Arkhipova Irina R.

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Arkhipova
First Name
Irina R.
ORCID
0000-0002-4805-1339

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  • Article
    Genomic impact of eukaryotic transposable elements
    (BioMed Central, 2012-11-21) Arkhipova, Irina R. ; Batzer, Mark A. ; Brosius, Juergen ; Feschotte, Cedric ; Moran, John V. ; Schmitz, Jurgen ; Jurka, Jerzy
    The third international conference on the genomic impact of eukaryotic transposable elements (TEs) was held 24 to 28 February 2012 at the Asilomar Conference Center, Pacific Grove, CA, USA. Sponsored in part by the National Institutes of Health grant 5 P41 LM006252, the goal of the conference was to bring together researchers from around the world who study the impact and mechanisms of TEs using multiple computational and experimental approaches. The meeting drew close to 170 attendees and included invited floor presentations on the biology of TEs and their genomic impact, as well as numerous talks contributed by young scientists. The workshop talks were devoted to computational analysis of TEs with additional time for discussion of unresolved issues. Also, there was ample opportunity for poster presentations and informal evening discussions. The success of the meeting reflects the important role of Repbase in comparative genomic studies, and emphasizes the need for close interactions between experimental and computational biologists in the years to come.
  • Article
    Distribution and phylogeny of Penelope-like elements in eukaryotes
    (Oxford University Press, 2006-10) Arkhipova, Irina R.
    Penelope-like elements (PLEs) are a relatively little studied class of eukaryotic retroelements, distinguished by the presence of the GIY-YIG endonuclease domain, the ability of some representatives to retain introns, and the similarity of PLE-encoded reverse transcriptases to telomerases. Although these retrotransposons are abundant in many animal genomes, the reverse transcriptase moiety can also be found in several protists, fungi, and plants, indicating its ancient origin. A comprehensive phylogenetic analysis of PLEs was conducted, based on extended sequence alignments and a considerably expanded data set. PLEs exhibit the pattern of evolution similar to that of non-LTR retrotransposons, which form deep-branching clades dating back to the Precambrian era. However, PLEs seem to have experienced a much higher degree of lineage losses than non-LTR retrotransposons. It is suggested that PLEs and non-LTR retrotransposons are included into a larger eTPRT (eukaryotic target-primed) group of retroelements, characterized by 5' truncation, variable target-site duplication, and the potential of the 3' end to participate in formation of non-autonomous derivatives.
  • Article
    Meeting report : mobile genetic elements and genome plasticity 2018
    (BMC, 2018-06-22) Abrams, John M. ; Arkhipova, Irina R. ; Belfort, Marlene ; Boeke, Jef D. ; Curcio, M. Joan ; Faulkner, Geoffrey J. ; Goodier, John L. ; Lehmann, Ruth ; Levin, Henry L.
    The Mobile Genetic Elements and Genome Plasticity conference was hosted by Keystone Symposia in Santa Fe, NM USA, February 11–15, 2018. The organizers were Marlene Belfort, Evan Eichler, Henry Levin and Lynn Maquat. The goal of this conference was to bring together scientists from around the world to discuss the function of transposable elements and their impact on host species. Central themes of the meeting included recent innovations in genome analysis and the role of mobile DNA in disease and evolution. The conference included 200 scientists who participated in poster presentations, short talks selected from abstracts, and invited talks. A total of 58 talks were organized into eight sessions and two workshops. The topics varied from mechanisms of mobilization, to the structure of genomes and their defense strategies to protect against transposable elements.
  • Article
    Using bioinformatic and phylogenetic approaches to classify transposable elements and understand their complex evolutionary histories
    (BioMed Central, 2017-12-06) Arkhipova, Irina R.
    In recent years, much attention has been paid to comparative genomic studies of transposable elements (TEs) and the ensuing problems of their identification, classification, and annotation. Different approaches and diverse automated pipelines are being used to catalogue and categorize mobile genetic elements in the ever-increasing number of prokaryotic and eukaryotic genomes, with little or no connectivity between different domains of life. Here, an overview of the current picture of TE classification and evolutionary relationships is presented, updating the diversity of TE types uncovered in sequenced genomes. A tripartite TE classification scheme is proposed to account for their replicative, integrative, and structural components, and the need to expand in vitro and in vivo studies of their structural and biological properties is emphasized. Bioinformatic studies have now become front and center of novel TE discovery, and experimental pursuits of these discoveries hold great promise for both basic and applied science.
  • Article
    LTR-retrotransposons from Bdelloid rotifers capture additional ORFs shared between highly diverse retroelement types
    (MDPI AG, 2017-04-11) Rodriguez, Fernando ; Kenefick, Aubrey W. ; Arkhipova, Irina R.
    Rotifers of the class Bdelloidea, microscopic freshwater invertebrates, possess a highlydiversified repertoire of transposon families, which, however, occupy less than 4% of genomic DNA in the sequenced representative Adineta vaga. We performed a comprehensive analysis of A. vaga retroelements, and found that bdelloid long terminal repeat (LTR)retrotransposons, in addition to conserved open reading frame (ORF) 1 and ORF2 corresponding to gag and pol genes, code for an unusually high variety of ORF3 sequences. Retrovirus-like LTR families in A. vaga belong to four major lineages, three of which are rotiferspecific and encode a dUTPase domain. However only one lineage contains a canonical envlike fusion glycoprotein acquired from paramyxoviruses (non-segmented negative-strand RNA viruses), although smaller ORFs with transmembrane domains may perform similar roles. A different ORF3 type encodes a GDSL esterase/lipase, which was previously identified as ORF1 in several clades of non-LTR retrotransposons, and implicated in membrane targeting. Yet another ORF3 type appears in unrelated LTR-retrotransposon lineages, and displays strong homology to DEDDy-type exonucleases involved in 3′-end processing of RNA and single-stranded DNA. Unexpectedly, each of the enzymatic ORF3s is also associated with different subsets of Penelope-like Athena retroelement families. The unusual association of the same ORF types with retroelements from different classes reflects their modular structure with a high degree of flexibility, and points to gene sharing between different groups of retroelements.
  • Article
    Functional organization of hsp70 cluster in camel (Camelus dromedarius) and other mammals
    (Public Library of Science, 2011-11-09) Garbuz, David G. ; Astakhova, Lubov N. ; Zatsepina, Olga G. ; Arkhipova, Irina R. ; Nudler, Eugene ; Evgenev, Michael B.
    Heat shock protein 70 (Hsp70) is a molecular chaperone providing tolerance to heat and other challenges at the cellular and organismal levels. We sequenced a genomic cluster containing three hsp70 family genes linked with major histocompatibility complex (MHC) class III region from an extremely heat tolerant animal, camel (Camelus dromedarius). Two hsp70 family genes comprising the cluster contain heat shock elements (HSEs), while the third gene lacks HSEs and should not be induced by heat shock. Comparison of the camel hsp70 cluster with the corresponding regions from several mammalian species revealed similar organization of genes forming the cluster. Specifically, the two heat inducible hsp70 genes are arranged in tandem, while the third constitutively expressed hsp70 family member is present in inverted orientation. Comparison of regulatory regions of hsp70 genes from camel and other mammals demonstrates that transcription factor matches with highest significance are located in the highly conserved 250-bp upstream region and correspond to HSEs followed by NF-Y and Sp1 binding sites. The high degree of sequence conservation leaves little room for putative camel-specific regulatory elements. Surprisingly, RT-PCR and 5′/3′-RACE analysis demonstrated that all three hsp70 genes are expressed in camel's muscle and blood cells not only after heat shock, but under normal physiological conditions as well, and may account for tolerance of camel cells to extreme environmental conditions. A high degree of evolutionary conservation observed for the hsp70 cluster always linked with MHC locus in mammals suggests an important role of such organization for coordinated functioning of these vital genes.
  • Article
    Endonuclease-containing Penelope retrotransposons in the bdelloid rotifer Adineta vaga exhibit unusual structural features and play a role in expansion of host gene families
    (BioMed Central, 2013-08-27) Arkhipova, Irina R. ; Yushenova, Irina A. ; Rodriguez, Fernando
    Penelope-like elements (PLEs) are an enigmatic group of retroelements sharing a common ancestor with telomerase reverse transcriptases. In our previous studies, we identified endonuclease-deficient PLEs that are associated with telomeres in bdelloid rotifers, small freshwater invertebrates best known for their long-term asexuality and high foreign DNA content. Completion of the high-quality draft genome sequence of the bdelloid rotifer Adineta vaga provides us with the opportunity to examine its genomic transposable element (TE) content, as well as TE impact on genome function and evolution. We performed an exhaustive search of the A. vaga genome assembly, aimed at identification of canonical PLEs combining both the reverse transcriptase (RT) and the GIY-YIG endonuclease (EN) domains. We find that the RT/EN-containing Penelope families co-exist in the A. vaga genome with the EN-deficient RT-containing Athena retroelements. Canonical PLEs are present at very low copy numbers, often as a single-copy, and there is no evidence that they might preferentially co-mobilize EN-deficient PLEs. We also find that Penelope elements can participate in expansion of A. vaga multigene families via trans-action of their enzymatic machinery, as evidenced by identification of intron-containing host genes framed by the Penelope terminal repeats and characteristic target-site duplications generated upon insertion. In addition, we find that Penelope open reading frames (ORFs) in several families have incorporated long stretches of coding sequence several hundred amino acids (aa) in length that are highly enriched in asparagine residues, a phenomenon not observed in other retrotransposons. Our results show that, despite their low abundance and low transcriptional activity in the A. vaga genome, endonuclease-containing Penelope elements can participate in expansion of host multigene families. We conclude that the terminal repeats represent the cis-acting sequences required for mobilization of the intervening region in trans by the Penelope-encoded enzymatic activities. We also hypothesize that the unusual capture of long N-rich segments by the Penelope ORF occurs as a consequence of peculiarities of its replication mechanism. These findings emphasize the unconventional nature of Penelope retrotransposons, which, in contrast to all other retrotransposon types, are capable of dispersing intron-containing genes, thereby questioning the validity of traditional estimates of gene retrocopies in PLE-containing eukaryotic genomes.
  • Article
    Genomic evidence for ameiotic evolution in the bdelloid rotifer Adineta vaga
    (Nature Publishing Group, 2013-07-21) Flot, Jean-Francois ; Hespeels, Boris ; Li, Xiang ; Noel, Benjamin ; Arkhipova, Irina R. ; Danchin, Etienne G. J. ; Hejno, Andreas ; Henrissat, Bernard ; Koszul, Romain ; Aury, Jean-Marc ; Barbe, Valerie ; Barthelemy, Roxane-Marie ; Bast, Jens ; Bazykin, Georgii A. ; Chabrol, Olivier ; Couloux, Arnaud ; Da Rocha, Martine ; Da Silva, Corinne ; Gladyshev, Eugene A. ; Gouret, Philippe ; Hallatschek, Oskar ; Hecox-Lea, Bette ; Labadie, Karine ; Lejeune, Benjamin ; Piskurek, Oliver ; Poulain, Julie ; Rodriguez, Fernando ; Ryan, Joseph F. ; Vakhrusheva, Olga A. ; Wajnberg, Eric ; Wirth, Benedicte ; Yushenova, Irina A. ; Kellis, Manolis ; Kondrashov, Alexey S. ; Mark Welch, David B. ; Pontarotti, Pierre ; Weissenbach, Jean ; Wincker, Patrick ; Jaillon, Olivier ; Van Doninck, Karine
    Loss of sexual reproduction is considered an evolutionary dead end for metazoans, but bdelloid rotifers challenge this view as they appear to have persisted asexually for millions of years1. Neither male sex organs nor meiosis have ever been observed in these microscopic animals: oocytes are formed through mitotic divisions, with no reduction of chromosome number and no indication of chromosome pairing2. However, current evidence does not exclude that they may engage in sex on rare, cryptic occasions. Here we report the genome of a bdelloid rotifer, Adineta vaga (Davis, 1873)3, and show that its structure is incompatible with conventional meiosis. At gene scale, the genome of A. vaga is tetraploid and comprises both anciently duplicated segments and less divergent allelic regions. However, in contrast to sexual species, the allelic regions are rearranged and sometimes even found on the same chromosome. Such structure does not allow meiotic pairing; instead, we find abundant evidence of gene conversion, which may limit the accumulation of deleterious mutations in the absence of meiosis. Gene families involved in resistance to oxidation, carbohydrate metabolism and defence against transposons are significantly expanded, which may explain why transposable elements cover only 3% of the assembled sequence. Furthermore, 8% of the genes are likely to be of non-metazoan origin and were probably acquired horizontally. This apparent convergence between bdelloids and prokaryotes sheds new light on the evolutionary significance of sex.
  • Article
    Molecular dissection of Penelope transposable element regulatory machinery
    (Oxford University Press, 2008-03-04) Schostak, Nataliya ; Pyatkov, Konstantin ; Zelentsova, Elena ; Arkhipova, Irina R. ; Shagin, Dmitrii ; Shagina, Irina ; Mudrik, Elena ; Blintsov, Anatolii ; Clark, Ivan ; Finnegan, David J. ; Evgenev, Michael B.
    Penelope-like elements (PLEs) represent a new class of retroelements identified in more than 80 species belonging to at least 10 animal phyla. Penelope isolated from Drosophila virilis is the only known transpositionally active representative of this class. Although the size and structure of the Penelope major transcript has been previously described in both D. virilis and D. melanogaster transgenic strains, the architecture of the Penelope regulatory region remains unknown. In order to determine the localization of presumptive Penelope promoter and enhancer-like elements, segments of the putative Penelope regulatory region were linked to a CAT reporter gene and introduced into D. melanogaster by P-element-mediated transformation. The results obtained using ELISA to measure CAT expression levels and RNA studies, including RT–PCR, suggest that the active Penelope transposon contains an internal promoter similar to the TATA-less promoters of LINEs. The results also suggest that some of the Penelope regulatory sequences control the preferential expression in the ovaries of the adult flies by enhancing expression in the ovary and reducing expression in the carcass. The possible significance of the intron within Penelope for the function and evolution of PLEs, and the effect of Penelope insertions on adjacent genes, are discussed.
  • Article
    The common morphospecies Cypridopsis vidua (O.F. MÜLLER, 1776) (Crustacea, Ostracoda) is not an obligate parthenogen
    (Royal Belgian Zoology Society, 2023-01-19) Martens, Koen ; Shribak, Michael ; Arkhipova, Irina ; Schön, Isa
    The common non-marine ostracod Cypridopsis vidua (O.F. Müller, 1776) is used as a proxy in various biological disciplines, such as (palaeo-)ecology, evolutionary biology, ecotoxicology and parasitology. This morphospecies was considered to be an obligate parthenogen. We report on the discovery of the first population of C. vidua with males from Woods Hole (MA, USA) and determine that it is a population with mixed reproduction. We describe the morphology of the males and of the sexual and asexual females. We illustrate a copula of a male and a sexual female as well insemination in a sexual female, showing that males are functional. Therefore, Cypridopsis vidua is a morphospecies with mixed reproduction, not a full apomictic parthenogen. We use, for the first time, polychromatic polarization microscope technology to illustrate soft parts of ostracods. In addition, we compare the sexual species C. bisexualis, C. okeechobei, C. howei and C. schwartzi and conclude that these species, especially the latter three, are morphologically very close to C. vidua.