Author
Andrew J Pask
Other affiliations: Baylor College of Medicine, Australian Research Council, University of Connecticut ...read more
Bio: Andrew J Pask is an academic researcher from University of Melbourne. The author has contributed to research in topics: Marsupial & Tammar wallaby. The author has an hindex of 32, co-authored 132 publications receiving 4544 citations. Previous affiliations of Andrew J Pask include Baylor College of Medicine & Australian Research Council.
Papers published on a yearly basis
Papers
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Washington University in St. Louis1, Australian National University2, University of Oxford3, University of Adelaide4, University of Sydney5, Pennsylvania State University6, Wellcome Trust Sanger Institute7, University of Cambridge8, University of Oviedo9, University of Washington10, Walter and Eliza Hall Institute of Medical Research11, Weizmann Institute of Science12, Institute for Systems Biology13, University of Melbourne14, Hudson Institute of Medical Research15, Louisiana State University16, University of Canterbury17, University of Münster18, Howard Hughes Medical Institute19, Monash University20, West Virginia University21, New York University22, Institut national de la recherche agronomique23, Iowa State University24, Broad Institute25
TL;DR: It is found that reptile and platypus venom proteins have been co-opted independently from the same gene families; milk protein genes are conserved despite platypuses laying eggs; and immune gene family expansions are directly related to platypUS biology.
Abstract: We present a draft genome sequence of the platypus, Ornithorhynchus anatinus This monotreme exhibits a fascinating combination of reptilian and mammalian characters For example, platypuses have a coat of fur adapted to an aquatic lifestyle; platypus females lactate, yet lay eggs; and males are equipped with venom similar to that of reptiles Analysis of the first monotreme genome aligned these features with genetic innovations We find that reptile and platypus venom proteins have been co-opted independently from the same gene families; milk protein genes are conserved despite platypuses laying eggs; and immune gene family expansions are directly related to platypus biology Expansions of protein, non-protein-coding RNA and microRNA families, as well as repeat elements, are identified Sequencing of this genome now provides a valuable resource for deep mammalian comparative analyses, as well as for monotreme biology and conservation
653 citations
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TL;DR: This corrects the article to show that the method used to derive the H2O2 “spatially aggregating force” is based on a two-step process, not a single step, like in the previous version of this paper.
Abstract: Nature 453, 175–183 (2008) In this Article, Mikhail Nefedov and Pieter J. de Jong were omitted from the author list.
443 citations
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TL;DR: Comparisons between prototherian and therian mammals provide strong support for the host defence hypothesis and show that the platypus has significantly fewer repeats of certain classes in the regions of the genome that have become imprinted in therian mammal.
Abstract: Background: Genomic imprinting is an epigenetic phenomenon that results in monoallelic gene expression. Many hypotheses have been advanced to explain why genomic imprinting evolved in mammals, but few have examined how it arose. The host defence hypothesis suggests that imprinting evolved from existing mechanisms within the cell that act to silence foreign DNA elements that insert into the genome. However, the changes to the mammalian genome that accompanied the evolution of imprinting have been hard to define due to the absence of large scale genomic resources between all extant classes. The recent release of the platypus genome has provided the first opportunity to perform comparisons between prototherian (monotreme; which appear to lack imprinting) and therian (marsupial and eutherian; which have imprinting) mammals. Results: We compared the distribution of repeat elements known to attract epigenetic silencing across the entire genome from monotremes and therian mammals, particularly focusing on the orthologous imprinted regions. There is a significant accumulation of certain repeat elements within imprinted regions of therian mammals compared to the platypus. Conclusions: Our analyses show that the platypus has significantly fewer repeats of certain classes in the regions of the genome that have become imprinted in therian mammals. The accumulation of repeats, especially long terminal repeats and DNA elements, in therian imprinted genes and gene clusters is coincident with, and may have been a potential driving force in, the development of mammalian genomic imprinting. These data provide strong support for the host defence hypothesis.
246 citations
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TL;DR: It is provided the first demonstration that DMR-associated genomic imprinting in eutherians can originate from the repression of exogenous DNA sequences and/or retrotransposons by DNA methylation.
Abstract: Among mammals, only eutherians and marsupials are viviparous and have genomic imprinting that leads to parent-of-origin-specific differential gene expression. We used comparative analysis to investigate the origin of genomic imprinting in mammals. PEG10 (paternally expressed 10) is a retrotransposon-derived imprinted gene that has an essential role for the formation of the placenta of the mouse. Here, we show that an orthologue of PEG10 exists in another therian mammal, the marsupial tammar wallaby (Macropus eugenii), but not in a prototherian mammal, the egg-laying platypus (Ornithorhynchus anatinus), suggesting its close relationship to the origin of placentation in therian mammals. We have discovered a hitherto missing link of the imprinting mechanism between eutherians and marsupials because tammar PEG10 is the first example of a differentially methylated region (DMR) associated with genomic imprinting in marsupials. Surprisingly, the marsupial DMR was strictly limited to the 5' region of PEG10, unlike the eutherian DMR, which covers the promoter regions of both PEG10 and the adjacent imprinted gene SGCE. These results not only demonstrate a common origin of the DMR-associated imprinting mechanism in therian mammals but provide the first demonstration that DMR-associated genomic imprinting in eutherians can originate from the repression of exogenous DNA sequences and/or retrotransposons by DNA methylation.
200 citations
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University of Melbourne1, Australian Research Council2, Walter and Eliza Hall Institute of Medical Research3, Australian National University4, University of Connecticut5, University of Sydney6, University of Cambridge7, Deakin University8, James Cook University9, Leibniz Association10, Babraham Institute11, European Bioinformatics Institute12, Wellcome Trust Sanger Institute13, University of Massachusetts Medical School14, University of Tokyo15, National Institute of Genetics16, Baylor College of Medicine17, University of Queensland18, University of New South Wales19, National Institute of Informatics20
TL;DR: The genome sequence of the tammar wallaby, Macropus eugenii, is presented, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced, to provide new insight into marsupial and mammalian biology and genome evolution.
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.
181 citations
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TL;DR: The evolution of long noncoding RNAs and their roles in transcriptional regulation, epigenetic gene regulation, and disease are reviewed.
4,277 citations
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TL;DR: An increasing body of evidence from animal studies supports the role of environmental epigenetics in disease susceptibility and recent studies have demonstrated for the first time that heritable environmentally induced epigenetic modifications underlie reversible transgenerational alterations in phenotype.
Abstract: Epidemiological evidence increasingly suggests that environmental exposures early in development have a role in susceptibility to disease in later life. In addition, some of these environmental effects seem to be passed on through subsequent generations. Epigenetic modifications provide a plausible link between the environment and alterations in gene expression that might lead to disease phenotypes. An increasing body of evidence from animal studies supports the role of environmental epigenetics in disease susceptibility. Furthermore, recent studies have demonstrated for the first time that heritable environmentally induced epigenetic modifications underlie reversible transgenerational alterations in phenotype. Methods are now becoming available to investigate the relevance of these phenomena to human disease.
2,271 citations
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TL;DR: GO-CAM, a new framework for representing gene function that is more expressive than standard GO annotations, has been released, and users can now explore the growing repository of these models.
Abstract: The Gene Ontology resource (GO; http://geneontology.org) provides structured, computable knowledge regarding the functions of genes and gene products. Founded in 1998, GO has become widely adopted in the life sciences, and its contents are under continual improvement, both in quantity and in quality. Here, we report the major developments of the GO resource during the past two years. Each monthly release of the GO resource is now packaged and given a unique identifier (DOI), enabling GO-based analyses on a specific release to be reproduced in the future. The molecular function ontology has been refactored to better represent the overall activities of gene products, with a focus on transcription regulator activities. Quality assurance efforts have been ramped up to address potentially out-of-date or inaccurate annotations. New evidence codes for high-throughput experiments now enable users to filter out annotations obtained from these sources. GO-CAM, a new framework for representing gene function that is more expressive than standard GO annotations, has been released, and users can now explore the growing repository of these models. We also provide the ‘GO ribbon’ widget for visualizing GO annotations to a gene; the widget can be easily embedded in any web page.
2,138 citations
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TL;DR: Male circumcision significantly reduces the risk of HIV acquisition in young men in Africa and should be integrated with other HIV preventive interventions and provided as expeditiously as possible.
1,692 citations
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TL;DR: The development of an algorithm for genome assembly, ALLPATHS-LG, and its application to massively parallel DNA sequence data from the human and mouse genomes, generated on the Illumina platform, have good accuracy, short-range contiguity, long-range connectivity, and coverage of the genome.
Abstract: Massively parallel DNA sequencing technologies are revolutionizing genomics by making it possible to generate billions of relatively short (~100-base) sequence reads at very low cost. Whereas such data can be readily used for a wide range of biomedical applications, it has proven difficult to use them to generate high-quality de novo genome assemblies of large, repeat-rich vertebrate genomes. To date, the genome assemblies generated from such data have fallen far short of those obtained with the older (but much more expensive) capillary-based sequencing approach. Here, we report the development of an algorithm for genome assembly, ALLPATHS-LG, and its application to massively parallel DNA sequence data from the human and mouse genomes, generated on the Illumina platform. The resulting draft genome assemblies have good accuracy, short-range contiguity, long-range connectivity, and coverage of the genome. In particular, the base accuracy is high (≥99.95%) and the scaffold sizes (N50 size = 11.5 Mb for human and 7.2 Mb for mouse) approach those obtained with capillary-based sequencing. The combination of improved sequencing technology and improved computational methods should now make it possible to increase dramatically the de novo sequencing of large genomes. The ALLPATHS-LG program is available at http://www.broadinstitute.org/science/programs/genome-biology/crd.
1,616 citations