade Federal de Pernambuco, Av. da Engenharia s/n; Cidade Universitária, Recife, PE, CEP:50740-600, Brazil
| | - Maria José de Souza
- Departamento de Genética, Laboratório de Genética e Citogenética Animal e Humana, UFPE-Universidade Federal de Pernambuco, Av. da Engenharia s/n; Cidade Universitária, Recife, PE, CEP:50740-600, Brazil
| | - Neide Santos
- Departamento de Genética, Laboratório de Genética e Citogenética Animal e Humana, UFPE-Universidade Federal de Pernambuco, Av. da Engenharia s/n; Cidade Universitária, Recife, PE, CEP:50740-600, Brazil
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18
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Dumetz F, Imamura H, Sanders M, Seblova V, Myskova J, Pescher P, Vanaerschot M, Meehan CJ, Cuypers B, De Muylder G, Späth GF, Bussotti G, Vermeesch JR, Berriman M, Cotton JA, Volf P, Dujardin JC, Domagalska MA. Modulation of Aneuploidy in Leishmania donovani during Adaptation to Different In Vitro and In Vivo Environments and Its Impact on Gene Expression. mBio 2017; 8:e00599-17. [PMID: 28536289 PMCID: PMC5442457 DOI: 10.1128/mbio.00599-17] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 05/01/2017] [Indexed: 12/23/2022] Open
Abstract
Aneuploidy is usually deleterious in multicellular organisms but appears to be tolerated and potentially beneficial in unicellular organisms, including pathogens. Leishmania, a major protozoan parasite, is emerging as a new model for aneuploidy, since in vitro-cultivated strains are highly aneuploid, with interstrain diversity and intrastrain mosaicism. The alternation of two life stages in different environments (extracellular promastigotes and intracellular amastigotes) offers a unique opportunity to study the impact of environment on aneuploidy and gene expression. We sequenced the whole genomes and transcriptomes of Leishmania donovani strains throughout their adaptation to in vivo conditions mimicking natural vertebrate and invertebrate host environments. The nucleotide sequences were almost unchanged within a strain, in contrast to highly variable aneuploidy. Although high in promastigotes in vitro, aneuploidy dropped significantly in hamster amastigotes, in a progressive and strain-specific manner, accompanied by the emergence of new polysomies. After a passage through a sand fly, smaller yet consistent karyotype changes were detected. Changes in chromosome copy numbers were correlated with the corresponding transcript levels, but additional aneuploidy-independent regulation of gene expression was observed. This affected stage-specific gene expression, downregulation of the entire chromosome 31, and upregulation of gene arrays on chromosomes 5 and 8. Aneuploidy changes in Leishmania are probably adaptive and exploited to modulate the dosage and expression of specific genes; they are well tolerated, but additional mechanisms may exist to regulate the transcript levels of other genes located on aneuploid chromosomes. Our model should allow studies of the impact of aneuploidy on molecular adaptations and cellular fitness.IMPORTANCE Aneuploidy is usually detrimental in multicellular organisms, but in several microorganisms, it can be tolerated and even beneficial. Leishmania-a protozoan parasite that kills more than 30,000 people each year-is emerging as a new model for aneuploidy studies, as unexpectedly high levels of aneuploidy are found in clinical isolates. Leishmania lacks classical regulation of transcription at initiation through promoters, so aneuploidy could represent a major adaptive strategy of this parasite to modulate gene dosage in response to stressful environments. For the first time, we document the dynamics of aneuploidy throughout the life cycle of the parasite, in vitro and in vivo We show its adaptive impact on transcription and its interaction with regulation. Besides offering a new model for aneuploidy studies, we show that further genomic studies should be done directly in clinical samples without parasite isolation and that adequate methods should be developed for this.
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Affiliation(s)
- F Dumetz
- Molecular Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
| | - H Imamura
- Molecular Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
| | - M Sanders
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - V Seblova
- Charles University, Prague, Czech Republic
| | - J Myskova
- Charles University, Prague, Czech Republic
| | - P Pescher
- Unité de Parasitologie Moléculaire et Signalisation, INSERM U1201, Institut Pasteur, Paris, France
| | - M Vanaerschot
- Molecular Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
| | - C J Meehan
- Mycobacteriology Unit, Institute of Tropical Medicine, Antwerp, Belgium
| | - B Cuypers
- Molecular Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
- Advanced Database Research and Modelling (ADReM), Department of Mathematics and Computer Science, University of Antwerp, Antwerp, Belgium
| | - G De Muylder
- Molecular Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
| | - G F Späth
- Unité de Parasitologie Moléculaire et Signalisation, INSERM U1201, Institut Pasteur, Paris, France
| | - G Bussotti
- Unité de Parasitologie Moléculaire et Signalisation, INSERM U1201, Institut Pasteur, Paris, France
| | - J R Vermeesch
- Molecular Cytogenetics and Genome Research, Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - M Berriman
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - J A Cotton
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - P Volf
- Charles University, Prague, Czech Republic
| | - J C Dujardin
- Molecular Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - M A Domagalska
- Molecular Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
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19
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Potter S, Bragg JG, Blom MPK, Deakin JE, Kirkpatrick M, Eldridge MDB, Moritz C. Chromosomal Speciation in the Genomics Era: Disentangling Phylogenetic Evolution of Rock-wallabies. Front Genet 2017; 8:10. [PMID: 28265284 PMCID: PMC5301020 DOI: 10.3389/fgene.2017.00010] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 01/18/2017] [Indexed: 12/24/2022] Open
Abstract
The association of chromosome rearrangements (CRs) with speciation is well established, and there is a long history of theory and evidence relating to "chromosomal speciation." Genomic sequencing has the potential to provide new insights into how reorganization of genome structure promotes divergence, and in model systems has demonstrated reduced gene flow in rearranged segments. However, there are limits to what we can understand from a small number of model systems, which each only tell us about one episode of chromosomal speciation. Progressing from patterns of association between chromosome (and genic) change, to understanding processes of speciation requires both comparative studies across diverse systems and integration of genome-scale sequence comparisons with other lines of evidence. Here, we showcase a promising example of chromosomal speciation in a non-model organism, the endemic Australian marsupial genus Petrogale. We present initial phylogenetic results from exon-capture that resolve a history of divergence associated with extensive and repeated CRs. Yet it remains challenging to disentangle gene tree heterogeneity caused by recent divergence and gene flow in this and other such recent radiations. We outline a way forward for better integration of comparative genomic sequence data with evidence from molecular cytogenetics, and analyses of shifts in the recombination landscape and potential disruption of meiotic segregation and epigenetic programming. In all likelihood, CRs impact multiple cellular processes and these effects need to be considered together, along with effects of genic divergence. Understanding the effects of CRs together with genic divergence will require development of more integrative theory and inference methods. Together, new data and analysis tools will combine to shed light on long standing questions of how chromosome and genic divergence promote speciation.
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Affiliation(s)
- Sally Potter
- Research School of Biology, Australian National University, ActonACT, Australia
- Australian Museum Research Institute, Australian Museum, SydneyNSW, Australia
| | - Jason G. Bragg
- National Herbarium of New South Wales, The Royal Botanic Gardens and Domain Trust, SydneyNSW, Australia
| | - Mozes P. K. Blom
- Department of Bioinformatics and Genetics, Swedish Museum of Natural HistoryStockholm, Sweden
| | - Janine E. Deakin
- Institute for Applied Ecology, University of Canberra, BruceACT, Australia
| | - Mark Kirkpatrick
- Department of Integrative Biology, University of Texas, AustinTX, USA
| | - Mark D. B. Eldridge
- Australian Museum Research Institute, Australian Museum, SydneyNSW, Australia
| | - Craig Moritz
- Research School of Biology, Australian National University, ActonACT, Australia
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20
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Wadley JJ, Fordham DA, Thomson VA, Ritchie EG, Austin JJ. Phylogeography of the antilopine wallaroo ( Macropus antilopinus) across tropical northern Australia. Ecol Evol 2016; 6:8050-8061. [PMID: 27878077 PMCID: PMC5108257 DOI: 10.1002/ece3.2381] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 07/13/2016] [Accepted: 07/18/2016] [Indexed: 12/03/2022] Open
Abstract
The distribution of antilopine wallaroo, Macropus antilopinus, is marked by a break in the species’ range between Queensland and the Northern Territory, coinciding with the Carpentarian barrier. Previous work on M. antilopinus revealed limited genetic differentiation between the Northern Territory and Queensland M. antilopinus populations across this barrier. The study also identified a number of divergent lineages in the Northern Territory, but was unable to elucidate any geographic structure. Here, we re‐examine these results to (1) determine phylogeographic patterns across the range of M. antilopinus and (2) infer the biogeographic barriers associated with these patterns. The tropical savannahs of northern Australia: from the Cape York Peninsula in the east, to the Kimberley in the west. We examined phylogeographic patterns in M. antilopinus using a larger number of samples and three mtDNA genes: NADH dehydrogenase subunit 2, cytochrome b, and the control region. Two datasets were generated and analyzed: (1) a subset of samples with all three mtDNA regions concatenated together and (2) all samples for just control region sequences that included samples from the previous study. Analysis included generating phylogenetic trees based on Bayesian analysis and intraspecific median‐joining networks. The contemporary spatial structure of M. antilopinus mtDNA lineages revealed five shallow clades and a sixth, divergent lineage. The genetic differences that we found between Queensland and Northern Territory M. antilopinus samples confirmed the split in the geographic distribution of the species. We also found weak genetic differentiation between Northern Territory samples and those from the Kimberley region of Western Australia, possibly due to the Kimberley Plateau–Arnhem Land barrier. Within the Northern Territory, two clades appear to be parapatric in the west, while another two clades are broadly sympatric across the Northern Territory. MtDNA diversity of M. antilopinus revealed an unexpectedly complex evolutionary history involving multiple sympatric and parapatric mtDNA clades across northern Australia. These phylogeographic patterns highlight the importance of investigating genetic variation across distributions of species and integrating this information into biodiversity conservation.
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Affiliation(s)
- Jessica J Wadley
- Australian Centre for Ancient DNAUniversity of AdelaideNorth TerraceAdelaideSouth Australia5005Australia; Environment Institute and School of Biological SciencesUniversity of AdelaideNorth TerraceAdelaideSouth Australia5005Australia
| | - Damien A Fordham
- Environment Institute and School of Biological Sciences University of Adelaide North Terrace Adelaide South Australia 5005 Australia
| | - Vicki A Thomson
- Australian Centre for Ancient DNAUniversity of AdelaideNorth TerraceAdelaideSouth Australia5005Australia; Environment Institute and School of Biological SciencesUniversity of AdelaideNorth TerraceAdelaideSouth Australia5005Australia
| | - Euan G Ritchie
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Burwood Victoria 3125 Australia
| | - Jeremy J Austin
- Australian Centre for Ancient DNAUniversity of AdelaideNorth TerraceAdelaideSouth Australia5005Australia; Environment Institute and School of Biological SciencesUniversity of AdelaideNorth TerraceAdelaideSouth Australia5005Australia; Sciences DepartmentMuseum VictoriaCarlton GardensMelbourneVictoria3001Australia
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21
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Huang YC, Lee CC, Kao CY, Chang NC, Lin CC, Shoemaker D, Wang J. Evolution of long centromeres in fire ants. BMC Evol Biol 2016; 16:189. [PMID: 27628313 PMCID: PMC5024525 DOI: 10.1186/s12862-016-0760-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 09/05/2016] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Centromeres are essential for accurate chromosome segregation, yet sequence conservation is low even among closely related species. Centromere drive predicts rapid turnover because some centromeric sequences may compete better than others during female meiosis. In addition to sequence composition, longer centromeres may have a transmission advantage. RESULTS We report the first observations of extremely long centromeres, covering on average 34 % of the chromosomes, in the red imported fire ant Solenopsis invicta. By comparison, cytological examination of Solenopsis geminata revealed typical small centromeric constrictions. Bioinformatics and molecular analyses identified CenSol, the major centromeric satellite DNA repeat. We found that CenSol sequences are very similar between the two species but the CenSol copy number in S. invicta is much greater than that in S. geminata. In addition, centromere expansion in S. invicta is not correlated with the duplication of CenH3. Comparative analyses revealed that several closely related fire ant species also possess long centromeres. CONCLUSIONS Our results are consistent with a model of simple runaway centromere expansion due to centromere drive. We suggest expanded centromeres may be more prevalent in hymenopteran insects, which use haplodiploid sex determination, than previously considered.
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Affiliation(s)
- Yu-Ching Huang
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Chih-Chi Lee
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Chia-Yi Kao
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Ni-Chen Chang
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
- Laboratory of Insect Social Evolution, The Rockefeller University, New York, NY USA
| | - Chung-Chi Lin
- Department of Biology, National Changhua University of Education, Changhua, Taiwan
| | - DeWayne Shoemaker
- United States Department of Agriculture, Agricultural Research Service, Gainesville, FL USA
- Entomology and Plant Pathology Department, University of Tennessee, Knoxville, TN USA
| | - John Wang
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
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Abstract
A considerable fraction of the eukaryotic genome is made up of satellite DNA constituted of tandemly repeated sequences. These elements are mainly located at centromeres, pericentromeres, and telomeres and are major components of constitutive heterochromatin. Although originally satellite DNA was thought silent and inert, an increasing number of studies are providing evidence on its transcriptional activity supporting, on the contrary, an unexpected dynamicity. This review summarizes the multiple structural roles of satellite noncoding RNAs at chromosome level. Indeed, satellite noncoding RNAs play a role in the establishment of a heterochromatic state at centromere and telomere. These highly condensed structures are indispensable to preserve chromosome integrity and genome stability, preventing recombination events, and ensuring the correct chromosome pairing and segregation. Moreover, these RNA molecules seem to be involved also in maintaining centromere identity and in elongation, capping, and replication of telomere. Finally, the abnormal variation of centromeric and pericentromeric DNA transcription across major eukaryotic lineages in stress condition and disease has evidenced the critical role that these transcripts may play and the potentially dire consequences for the organism.
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Evolutionary dynamics of two satellite DNA families in rock lizards of the genus Iberolacerta (Squamata, Lacertidae): different histories but common traits. Chromosome Res 2016; 23:441-61. [PMID: 26384818 DOI: 10.1007/s10577-015-9489-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Satellite DNAs compose a large portion of all higher eukaryotic genomes. The turnover of these highly repetitive sequences is an important element in genome organization and evolution. However, information about the structure and dynamics of reptilian satellite DNA is still scarce. Two satellite DNA families, HindIII and TaqI, have been previously characterized in four species of the genus Iberolacerta. These families showed different chromosomal locations, abundances, and evolutionary rates. Here, we extend the study of both satellite DNAs (satDNAs) to the remaining Iberolacerta species, with the aim to investigate the patterns of variability and factors influencing the evolution of these repetitive sequences. Our results revealed disparate patterns but also common traits in the evolutionary histories of these satellite families: (i) each satellite DNA is made up of a library of monomer variants or subfamilies shared by related species; (ii) species-specific profiles of satellite repeats are shaped by expansions and/or contractions of different variants from the library; (iii) different turnover rates, even among closely related species, result in great differences in overall sequence homogeneity and in concerted or non-concerted evolution patterns, which may not reflect the phylogenetic relationships among taxa. Contrasting turnover rates are possibly related to genomic constraints such as karyotype architecture and the interspersed organization of diverging repeat variants in satellite arrays. Moreover, rapid changes in copy number, especially in the centromeric HindIII satDNA, may have been associated with chromosomal rearrangements and even contributed to speciation within Iberolacerta.
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24
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Deakin JE, Kruger-Andrzejewska M. Marsupials as models for understanding the role of chromosome rearrangements in evolution and disease. Chromosoma 2016; 125:633-44. [PMID: 27255308 DOI: 10.1007/s00412-016-0603-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 05/19/2016] [Accepted: 05/23/2016] [Indexed: 12/28/2022]
Abstract
Chromosome rearrangements have been implicated in diseases, such as cancer, and speciation, but it remains unclear whether rearrangements are causal or merely a consequence of these processes. Two marsupial families with very different rates of karyotype evolution provide excellent models in which to study the role of chromosome rearrangements in a disease and evolutionary context. The speciose family Dasyuridae displays remarkable karyotypic conservation, with all species examined to date possessing nearly identical karyotypes. Despite the seemingly high degree of chromosome stability within this family, they appear prone to developing tumours, including transmissible devil facial tumours. In contrast, chromosome rearrangements have been frequent in the evolution of the species-rich family Macropodidae, which displays a high level of karyotypic diversity. In particular, the genus Petrogale (rock-wallabies) displays an extraordinary level of chromosome rearrangement among species. For six parapatric Petrogale species, it appears that speciation has essentially been caught in the act, providing an opportunity to determine whether chromosomal rearrangements are a cause or consequence of speciation in this system. This review highlights the reasons that these two marsupial families are excellent models for testing hypotheses for hotspots of chromosome rearrangement and deciphering the role of chromosome rearrangements in disease and speciation.
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Affiliation(s)
- Janine E Deakin
- Institute for Applied Ecology, University of Canberra, Canberra, ACT, 2617, Australia.
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25
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Chatterjee G, Sankaranarayanan SR, Guin K, Thattikota Y, Padmanabhan S, Siddharthan R, Sanyal K. Repeat-Associated Fission Yeast-Like Regional Centromeres in the Ascomycetous Budding Yeast Candida tropicalis. PLoS Genet 2016; 12:e1005839. [PMID: 26845548 PMCID: PMC4741521 DOI: 10.1371/journal.pgen.1005839] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 01/11/2016] [Indexed: 11/19/2022] Open
Abstract
The centromere, on which kinetochore proteins assemble, ensures precise chromosome segregation. Centromeres are largely specified by the histone H3 variant CENP-A (also known as Cse4 in yeasts). Structurally, centromere DNA sequences are highly diverse in nature. However, the evolutionary consequence of these structural diversities on de novo CENP-A chromatin formation remains elusive. Here, we report the identification of centromeres, as the binding sites of four evolutionarily conserved kinetochore proteins, in the human pathogenic budding yeast Candida tropicalis. Each of the seven centromeres comprises a 2 to 5 kb non-repetitive mid core flanked by 2 to 5 kb inverted repeats. The repeat-associated centromeres of C. tropicalis all share a high degree of sequence conservation with each other and are strikingly diverged from the unique and mostly non-repetitive centromeres of related Candida species--Candida albicans, Candida dubliniensis, and Candida lusitaniae. Using a plasmid-based assay, we further demonstrate that pericentric inverted repeats and the underlying DNA sequence provide a structural determinant in CENP-A recruitment in C. tropicalis, as opposed to epigenetically regulated CENP-A loading at centromeres in C. albicans. Thus, the centromere structure and its influence on de novo CENP-A recruitment has been significantly rewired in closely related Candida species. Strikingly, the centromere structural properties along with role of pericentric repeats in de novo CENP-A loading in C. tropicalis are more reminiscent to those of the distantly related fission yeast Schizosaccharomyces pombe. Taken together, we demonstrate, for the first time, fission yeast-like repeat-associated centromeres in an ascomycetous budding yeast.
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Affiliation(s)
- Gautam Chatterjee
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Sundar Ram Sankaranarayanan
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Krishnendu Guin
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Yogitha Thattikota
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Sreedevi Padmanabhan
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Rahul Siddharthan
- The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai, India
| | - Kaustuv Sanyal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
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26
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Du X, Servin B, Womack JE, Cao J, Yu M, Dong Y, Wang W, Zhao S. An update of the goat genome assembly using dense radiation hybrid maps allows detailed analysis of evolutionary rearrangements in Bovidae. BMC Genomics 2014; 15:625. [PMID: 25052253 PMCID: PMC4141111 DOI: 10.1186/1471-2164-15-625] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 07/10/2014] [Indexed: 01/02/2023] Open
Abstract
Background The domestic goat (Capra hircus), an important livestock species, belongs to a clade of Ruminantia, Bovidae, together with cattle, buffalo and sheep. The history of genome evolution and chromosomal rearrangements on a small scale in ruminants remain speculative. Recently completed goat genome sequence was released but is still in a draft stage. The draft sequence used a variety of assembly packages, as well as a radiation hybrid (RH) map of chromosome 1 as part of its validation. Results Using an improved RH mapping pipeline, whole-genome dense maps of 45,953 SNP markers were constructed with statistical confidence measures and the saturated maps provided a fine map resolution of approximate 65 kb. Linking RH maps to the goat sequences showed that the assemblies of scaffolds/super-scaffolds were globally accurate. However, we observed certain flaws linked to the process of anchoring chromosome using conserved synteny with cattle. Chromosome assignments, long-range order, and orientation of the scaffolds were reassessed in an updated genome sequence version. We also present new results exploiting the updated goat genome sequence to understand genomic rearrangements and chromosome evolution between mammals during species radiations. The sequence architecture of rearrangement sites between the goat and cattle genomes presented abundant segmental duplication on regions of goat chromosome 9 and 14, as well as new insertions in homologous cattle genome regions. This complex interplay between duplicated sequences and Robertsonian translocations highlights the rearrangement mechanism of centromeric nonallelic homologous recombination (NAHR) in mammals. We observed that species-specific shifts in ANKRD26 gene duplication are coincident with breakpoint reuse in divergent lineages and this gene family may play a role in chromosome stabilization in chromosome evolution. Conclusions We generated dense maps of the complete whole goat genome. The chromosomal maps allowed us to anchor and orientate assembled genome scaffolds along the chromosomes, annotate chromosome rearrangements and thereby get a better understanding of the genome evolution of ruminants and other mammals. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-625) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | - Wen Wang
- Key lab of animal genetics, breeding and reproduction of ministry education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
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Li Y, Lancaster ML, Carthew SM, Packer JG, Cooper SJB. Delineation of conservation units in an endangered marsupial, the southern brown bandicoot (Isoodon obesulus obesulus), in South Australia/western Victoria, Australia. AUST J ZOOL 2014. [DOI: 10.1071/zo14038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Conservation programs for threatened species are greatly benefiting from genetic data, for their power in providing knowledge of dispersal/gene flow across fragmented landscapes and for identifying populations of high conservation value. The endangered southern brown bandicoot (Isoodon obesulus obesulus) has a disjunct distribution range in South Australia, raising the possibility that populations of the subspecies may represent distinct conservation units. In the current study, we used a combination of 14 microsatellite and two mitochondrial sequence markers to investigate the phylogeography and population structure of I. o. obesulus in South Australia and south-western Victoria, with the aim of identifying any potential evolutionarily significant units and management units relevant to conservation management. Our phylogenetic/population analyses supported the presence of two distinct evolutionary lineages of I. o. obesulus. The first lineage comprised individuals from the Mount Lofty Ranges, Fleurieu Peninsula and Kangaroo Island. A second lineage comprised individuals from the south-east of South Australia and south-western Victoria. We propose that these two lineages represent distinct evolutionarily significant units and should be managed separately for conservation purposes. The findings also raise significant issues for the national conservation status of I. o. obesulus and suggest that the current subspecies classification needs further investigation.
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Andreyenkova NG, Kolesnikova TD, Makunin IV, Pokholkova GV, Boldyreva LV, Zykova TY, Zhimulev IF, Belyaeva ES. Late replication domains are evolutionary conserved in the Drosophila genome. PLoS One 2013; 8:e83319. [PMID: 24391753 PMCID: PMC3877026 DOI: 10.1371/journal.pone.0083319] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 11/01/2013] [Indexed: 12/20/2022] Open
Abstract
Drosophila chromosomes are organized into distinct domains differing in their predominant chromatin composition, replication timing and evolutionary conservation. We show on a genome-wide level that genes whose order has remained unaltered across 9 Drosophila species display late replication timing and frequently map to the regions of repressive chromatin. This observation is consistent with the existence of extensive domains of repressive chromatin that replicate extremely late and have conserved gene order in the Drosophila genome. We suggest that such repressive chromatin domains correspond to a handful of regions that complete replication at the very end of S phase. We further demonstrate that the order of genes in these regions is rarely altered in evolution. Substantial proportion of such regions significantly coincide with large synteny blocks. This indicates that there are evolutionary mechanisms maintaining the integrity of these late-replicating chromatin domains. The synteny blocks corresponding to the extremely late-replicating regions in the D. melanogaster genome consistently display two-fold lower gene density across different Drosophila species.
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Affiliation(s)
- Natalya G. Andreyenkova
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Tatyana D. Kolesnikova
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Igor V. Makunin
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- Research Computing Centre, The University of Queensland, Brisbane, St Lucia, QLD, Australia
| | - Galina V. Pokholkova
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Lidiya V. Boldyreva
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Tatyana Yu. Zykova
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Igor F. Zhimulev
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- * E-mail:
| | - Elena S. Belyaeva
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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Deakin JE, Delbridge ML, Koina E, Harley N, Alsop AE, Wang C, Patel VS, Graves JAM. Reconstruction of the ancestral marsupial karyotype from comparative gene maps. BMC Evol Biol 2013; 13:258. [PMID: 24261750 PMCID: PMC4222502 DOI: 10.1186/1471-2148-13-258] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 11/19/2013] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND The increasing number of assembled mammalian genomes makes it possible to compare genome organisation across mammalian lineages and reconstruct chromosomes of the ancestral marsupial and therian (marsupial and eutherian) mammals. However, the reconstruction of ancestral genomes requires genome assemblies to be anchored to chromosomes. The recently sequenced tammar wallaby (Macropus eugenii) genome was assembled into over 300,000 contigs. We previously devised an efficient strategy for mapping large evolutionarily conserved blocks in non-model mammals, and applied this to determine the arrangement of conserved blocks on all wallaby chromosomes, thereby permitting comparative maps to be constructed and resolve the long debated issue between a 2n = 14 and 2n = 22 ancestral marsupial karyotype. RESULTS We identified large blocks of genes conserved between human and opossum, and mapped genes corresponding to the ends of these blocks by fluorescence in situ hybridization (FISH). A total of 242 genes was assigned to wallaby chromosomes in the present study, bringing the total number of genes mapped to 554 and making it the most densely cytogenetically mapped marsupial genome. We used these gene assignments to construct comparative maps between wallaby and opossum, which uncovered many intrachromosomal rearrangements, particularly for genes found on wallaby chromosomes X and 3. Expanding comparisons to include chicken and human permitted the putative ancestral marsupial (2n = 14) and therian mammal (2n = 19) karyotypes to be reconstructed. CONCLUSIONS Our physical mapping data for the tammar wallaby has uncovered the events shaping marsupial genomes and enabled us to predict the ancestral marsupial karyotype, supporting a 2n = 14 ancestor. Futhermore, our predicted therian ancestral karyotype has helped to understand the evolution of the ancestral eutherian genome.
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Affiliation(s)
- Janine E Deakin
- ARC Centre of Excellence for Kangaroo Genomics, Canberra, Australia.
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Affiliation(s)
- Jennifer A. Marshall Graves
- La Trobe Institute of Molecular Sciences, La Trobe University, Melbourne 3186, Australia
- Research School of Biology, Australian National University, Canberra 2060, Australia;
- Department of Zoology, University of Melbourne, Melbourne 3010, Australia
| | - Marilyn B. Renfree
- Department of Zoology, University of Melbourne, Melbourne 3010, Australia
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Phillips MJ, Haouchar D, Pratt RC, Gibb GC, Bunce M. Inferring kangaroo phylogeny from incongruent nuclear and mitochondrial genes. PLoS One 2013; 8:e57745. [PMID: 23451266 PMCID: PMC3579791 DOI: 10.1371/journal.pone.0057745] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 01/24/2013] [Indexed: 11/18/2022] Open
Abstract
The marsupial genus Macropus includes three subgenera, the familiar large grazing kangaroos and wallaroos of M. (Macropus) and M. (Osphranter), as well as the smaller mixed grazing/browsing wallabies of M. (Notamacropus). A recent study of five concatenated nuclear genes recommended subsuming the predominantly browsing Wallabia bicolor (swamp wallaby) into Macropus. To further examine this proposal we sequenced partial mitochondrial genomes for kangaroos and wallabies. These sequences strongly favour the morphological placement of W. bicolor as sister to Macropus, although place M. irma (black-gloved wallaby) within M. (Osphranter) rather than as expected, with M. (Notamacropus). Species tree estimation from separately analysed mitochondrial and nuclear genes favours retaining Macropus and Wallabia as separate genera. A simulation study finds that incomplete lineage sorting among nuclear genes is a plausible explanation for incongruence with the mitochondrial placement of W. bicolor, while mitochondrial introgression from a wallaroo into M. irma is the deepest such event identified in marsupials. Similar such coalescent simulations for interpreting gene tree conflicts will increase in both relevance and statistical power as species-level phylogenetics enters the genomic age. Ecological considerations in turn, hint at a role for selection in accelerating the fixation of introgressed or incompletely sorted loci. More generally the inclusion of the mitochondrial sequences substantially enhanced phylogenetic resolution. However, we caution that the evolutionary dynamics that enhance mitochondria as speciation indicators in the presence of incomplete lineage sorting may also render them especially susceptible to introgression.
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Affiliation(s)
- Matthew J Phillips
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia.
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Graves JAM. Kangaroo gene mapping and sequencing: insights into mammalian genome evolution. AUST J ZOOL 2013. [DOI: 10.1071/zo13002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The deep divergence of marsupials and eutherian mammals 160 million years ago provides genetic variation to explore the evolution of DNA sequence, gene arrangement and regulation of gene expression in mammals. Following the pioneering work of Professor Desmond W. Cooper, emerging techniques in cytogenetics and molecular biology have been adapted to characterise the genomes of kangaroos and other marsupials. In particular, genetic and genomic work over four decades has shown that marsupial sex chromosomes differ significantly from the eutherian XY chromosome pair in their size, gene content and activity. These differences can be exploited to deduce how mammalian sex chromosomes, sex determination and epigenetic silencing evolved.
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Lindsay J, Carone DM, Brown J, Hall L, Qureshi S, Mitchell SE, Jannetty N, Hannon G, Renfree M, Pask A, O'Neill M, O'Neill R. Unique small RNA signatures uncovered in the tammar wallaby genome. BMC Genomics 2012; 13:559. [PMID: 23075437 PMCID: PMC3576234 DOI: 10.1186/1471-2164-13-559] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 10/08/2012] [Indexed: 12/12/2022] Open
Abstract
Background Small RNAs have proven to be essential regulatory molecules encoded within eukaryotic genomes. These short RNAs participate in a diverse array of cellular processes including gene regulation, chromatin dynamics and genome defense. The tammar wallaby, a marsupial mammal, is a powerful comparative model for studying the evolution of regulatory networks. As part of the genome sequencing initiative for the tammar, we have explored the evolution of each of the major classes of mammalian small RNAs in an Australian marsupial for the first time, including the first genome-scale analysis of the newest class of small RNAs, centromere repeat associated short interacting RNAs (crasiRNAs). Results Using next generation sequencing, we have characterized the major classes of small RNAs, micro (mi) RNAs, piwi interacting (pi) RNAs, and the centromere repeat associated short interacting (crasi) RNAs in the tammar. We examined each of these small RNA classes with respect to the newly assembled tammar wallaby genome for gene and repeat features, salient features that define their canonical sequences, and the constitution of both highly conserved and species-specific members. Using a combination of miRNA hairpin predictions and co-mapping with miRBase entries, we identified a highly conserved cluster of miRNA genes on the X chromosome in the tammar and a total of 94 other predicted miRNA producing genes. Mapping all miRNAs to the tammar genome and comparing target genes among tammar, mouse and human, we identified 163 conserved target genes. An additional nine genes were identified in tammar that do not have an orthologous miRNA target in human and likely represent novel miRNA-regulated genes in the tammar. A survey of the tammar gonadal piRNAs shows that these small RNAs are enriched in retroelements and carry members from both marsupial and tammar-specific repeat classes. Lastly, this study includes the first in-depth analyses of the newly discovered crasiRNAs. These small RNAs are derived largely from centromere-enriched retroelements, including a novel SINE. Conclusions This study encompasses the first analyses of the major classes of small RNAs for the newly completed tammar genome, validates preliminary annotations using deep sequencing and computational approaches, and provides a foundation for future work on tammar-specific as well as conserved, but previously unknown small RNA progenitors and targets identified herein. The characterization of new miRNA target genes and a unique profile for crasiRNAs has allowed for insight into multiple RNA mediated processes in the tammar, including gene regulation, species incompatibilities, centromere and chromosome function.
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Affiliation(s)
- James Lindsay
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA
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Frankham GJ, Handasyde KA, Eldridge MD. Novel insights into the phylogenetic relationships of the endangered marsupial genus Potorous. Mol Phylogenet Evol 2012; 64:592-602. [DOI: 10.1016/j.ympev.2012.05.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 05/04/2012] [Accepted: 05/15/2012] [Indexed: 11/16/2022]
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Satellite DNA-like elements associated with genes within euchromatin of the beetle Tribolium castaneum. G3-GENES GENOMES GENETICS 2012; 2:931-41. [PMID: 22908042 PMCID: PMC3411249 DOI: 10.1534/g3.112.003467] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 06/18/2012] [Indexed: 01/30/2023]
Abstract
In the red flour beetle Tribolium castaneum the major TCAST satellite DNA accounts for 35% of the genome and encompasses the pericentromeric regions of all chromosomes. Because of the presence of transcriptional regulatory elements and transcriptional activity in these sequences, TCAST satellite DNAs also have been proposed to be modulators of gene expression within euchromatin. Here, we analyze the distribution of TCAST homologous repeats in T. castaneum euchromatin and study their association with genes as well as their potential gene regulatory role. We identified 68 arrays composed of TCAST-like elements distributed on all chromosomes. Based on sequence characteristics the arrays were composed of two types of TCAST-like elements. The first type consists of TCAST satellite-like elements in the form of partial monomers or tandemly arranged monomers, up to tetramers, whereas the second type consists of TCAST-like elements embedded with a complex unit that resembles a DNA transposon. TCAST-like elements were also found in the 5′ untranslated region (UTR) of the CR1-3_TCa retrotransposon, and therefore retrotransposition may have contributed to their dispersion throughout the genome. No significant difference in the homogenization of dispersed TCAST-like elements was found either at the level of local arrays or chromosomes nor among different chromosomes. Of 68 TCAST-like elements, 29 were located within introns, with the remaining elements flanked by genes within a 262 to 404,270 nt range. TCAST-like elements are statistically overrepresented near genes with immunoglobulin-like domains attesting to their nonrandom distribution and a possible gene regulatory role.
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Deakin JE, Graves JAM, Rens W. The evolution of marsupial and monotreme chromosomes. Cytogenet Genome Res 2012; 137:113-29. [PMID: 22777195 DOI: 10.1159/000339433] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Marsupial and monotreme mammals fill an important gap in vertebrate phylogeny between reptile-mammal divergence 310 million years ago (mya) and the eutherian (placental) mammal radiation 105 mya. They possess many unique features including their distinctive chromosomes, which in marsupials are typically very large and well conserved between species. In contrast, monotreme genomes are divided into several large chromosomes and many smaller chromosomes, with a complicated sex chromosome system that forms a translocation chain in male meiosis. The application of molecular cytogenetic techniques has greatly advanced our understanding of the evolution of marsupial chromosomes and allowed the reconstruction of the ancestral marsupial karyotype. Chromosome painting and gene mapping have played a vital role in piecing together the puzzle of monotreme karyotypes, particularly their complicated sex chromosome system. Here, we discuss the significant insight into karyotype evolution afforded by the combination of recently sequenced marsupial and monotreme genomes with cytogenetic analysis, which has provided a greater understanding of the events that have shaped not only marsupial and monotreme genomes, but the genomes of all mammals.
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Affiliation(s)
- J E Deakin
- Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Canberra, ACT, Australia.
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Bakloushinskaya IY, Matveevsky SN, Romanenko SA, Serdukova NA, Kolomiets OL, Spangenberg VE, Lyapunova EA, Graphodatsky AS. A comparative analysis of the mole vole sibling species Ellobius tancrei and E. talpinus (Cricetidae, Rodentia) through chromosome painting and examination of synaptonemal complex structures in hybrids. Cytogenet Genome Res 2012; 136:199-207. [PMID: 22343488 DOI: 10.1159/000336459] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2012] [Indexed: 12/27/2022] Open
Abstract
A comparative genomic analysis was carried out in the mole vole sibling species Ellobius tancrei and E. talpinus. Performing fluorescent in situ hybridisation (Zoo-FISH) using chromosome paints from the field vole Microtus agrestis showed no differences in the allocation of syntenic groups in the karyotypes of these sibling species. The only difference between their karyotypes was the position of the centromere in one pair of chromosomes, which is assumed to be the result of an inversion. To verify this hypothesis, we analysed chromosome synapsis in prophase I of meiosis. We utilised a synaptonemal complex (SC) surface-spreading technique to visualise the process of chromosome synapsis in the spermatocytes and oocytes of first-generation hybrids and back-crosses of these sibling species. In prophase I of meiosis, immunocytochemical and electron microscopy analyses revealed that all bivalents had been fully adjusted. Even in the case of a submetacentric-acrocentric bivalent with different centromere locations, synapsis of SC lateral elements was fulfilled along the entire length of the chromosomes and the formation of an inversion loop was not observed. We hypothesise that a possible mechanism leading to the change in centromere position is the repositioning and/or generation of a neocentromere. Despite the great similarity in the karyotypes of these sibling species, they exhibited significant genomic diversification, which manifested as hybrid sterility and parous female death.
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Affiliation(s)
- I Yu Bakloushinskaya
- Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia.
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38
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Potter S, Cooper SJ, Metcalfe CJ, Taggart DA, Eldridge MD. Phylogenetic relationships of rock-wallabies, Petrogale (Marsupialia: Macropodidae) and their biogeographic history within Australia. Mol Phylogenet Evol 2012; 62:640-52. [DOI: 10.1016/j.ympev.2011.11.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Revised: 10/20/2011] [Accepted: 11/08/2011] [Indexed: 11/24/2022]
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Brown JD, Mitchell SE, O'Neill RJ. Making a long story short: noncoding RNAs and chromosome change. Heredity (Edinb) 2011; 108:42-9. [PMID: 22072070 DOI: 10.1038/hdy.2011.104] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
As important as the events that influence selection for specific chromosome types in the derivation of novel karyotypes, are the events that initiate the changes in chromosome number and structure between species, and likewise polymorphisms, variants and disease states within species. Although once thought of as transcriptional 'noise', noncoding RNAs (ncRNAs) are now recognized as important mediators of epigenetic regulation and chromosome stability. Here we highlight recent work that illustrates the influence short and long ncRNAs have as participants in the function and stability of chromosome regions such as centromeres, telomeres, evolutionary breakpoints and fragile sites. We summarize recent evidence that ncRNAs can facilitate chromosome change and present mechanisms by which ncRNAs create DNA breaks. Finally, we present hypotheses on how they may create novel karyotypes and thus affect chromosome evolution.
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Affiliation(s)
- J D Brown
- Allied Health Sciences Department, University of Connecticut, Storrs, CT, USA
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40
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Renfree MB, Papenfuss AT, Deakin JE, Lindsay J, Heider T, Belov K, Rens W, Waters PD, Pharo EA, Shaw G, Wong ESW, Lefèvre CM, Nicholas KR, Kuroki Y, Wakefield MJ, Zenger KR, Wang C, Ferguson-Smith M, Nicholas FW, Hickford D, Yu H, Short KR, Siddle HV, Frankenberg SR, Chew KY, Menzies BR, Stringer JM, Suzuki S, Hore TA, Delbridge ML, Mohammadi A, Schneider NY, Hu Y, O'Hara W, Al Nadaf S, Wu C, Feng ZP, Cocks BG, Wang J, Flicek P, Searle SMJ, Fairley S, Beal K, Herrero J, Carone DM, Suzuki Y, Sugano S, Toyoda A, Sakaki Y, Kondo S, Nishida Y, Tatsumoto S, Mandiou I, Hsu A, McColl KA, Lansdell B, Weinstock G, Kuczek E, McGrath A, Wilson P, Men A, Hazar-Rethinam M, Hall A, Davis J, Wood D, Williams S, Sundaravadanam Y, Muzny DM, Jhangiani SN, Lewis LR, Morgan MB, Okwuonu GO, Ruiz SJ, Santibanez J, Nazareth L, Cree A, Fowler G, Kovar CL, Dinh HH, Joshi V, Jing C, Lara F, Thornton R, Chen L, Deng J, Liu Y, Shen JY, Song XZ, Edson J, Troon C, Thomas D, Stephens A, Yapa L, Levchenko T, Gibbs RA, Cooper DW, Speed TP, Fujiyama A, M Graves JA, O'Neill RJ, Pask AJ, Forrest SM, Worley KC. Genome sequence of an Australian kangaroo, Macropus eugenii, provides insight into the evolution of mammalian reproduction and development. Genome Biol 2011; 12:R81. [PMID: 21854559 PMCID: PMC3277949 DOI: 10.1186/gb-2011-12-8-r81] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/22/2011] [Accepted: 08/19/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. RESULTS The genome has been sequenced to 2 × coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. CONCLUSIONS Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution.
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Affiliation(s)
- Marilyn B Renfree
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Anthony T Papenfuss
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Mathematics and Statistics, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Janine E Deakin
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - James Lindsay
- Department of Molecular and Cell Biology, Center for Applied Genetics and Technology, University of Connecticut, Storrs, CT 06269, USA
| | - Thomas Heider
- Department of Molecular and Cell Biology, Center for Applied Genetics and Technology, University of Connecticut, Storrs, CT 06269, USA
| | - Katherine Belov
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Faculty of Veterinary Science, University of Sydney, Sydney, NSW 2006, Australia
| | - Willem Rens
- Department of Veterinary Medicine, University of Cambridge, Madingley Rd, Cambridge, CB3 0ES, UK
| | - Paul D Waters
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - Elizabeth A Pharo
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Geoff Shaw
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Emily SW Wong
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Faculty of Veterinary Science, University of Sydney, Sydney, NSW 2006, Australia
| | - Christophe M Lefèvre
- Institute for Technology Research and Innovation, Deakin University, Geelong, Victoria, 3214, Australia
| | - Kevin R Nicholas
- Institute for Technology Research and Innovation, Deakin University, Geelong, Victoria, 3214, Australia
| | - Yoko Kuroki
- RIKEN Institute, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Matthew J Wakefield
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Kyall R Zenger
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Faculty of Veterinary Science, University of Sydney, Sydney, NSW 2006, Australia
- School of Marine and Tropical Biology, James Cook University, Townsville, Queensland 4811, Australia
| | - Chenwei Wang
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Faculty of Veterinary Science, University of Sydney, Sydney, NSW 2006, Australia
| | - Malcolm Ferguson-Smith
- Department of Veterinary Medicine, University of Cambridge, Madingley Rd, Cambridge, CB3 0ES, UK
| | - Frank W Nicholas
- Faculty of Veterinary Science, University of Sydney, Sydney, NSW 2006, Australia
| | - Danielle Hickford
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Hongshi Yu
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Kirsty R Short
- Department of Microbiology and Immunology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Hannah V Siddle
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Faculty of Veterinary Science, University of Sydney, Sydney, NSW 2006, Australia
| | - Stephen R Frankenberg
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Keng Yih Chew
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Brandon R Menzies
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, Berlin 10315, Germany
| | - Jessica M Stringer
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Shunsuke Suzuki
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Timothy A Hore
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Laboratory of Developmental Genetics and Imprinting, The Babraham Institute, Cambridge, CB22 3AT, UK
| | - Margaret L Delbridge
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - Amir Mohammadi
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - Nanette Y Schneider
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Department of Molecular Genetics, German Institute of Human Nutrition, Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany
| | - Yanqiu Hu
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - William O'Hara
- Department of Molecular and Cell Biology, Center for Applied Genetics and Technology, University of Connecticut, Storrs, CT 06269, USA
| | - Shafagh Al Nadaf
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - Chen Wu
- Faculty of Veterinary Science, University of Sydney, Sydney, NSW 2006, Australia
| | - Zhi-Ping Feng
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Benjamin G Cocks
- Biosciences Research Division, Department of Primary Industries, Victoria, 1 Park Drive, Bundoora 3083, Australia
| | - Jianghui Wang
- Biosciences Research Division, Department of Primary Industries, Victoria, 1 Park Drive, Bundoora 3083, Australia
| | - Paul Flicek
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Stephen MJ Searle
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Susan Fairley
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Kathryn Beal
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Javier Herrero
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Dawn M Carone
- Department of Molecular and Cell Biology, Center for Applied Genetics and Technology, University of Connecticut, Storrs, CT 06269, USA
- Department of Cell Biology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Yutaka Suzuki
- Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8560, Japan
| | - Sumio Sugano
- Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8560, Japan
| | - Atsushi Toyoda
- National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Yoshiyuki Sakaki
- RIKEN Institute, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Shinji Kondo
- RIKEN Institute, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Yuichiro Nishida
- RIKEN Institute, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Shoji Tatsumoto
- RIKEN Institute, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Ion Mandiou
- Department of Computer Science and Engineering, University of Connecticut, Storrs, CT 06269, USA
| | - Arthur Hsu
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Kaighin A McColl
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Benjamin Lansdell
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - George Weinstock
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Elizabeth Kuczek
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
- Westmead Institute for Cancer Research, University of Sydney, Westmead, New South Wales 2145, Australia
| | - Annette McGrath
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Peter Wilson
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Artem Men
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Mehlika Hazar-Rethinam
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Allison Hall
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - John Davis
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - David Wood
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Sarah Williams
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Yogi Sundaravadanam
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Donna M Muzny
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Shalini N Jhangiani
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Lora R Lewis
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Margaret B Morgan
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Geoffrey O Okwuonu
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - San Juana Ruiz
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Jireh Santibanez
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Lynne Nazareth
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Andrew Cree
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Gerald Fowler
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Christie L Kovar
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Huyen H Dinh
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Vandita Joshi
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Chyn Jing
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Fremiet Lara
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Rebecca Thornton
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Lei Chen
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Jixin Deng
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Yue Liu
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Joshua Y Shen
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Xing-Zhi Song
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Janette Edson
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Carmen Troon
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Daniel Thomas
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Amber Stephens
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Lankesha Yapa
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Tanya Levchenko
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Richard A Gibbs
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
| | - Desmond W Cooper
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Terence P Speed
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Asao Fujiyama
- National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430, Japan
| | - Jennifer A M Graves
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - Rachel J O'Neill
- Department of Molecular and Cell Biology, Center for Applied Genetics and Technology, University of Connecticut, Storrs, CT 06269, USA
| | - Andrew J Pask
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Department of Zoology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Department of Molecular and Cell Biology, Center for Applied Genetics and Technology, University of Connecticut, Storrs, CT 06269, USA
| | - Susan M Forrest
- The Australian Research Council Centre of Excellence in Kangaroo Genomics, Australia
- Australian Genome Research Facility, Melbourne, Victoria, 3052 and the University of Queensland, St Lucia, Queensland 4072, Australia
| | - Kim C Worley
- Human Genome Sequencing Center, Department of Molecular and Human Genetics Baylor College of Medicine, Houston, TX 77030, USA
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41
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Brown JD, Carone DM, Flynn BL, Finn CE, Mlynarski EE, O'Neill RJ. Centromere conversion and retention in somatic cell hybrids. Cytogenet Genome Res 2011; 134:182-90. [PMID: 21709412 DOI: 10.1159/000328830] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/28/2011] [Indexed: 01/20/2023] Open
Abstract
The generation of somatic cell hybridization-derived cell lines between highly divergent species affords the opportunity to examine the concept of 'genome dominance' in the context of genetic and epigenetic changes. While whole-scale genome dominance has been well documented in natural hybrids among closely related species, an examination of centromere position and sequence retention in 2 marsupial-eutherian hybrids has revealed a mechanism for 'centromere dominance' as a driving force in the generation of stable somatic cell hybrids following an initial period of genomic instability. While one somatic cell hybrid cell line appeared to retain marsupial centromere sequences which remained competent to recruit the centromere-specific histone variant CENP-A in a Chinese hamster background, fusion events between marsupial and mouse-derived chromosomes in another hybrid line led to a centromere sequence conversion from one species to the other. We postulate that the necessity to maintain an epigenetically defined centromere following genome hybridization may be responsible for retention of specific chromosomes and may result in rapid sequence turnover to facilitate the recruitment of CENP-A containing histones.
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Affiliation(s)
- J D Brown
- Department of Allied Health Sciences, University of Connecticut, Storrs, CT 06269, USA
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42
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Recent amplification of the kangaroo endogenous retrovirus, KERV, limited to the centromere. J Virol 2011; 85:4761-71. [PMID: 21389136 DOI: 10.1128/jvi.01604-10] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mammalian retrotransposons, transposable elements that are processed through an RNA intermediate, are categorized as short interspersed elements (SINEs), long interspersed elements (LINEs), and long terminal repeat (LTR) retroelements, which include endogenous retroviruses. The ability of transposable elements to autonomously amplify led to their initial characterization as selfish or junk DNA; however, it is now known that they may acquire specific cellular functions in a genome and are implicated in host defense mechanisms as well as in genome evolution. Interactions between classes of transposable elements may exert a markedly different and potentially more significant effect on a genome than interactions between members of a single class of transposable elements. We examined the genomic structure and evolution of the kangaroo endogenous retrovirus (KERV) in the marsupial genus Macropus. The complete proviral structure of the kangaroo endogenous retrovirus, phylogenetic relationship among relative retroviruses, and expression of this virus in both Macropus rufogriseus and M. eugenii are presented for the first time. In addition, we show the relative copy number and distribution of the kangaroo endogenous retrovirus in the Macropus genus. Our data indicate that amplification of the kangaroo endogenous retrovirus occurred in a lineage-specific fashion, is restricted to the centromeres, and is not correlated with LINE depletion. Finally, analysis of KERV long terminal repeat sequences using massively parallel sequencing indicates that the recent amplification in M. rufogriseus is likely due to duplications and concerted evolution rather than a high number of independent insertion events.
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43
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Eldridge MDB, Heckenberg K, Neaves LE, Metcalfe CJ, Hamilton S, Johnson PM, Close RL. Genetic differentiation and introgression amongst Thylogale (pademelons) taxa in eastern Australia. AUST J ZOOL 2011. [DOI: 10.1071/zo11022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Although pademelons (Thylogale) are widespread and common in coastal eastern Australia, they have been largely neglected in population genetic studies. Here we use 10 microsatellite loci and the mitochondrial DNA (mtDNA) cytochrome b (Cytb) gene to examine genetic differentiation amongst populations of the red-necked (Thylogale thetis) and red-legged (T. stigmatica) pademelon in eastern Australia. Evidence of hybridisation was detected between subspecies of T. stigmatica in central Queensland. Specimens sampled between Eungella and Sarina were found to represent a broad (~90 km) zone of introgression, for both nuclear and mtDNA markers, between T. s. stigmatica (Wet Tropics) and T. s. wilcoxi (south-east Queensland). In addition, individuals sampled from around Proserpine were genetically T. s. stigmatica rather than T. s. wilcoxi, as had previously been assumed. This observation raises some intriguing questions about the dispersal ability of T. stigmatica and the phylogeographic history of moist forest taxa in eastern Australia. Only limited evidence of introgression was detected between sympatric populations of T. thetis and T. s. wilcoxi in south-east Queensland.
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44
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Phylogenetics of the pademelons (Macropodidae: Thylogale) and historical biogeography of the Australo-Papuan region. Mol Phylogenet Evol 2010; 57:1134-48. [DOI: 10.1016/j.ympev.2010.08.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 05/23/2010] [Accepted: 08/09/2010] [Indexed: 11/24/2022]
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45
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Alkan C, Cardone MF, Catacchio CR, Antonacci F, O'Brien SJ, Ryder OA, Purgato S, Zoli M, Della Valle G, Eichler EE, Ventura M. Genome-wide characterization of centromeric satellites from multiple mammalian genomes. Genome Res 2010; 21:137-45. [PMID: 21081712 DOI: 10.1101/gr.111278.110] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Despite its importance in cell biology and evolution, the centromere has remained the final frontier in genome assembly and annotation due to its complex repeat structure. However, isolation and characterization of the centromeric repeats from newly sequenced species are necessary for a complete understanding of genome evolution and function. In recent years, various genomes have been sequenced, but the characterization of the corresponding centromeric DNA has lagged behind. Here, we present a computational method (RepeatNet) to systematically identify higher-order repeat structures from unassembled whole-genome shotgun sequence and test whether these sequence elements correspond to functional centromeric sequences. We analyzed genome datasets from six species of mammals representing the diversity of the mammalian lineage, namely, horse, dog, elephant, armadillo, opossum, and platypus. We define candidate monomer satellite repeats and demonstrate centromeric localization for five of the six genomes. Our analysis revealed the greatest diversity of centromeric sequences in horse and dog in contrast to elephant and armadillo, which showed high-centromeric sequence homogeneity. We could not isolate centromeric sequences within the platypus genome, suggesting that centromeres in platypus are not enriched in satellite DNA. Our method can be applied to the characterization of thousands of other vertebrate genomes anticipated for sequencing in the near future, providing an important tool for annotation of centromeres.
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Affiliation(s)
- Can Alkan
- Department of Genome Sciences, Howard Hughes Medical Institute, University of Washington School of Medicine, Seattle, Washington 98195, USA
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46
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Murat F, Xu JH, Tannier E, Abrouk M, Guilhot N, Pont C, Messing J, Salse J. Ancestral grass karyotype reconstruction unravels new mechanisms of genome shuffling as a source of plant evolution. Genome Res 2010; 20:1545-57. [PMID: 20876790 PMCID: PMC2963818 DOI: 10.1101/gr.109744.110] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Accepted: 08/24/2010] [Indexed: 11/25/2022]
Abstract
The comparison of the chromosome numbers of today's species with common reconstructed paleo-ancestors has led to intense speculation of how chromosomes have been rearranged over time in mammals. However, similar studies in plants with respect to genome evolution as well as molecular mechanisms leading to mosaic synteny blocks have been lacking due to relevant examples of evolutionary zooms from genomic sequences. Such studies require genomes of species that belong to the same family but are diverged to fall into different subfamilies. Our most important crops belong to the family of the grasses, where a number of genomes have now been sequenced. Based on detailed paleogenomics, using inference from n = 5-12 grass ancestral karyotypes (AGKs) in terms of gene content and order, we delineated sequence intervals comprising a complete set of junction break points of orthologous regions from rice, maize, sorghum, and Brachypodium genomes, representing three different subfamilies and different polyploidization events. By focusing on these sequence intervals, we could show that the chromosome number variation/reduction from the n = 12 common paleo-ancestor was driven by nonrandom centric double-strand break repair events. It appeared that the centromeric/telomeric illegitimate recombination between nonhomologous chromosomes led to nested chromosome fusions (NCFs) and synteny break points (SBPs). When intervals comprising NCFs were compared in their structure, we concluded that SBPs (1) were meiotic recombination hotspots, (2) corresponded to high sequence turnover loci through repeat invasion, and (3) might be considered as hotspots of evolutionary novelty that could act as a reservoir for producing adaptive phenotypes.
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Affiliation(s)
- Florent Murat
- INRA, UMR 1095, Laboratoire Génétique, Diversité et Ecophysiologie des Céréales, 63100 Clermont Ferrand, France
| | - Jian-Hong Xu
- The Plant Genome Initiative at Rutgers (PGIR), Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Eric Tannier
- INRIA Rhône-Alpes, Université de Lyon 1, CNRS UMR5558, Laboratoire Biométrie et Biologie Évolutive, 69622 Villeurbanne Cedex, France
| | - Michael Abrouk
- INRA, UMR 1095, Laboratoire Génétique, Diversité et Ecophysiologie des Céréales, 63100 Clermont Ferrand, France
| | - Nicolas Guilhot
- INRA, UMR 1095, Laboratoire Génétique, Diversité et Ecophysiologie des Céréales, 63100 Clermont Ferrand, France
| | - Caroline Pont
- INRA, UMR 1095, Laboratoire Génétique, Diversité et Ecophysiologie des Céréales, 63100 Clermont Ferrand, France
| | - Joachim Messing
- The Plant Genome Initiative at Rutgers (PGIR), Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Jérôme Salse
- INRA, UMR 1095, Laboratoire Génétique, Diversité et Ecophysiologie des Céréales, 63100 Clermont Ferrand, France
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Westerman M, Meredith RW, Springer MS. Cytogenetics meets phylogenetics: a review of karyotype evolution in diprotodontian marsupials. ACTA ACUST UNITED AC 2010; 101:690-702. [PMID: 20581108 DOI: 10.1093/jhered/esq076] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have used a combined approach of phylogenetics and cytogenetics to describe karyotype evolution in Diprotodontia. Molecular relationships of diprotodontian marsupials have been clarified using a concatenation of 5 nuclear gene sequences from multiple exemplars of all extant genera. Our well-resolved phylogenetic tree has been used as a basis for understanding chromosome evolution both within this Order, as well as in marsupials in general. It is clear that the ancestral marsupial karyotype comprised 14 relatively large chromosomes of the form retained relatively unchanged in caenolestids, microbiotherians, peramelemorphians, vombatids, and pygmy possums. Four pericentric inversions occurred in the ancestral dasyuromorphian (chromosomes 1, 2, 4, and 6) and a different 4 in the ancestral didelphimorphian (chromosomes 1, 3, 5 and 6). Within Diprotodontia, although the ancestral marsupial karyotype has been retained in some families such as the extant wombats and pygmy possums, there have been major karytoypic repatternings early in the evolution of others. Chromosome rearrangements in diprotodontia include centric fissions and fusions, translocations, and centromere shifts. Karyotypic changes are discussed in the context of current hypotheses concerning centromeres, chromosomal fragile sites, and mobile elements in marsupials and the probable repeated involvement of these elements in karyotypic restructuring.
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Affiliation(s)
- Michael Westerman
- Genetics Department, La Trobe University, Bundoora, Victoria 3086, Australia
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48
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Mlynarski EE, Obergfell C, Dewey MJ, O'Neill RJ. A unique late-replicating XY to autosome translocation in Peromyscus melanophrys. Chromosome Res 2010; 18:179-89. [PMID: 20177772 DOI: 10.1007/s10577-010-9113-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Accepted: 01/15/2010] [Indexed: 11/25/2022]
Abstract
We report on the characterization of the Peromyscus melanophrys karyotype and sex chromosome system. Classic studies reported the sex chromosome system of this species may be as complex as an X(1)X(1)X(2)X(2)/X(1)X(2)Y(1)Y(2) and provided conflicting identification of the X chromosome. Using Peromyscus maniculatus chromosome paints, we have positively identified the sex chromosomes and clarified the sex determining system that once perplexed Peromyscus researchers. The sex chromosomes are characterized by a unique autosomal translocation of DNA shared between both the X and Y chromosomes. The translocated material is late replicating and heterochromatic yet retains the active chromatin conformation. Thus, autosomal regions derived from translocations involving repeat-rich material may retain some epigenetic marks specific to the sex chromosomes despite loss of epigenetic silencing activity.
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Affiliation(s)
- Elisabeth E Mlynarski
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, 06269, USA
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49
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Divergent patterns of breakpoint reuse in Muroid rodents. Mamm Genome 2009; 21:77-87. [PMID: 20033182 DOI: 10.1007/s00335-009-9242-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Accepted: 11/09/2009] [Indexed: 01/09/2023]
Abstract
Multiple Genome Rearrangement (MGR) analysis was used to define the trajectory and pattern of chromosome rearrangement within muroid rodents. MGR was applied using 107 chromosome homologies between Mus, Rattus, Peromyscus, the muroid sister taxon Cricetulus griseus, and Sciurus carolinensis as a non-Muroidea outgroup, with specific attention paid to breakpoint reuse and centromere evolution. This analysis revealed a high level of chromosome breakpoint conservation between Rattus and Peromyscus and indicated that the chromosomes of Mus are highly derived. This analysis identified several conserved evolutionary breakpoints that have been reused multiple times during karyotypic evolution in rodents. Our data demonstrate a high level of reuse of breakpoints among muroid rodents, further supporting the "Fragile Breakage Model" of chromosome evolution. We provide the first analysis of rodent centromeres with respect to evolutionary breakpoints. By analyzing closely related rodent species we were able to clarify muroid rodent karyotypic evolution. We were also able to derive several high-resolution ancestral karyotypes and identify rearrangements specific to various stages of Muroidea evolution. These data were useful in further characterizing lineage-specific modes of chromosome evolution.
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50
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Distinct retroelement classes define evolutionary breakpoints demarcating sites of evolutionary novelty. BMC Genomics 2009; 10:334. [PMID: 19630942 PMCID: PMC2736999 DOI: 10.1186/1471-2164-10-334] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Accepted: 07/24/2009] [Indexed: 11/30/2022] Open
Abstract
Background Large-scale genome rearrangements brought about by chromosome breaks underlie numerous inherited diseases, initiate or promote many cancers and are also associated with karyotype diversification during species evolution. Recent research has shown that these breakpoints are nonrandomly distributed throughout the mammalian genome and many, termed "evolutionary breakpoints" (EB), are specific genomic locations that are "reused" during karyotypic evolution. When the phylogenetic trajectory of orthologous chromosome segments is considered, many of these EB are coincident with ancient centromere activity as well as new centromere formation. While EB have been characterized as repeat-rich regions, it has not been determined whether specific sequences have been retained during evolution that would indicate previous centromere activity or a propensity for new centromere formation. Likewise, the conservation of specific sequence motifs or classes at EBs among divergent mammalian taxa has not been determined. Results To define conserved sequence features of EBs associated with centromere evolution, we performed comparative sequence analysis of more than 4.8 Mb within the tammar wallaby, Macropus eugenii, derived from centromeric regions (CEN), euchromatic regions (EU), and an evolutionary breakpoint (EB) that has undergone convergent breakpoint reuse and past centromere activity in marsupials. We found a dramatic enrichment for long interspersed nucleotide elements (LINE1s) and endogenous retroviruses (ERVs) and a depletion of short interspersed nucleotide elements (SINEs) shared between CEN and EBs. We analyzed the orthologous human EB (14q32.33), known to be associated with translocations in many cancers including multiple myelomas and plasma cell leukemias, and found a conserved distribution of similar repetitive elements. Conclusion Our data indicate that EBs tracked within the class Mammalia harbor sequence features retained since the divergence of marsupials and eutherians that may have predisposed these genomic regions to large-scale chromosomal instability.
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