piwi

Summary

Gene Symbol: piwi
Description: P-element induced wimpy testis
Alias: CG6122, Dmel\CG6122, PIWI, Piwi, P-element induced wimpy testis, CG6122-PA, CG6122-PB, piwi-PA, piwi-PB
Species: fruit fly

Top Publications

  1. Haase A, Fenoglio S, Muerdter F, Guzzardo P, Czech B, Pappin D, et al. Probing the initiation and effector phases of the somatic piRNA pathway in Drosophila. Genes Dev. 2010;24:2499-504 pubmed publisher
    Combining RNAi in cultured cells and analysis of mutant animals, we probed the roles of known Piwi-interacting RNA (piRNA) pathway components in the initiation and effector phases of transposon silencing...
  2. Anand A, Kai T. The tudor domain protein kumo is required to assemble the nuage and to generate germline piRNAs in Drosophila. EMBO J. 2012;31:870-82 pubmed publisher
    In Drosophila ovaries, distinct Piwi-interacting RNA (piRNA) pathways defend against transposons in somatic and germline cells. Germline piRNAs predominantly arise from bidirectional clusters and are amplified by the ping-pong cycle...
  3. Saito K, Nishida K, Mori T, Kawamura Y, Miyoshi K, Nagami T, et al. Specific association of Piwi with rasiRNAs derived from retrotransposon and heterochromatic regions in the Drosophila genome. Genes Dev. 2006;20:2214-22 pubmed
    In Drosophila, Piwi (P-element-induced wimpy testis), which encodes a protein of the Argonaute family, is essential for germ stem cell self-renewal...
  4. Obbard D, Gordon K, Buck A, Jiggins F. The evolution of RNAi as a defence against viruses and transposable elements. Philos Trans R Soc Lond B Biol Sci. 2009;364:99-115 pubmed publisher
    ..Over longer time scales, key RNAi genes are repeatedly duplicated or lost across the metazoan phylogeny, with important implications for RNAi as an immune defence. ..
  5. Huang X, Yin H, Sweeney S, Raha D, Snyder M, Lin H. A major epigenetic programming mechanism guided by piRNAs. Dev Cell. 2013;24:502-16 pubmed publisher
    ..Previously, we reported that a Piwi-piRNA complex associates with the piRNA-complementary site in the Drosophila genome and regulates its epigenetic ..
  6. Smulders Srinivasan T, Szakmary A, Lin H. A Drosophila chromatin factor interacts with the Piwi-interacting RNA mechanism in niche cells to regulate germline stem cell self-renewal. Genetics. 2010;186:573-83 pubmed publisher
    ..However, epigenetic programming of niche cells remains unexplored. We showed previously that Piwi plays a crucial role in Piwi-interacting RNA-mediated epigenetic regulation and functions in the niche cells to ..
  7. Chen D, McKearin D. Gene circuitry controlling a stem cell niche. Curr Biol. 2005;15:179-84 pubmed
    ..In Drosophila, germline stem cell (GSC) maintenance requires regulation of several genes, including dpp, piwi, pumilio, and bam...
  8. Schulz C, Wood C, Jones D, Tazuke S, Fuller M. Signaling from germ cells mediated by the rhomboid homolog stet organizes encapsulation by somatic support cells. Development. 2002;129:4523-34 pubmed
    ..The micro-environment provided by the surrounding somatic cells may, in turn, regulate differentiation of the germ cells they enclose. ..
  9. Klattenhoff C, Xi H, Li C, Lee S, Xu J, Khurana J, et al. The Drosophila HP1 homolog Rhino is required for transposon silencing and piRNA production by dual-strand clusters. Cell. 2009;138:1137-49 pubmed publisher
    b>Piwi-interacting RNAs (piRNAs) silence transposons and maintain genome integrity during germline development...

More Information

Publications83

  1. Nishimasu H, Ishizu H, Saito K, Fukuhara S, Kamatani M, Bonnefond L, et al. Structure and function of Zucchini endoribonuclease in piRNA biogenesis. Nature. 2012;491:284-7 pubmed publisher
    b>PIWI-interacting RNAs (piRNAs) silence transposons to maintain genome integrity in animal germ lines. piRNAs are classified as primary and secondary piRNAs, depending on their biogenesis machinery...
  2. Lin H. piRNAs in the germ line. Science. 2007;316:397 pubmed
    ..Recently, a class of small RNAs that interact with Piwi proteins has been discovered in the mammalian germ line and Drosophila...
  3. Szakmary A, Reedy M, Qi H, Lin H. The Yb protein defines a novel organelle and regulates male germline stem cell self-renewal in Drosophila melanogaster. J Cell Biol. 2009;185:613-27 pubmed publisher
    ..the proliferation of both germline and somatic stem cells in the Drosophila melanogaster ovary by activating piwi and hh expression in niche cells...
  4. Pal Bhadra M, Leibovitch B, Gandhi S, Chikka M, Rao M, Bhadra U, et al. Heterochromatic silencing and HP1 localization in Drosophila are dependent on the RNAi machinery. Science. 2004;303:669-72 pubmed
    ..mini-white arrays and white transgenes in heterochromatin to show loss of silencing as a result of mutations in piwi, aubergine, or spindle-E (homeless), which encode RNAi components...
  5. Rouget C, Papin C, Boureux A, Meunier A, Franco B, Robine N, et al. Maternal mRNA deadenylation and decay by the piRNA pathway in the early Drosophila embryo. Nature. 2010;467:1128-32 pubmed publisher
    b>Piwi-associated RNAs (piRNAs), a specific class of 24- to 30-nucleotide-long RNAs produced by the Piwi-type of Argonaute proteins, have a specific germline function in repressing transposable elements...
  6. Pal Bhadra M, Bhadra U, Birchler J. RNAi related mechanisms affect both transcriptional and posttranscriptional transgene silencing in Drosophila. Mol Cell. 2002;9:315-27 pubmed
    ..Mutations in piwi, which belongs to a gene family with members required for RNAi, block PTGS and one aspect of TGS, indicating a ..
  7. Nishida K, Saito K, Mori T, Kawamura Y, Nagami Okada T, Inagaki S, et al. Gene silencing mechanisms mediated by Aubergine piRNA complexes in Drosophila male gonad. RNA. 2007;13:1911-22 pubmed
    Genetic studies have shown that Aubergine (Aub), one of the Piwi subfamily of Argonautes in Drosophila, is essential for germ cell formation and maintaining fertility...
  8. Liu L, Qi H, Wang J, Lin H. PAPI, a novel TUDOR-domain protein, complexes with AGO3, ME31B and TRAL in the nuage to silence transposition. Development. 2011;138:1863-73 pubmed publisher
    ..Recently, the nuage in Drosophila was shown to contain two of the three PIWI proteins - Aubergine and Argonaute 3 (AGO3) - that are essential for germline development...
  9. Sienski G, Donertas D, Brennecke J. Transcriptional silencing of transposons by Piwi and maelstrom and its impact on chromatin state and gene expression. Cell. 2012;151:964-80 pubmed publisher
    ..Here, we show that the HMG protein Maelstrom is essential for Piwi-mediated silencing in Drosophila...
  10. Klenov M, Sokolova O, Yakushev E, Stolyarenko A, Mikhaleva E, Lavrov S, et al. Separation of stem cell maintenance and transposon silencing functions of Piwi protein. Proc Natl Acad Sci U S A. 2011;108:18760-5 pubmed publisher
    b>Piwi-interacting RNAs (piRNAs) and Piwi proteins have the evolutionarily conserved function of silencing of repetitive genetic elements in germ lines...
  11. Rozhkov N, Hammell M, Hannon G. Multiple roles for Piwi in silencing Drosophila transposons. Genes Dev. 2013;27:400-12 pubmed publisher
    Silencing of transposons in the Drosophila ovary relies on three Piwi family proteins--Piwi, Aubergine (Aub), and Ago3--acting in concert with their small RNA guides, the Piwi-interacting RNAs (piRNAs)...
  12. Klenov M, Lavrov S, Stolyarenko A, Ryazansky S, Aravin A, Tuschl T, et al. Repeat-associated siRNAs cause chromatin silencing of retrotransposons in the Drosophila melanogaster germline. Nucleic Acids Res. 2007;35:5430-8 pubmed
    ..melanogaster is mediated by repeat-associated short interfering RNAs (rasiRNAs) interacting with proteins of the Piwi subfamily...
  13. Harris A, Macdonald P. Aubergine encodes a Drosophila polar granule component required for pole cell formation and related to eIF2C. Development. 2001;128:2823-32 pubmed
    ..Unlike two other known polar granule components, Vasa and Oskar, Aubergine remains cytoplasmic after pole cell formation, suggesting that the roles of these proteins diverge during embryogenesis. ..
  14. Chotkowski H, Ciota A, Jia Y, Puig Basagoiti F, Kramer L, Shi P, et al. West Nile virus infection of Drosophila melanogaster induces a protective RNAi response. Virology. 2008;377:197-206 pubmed publisher
    ..melanogaster, and adult flies containing mutations in each of four different RNAi genes (Argonaute 2, spindle-E, piwi, and Dicer-2) were significantly more susceptible to WNV infection than wildtype flies...
  15. Arkov A, Ramos A. Building RNA-protein granules: insight from the germline. Trends Cell Biol. 2010;20:482-90 pubmed publisher
    ..of crucial RNA and protein components of the granules, including DEAD-box helicases, Tudor domain proteins, Piwi/Argonaute proteins and piRNA...
  16. Lin H, Spradling A. A novel group of pumilio mutations affects the asymmetric division of germline stem cells in the Drosophila ovary. Development. 1997;124:2463-76 pubmed
    ..We have also identified a second and novel gene, piwi, whose mutations abolish germline stem cell division.
  17. Shpiz S, Kwon D, Uneva A, Kim M, Klenov M, Rozovsky Y, et al. Characterization of Drosophila telomeric retroelement TAHRE: transcription, transpositions, and RNAi-based regulation of expression. Mol Biol Evol. 2007;24:2535-45 pubmed
    ..TAHRE transcripts in ovaries is strongly upregulated owing to mutations in the RNA interference genes spn-E, aub, piwi, and vasa locus. spn-E mutations eliminate TAHRE-specific short RNAs in the ovaries...
  18. Pelisson A, Sarot E, Payen Groschêne G, Bucheton A. A novel repeat-associated small interfering RNA-mediated silencing pathway downregulates complementary sense gypsy transcripts in somatic cells of the Drosophila ovary. J Virol. 2007;81:1951-60 pubmed
    ..The rasiRNA-associated protein Piwi (but not Aub) is required for gypsy silencing, whereas Dicer-2 (which makes siRNAs) is not...
  19. Cox D, Chao A, Baker J, Chang L, Qiao D, Lin H. A novel class of evolutionarily conserved genes defined by piwi are essential for stem cell self-renewal. Genes Dev. 1998;12:3715-27 pubmed
    ..We cloned and characterized the Drosophila piwi gene and showed that it is required for the asymmetric division of GSCs to produce and maintain a daughter GSC but ..
  20. Williams R, Rubin G. ARGONAUTE1 is required for efficient RNA interference in Drosophila embryos. Proc Natl Acad Sci U S A. 2002;99:6889-94 pubmed
    ..Furthermore, AGO1 is not required for siRNA production in vitro nor can the introduction of siRNA bypass AGO1 mutants in vivo. These data suggest that AGO1 functions downstream of siRNA production...
  21. Kavi H, Fernandez H, Xie W, Birchler J. RNA silencing in Drosophila. FEBS Lett. 2005;579:5940-9 pubmed
    ..RNA silencing processes in Drosophila are described. ..
  22. Lau N, Robine N, Martin R, Chung W, Niki Y, Berezikov E, et al. Abundant primary piRNAs, endo-siRNAs, and microRNAs in a Drosophila ovary cell line. Genome Res. 2009;19:1776-85 pubmed publisher
    b>Piwi proteins, a subclass of Argonaute-family proteins, carry approximately 24-30-nt Piwi-interacting RNAs (piRNAs) that mediate gonadal defense against transposable elements (TEs)...
  23. Lin H. The stem-cell niche theory: lessons from flies. Nat Rev Genet. 2002;3:931-40 pubmed
    ..These findings are illuminating our understanding of the self-renewing mechanisms of tissue stem cells in general. ..
  24. Kolaczkowski B, Hupalo D, Kern A. Recurrent adaptation in RNA interference genes across the Drosophila phylogeny. Mol Biol Evol. 2011;28:1033-42 pubmed publisher
    ..Our observations suggest a predictive model of how selective pressures generated by evolutionary arms race scenarios may affect multiple genes across protein interaction networks and other biochemical pathways. ..
  25. Malone C, Brennecke J, Dus M, Stark A, McCombie W, Sachidanandam R, et al. Specialized piRNA pathways act in germline and somatic tissues of the Drosophila ovary. Cell. 2009;137:522-35 pubmed publisher
    In Drosophila gonads, Piwi proteins and associated piRNAs collaborate with additional factors to form a small RNA-based immune system that silences mobile elements...
  26. Yin H, Lin H. An epigenetic activation role of Piwi and a Piwi-associated piRNA in Drosophila melanogaster. Nature. 2007;450:304-8 pubmed
    ..Implicated in heterochromatin formation and transcriptional silencing in Drosophila are Piwi (P-element induced wimpy testis) and repeat-associated small interfering RNAs (rasiRNAs)...
  27. Dufourt J, Brasset E, Desset S, Pouchin P, Vaury C. Polycomb group-dependent, heterochromatin protein 1-independent, chromatin structures silence retrotransposons in somatic tissues outside ovaries. DNA Res. 2011;18:451-61 pubmed publisher
    ..In Drosophila melanogaster, a silencing pathway implicating the argonaute protein PIWI represses retrotransposons in cells surrounding the oocyte, whereas a PIWI-independent pathway is involved in other ..
  28. Haynes K, Caudy A, Collins L, Elgin S. Element 1360 and RNAi components contribute to HP1-dependent silencing of a pericentric reporter. Curr Biol. 2006;16:2222-7 pubmed
    ..Silencing of the 1360, hsp70-white reporter is sensitive to mutations in RNAi components. Our results implicate 1360 as a target for sequence-specific heterochromatic silencing through an RNAi-dependent mechanism. ..
  29. Lei E, Corces V. RNA interference machinery influences the nuclear organization of a chromatin insulator. Nat Genet. 2006;38:936-41 pubmed
    ..These results suggest that the RNAi machinery acts as a modulator of nuclear architecture capable of effecting global changes in gene expression. ..
  30. Grimaud C, Bantignies F, Pal Bhadra M, Ghana P, Bhadra U, Cavalli G. RNAi components are required for nuclear clustering of Polycomb group response elements. Cell. 2006;124:957-71 pubmed
    ..Dicer-2, PIWI, and Argonaute1, three RNAi components, frequently colocalize with PcG bodies, and their mutation significantly ..
  31. Sarot E, Payen Groschêne G, Bucheton A, Pelisson A. Evidence for a piwi-dependent RNA silencing of the gypsy endogenous retrovirus by the Drosophila melanogaster flamenco gene. Genetics. 2004;166:1313-21 pubmed
    ..The piwi mutation, which is known to affect RNA-mediated homology-dependent transgene silencing, was also shown to impede ..
  32. Zhang Z, Xu J, Koppetsch B, Wang J, Tipping C, Ma S, et al. Heterotypic piRNA Ping-Pong requires qin, a protein with both E3 ligase and Tudor domains. Mol Cell. 2011;44:572-84 pubmed publisher
    piRNAs guide PIWI proteins to silence transposons in animal germ cells...
  33. Ni J, Zhou R, Czech B, Liu L, Holderbaum L, Yang Zhou D, et al. A genome-scale shRNA resource for transgenic RNAi in Drosophila. Nat Methods. 2011;8:405-7 pubmed publisher
    ..We show that shRNAs, modeled on an endogenous microRNA, are extremely effective at silencing gene expression during oogenesis. We also describe our progress toward building a genome-wide shRNA resource. ..
  34. Kirino Y, Kim N, De Planell Saguer M, Khandros E, Chiorean S, Klein P, et al. Arginine methylation of Piwi proteins catalysed by dPRMT5 is required for Ago3 and Aub stability. Nat Cell Biol. 2009;11:652-8 pubmed publisher
    b>Piwi family proteins are essential for germline development and bind piwi-interacting RNAs (piRNAs)...
  35. Pane A, Jiang P, Zhao D, Singh M, Schupbach T. The Cutoff protein regulates piRNA cluster expression and piRNA production in the Drosophila germline. EMBO J. 2011;30:4601-15 pubmed publisher
    In a broad range of organisms, Piwi-interacting RNAs (piRNAs) have emerged as core components of a surveillance system that protects the genome by silencing transposable and repetitive elements...
  36. Zamparini A, Davis M, Malone C, Vieira E, Zavadil J, Sachidanandam R, et al. Vreteno, a gonad-specific protein, is essential for germline development and primary piRNA biogenesis in Drosophila. Development. 2011;138:4039-50 pubmed publisher
    In Drosophila, Piwi proteins associate with Piwi-interacting RNAs (piRNAs) and protect the germline genome by silencing mobile genetic elements...
  37. King F, Szakmary A, Cox D, Lin H. Yb modulates the divisions of both germline and somatic stem cells through piwi- and hh-mediated mechanisms in the Drosophila ovary. Mol Cell. 2001;7:497-508 pubmed
    ..Here we show genetic interactions among fs(1)Yb (Yb), piwi, and hedgehog (hh) that regulate the division of both germline stem cells (GSCs) and somatic stem cells (SSCs), the ..
  38. Wang S, Elgin S. Drosophila Piwi functions downstream of piRNA production mediating a chromatin-based transposon silencing mechanism in female germ line. Proc Natl Acad Sci U S A. 2011;108:21164-9 pubmed publisher
    Transposon control is a critical process during reproduction. The PIWI family proteins can play a key role, using a piRNA-mediated slicing mechanism to suppress transposon activity posttranscriptionally...
  39. Vagin V, Sigova A, Li C, Seitz H, Gvozdev V, Zamore P. A distinct small RNA pathway silences selfish genetic elements in the germline. Science. 2006;313:320-4 pubmed
    ..Unlike siRNAs and miRNAs, rasiRNAs function through the Piwi, rather than the Ago, Argonaute protein subfamily...
  40. Brennecke J, Aravin A, Stark A, Dus M, Kellis M, Sachidanandam R, et al. Discrete small RNA-generating loci as master regulators of transposon activity in Drosophila. Cell. 2007;128:1089-103 pubmed
    Drosophila Piwi-family proteins have been implicated in transposon control...
  41. Grewal S, Elgin S. Transcription and RNA interference in the formation of heterochromatin. Nature. 2007;447:399-406 pubmed
    ..Silencing of chromatin might involve trans-acting sources of the crucial small RNAs that carry out RNA interference, but in some cases, transcription of the region to be silenced seems to be required--an apparent contradiction. ..
  42. Saito K, Inagaki S, Mituyama T, Kawamura Y, Ono Y, Sakota E, et al. A regulatory circuit for piwi by the large Maf gene traffic jam in Drosophila. Nature. 2009;461:1296-9 pubmed publisher
    b>PIWI-interacting RNAs (piRNAs) silence retrotransposons in Drosophila germ lines by associating with the PIWI proteins Argonaute 3 (AGO3), Aubergine (Aub) and Piwi...
  43. Zhang F, Wang J, Xu J, Zhang Z, Koppetsch B, Schultz N, et al. UAP56 couples piRNA clusters to the perinuclear transposon silencing machinery. Cell. 2012;151:871-884 pubmed publisher
    ..the DEAD box protein Vasa has an established role in piRNA production and localizes to nuage with the piRNA binding PIWI proteins Ago3 and Aub...
  44. Liu H, Wang J, Huang Y, Li Z, Gong W, Lehmann R, et al. Structural basis for methylarginine-dependent recognition of Aubergine by Tudor. Genes Dev. 2010;24:1876-81 pubmed publisher
    b>Piwi proteins are modified by symmetric dimethylation of arginine (sDMA), and the methylarginine-dependent interaction with Tudor domain proteins is critical for their functions in germline development...
  45. Moshkovich N, Nisha P, Boyle P, Thompson B, Dale R, Lei E. RNAi-independent role for Argonaute2 in CTCF/CP190 chromatin insulator function. Genes Dev. 2011;25:1686-701 pubmed publisher
    ..We propose that RNAi-independent recruitment of AGO2 to chromatin by insulator proteins promotes the definition of transcriptional domains throughout the genome. ..
  46. Zamore P. RNA silencing: genomic defence with a slice of pi. Nature. 2007;446:864-5 pubmed
  47. Qi H, Watanabe T, Ku H, Liu N, Zhong M, Lin H. The Yb body, a major site for Piwi-associated RNA biogenesis and a gateway for Piwi expression and transport to the nucleus in somatic cells. J Biol Chem. 2011;286:3789-97 pubmed publisher
    Despite exciting progress in understanding the Piwi-interacting RNA (piRNA) pathway in the germ line, less is known about this pathway in somatic cells...
  48. Shpiz S, Kwon D, Rozovsky Y, Kalmykova A. rasiRNA pathway controls antisense expression of Drosophila telomeric retrotransposons in the nucleus. Nucleic Acids Res. 2009;37:268-78 pubmed publisher
    ..Finally, this regulation occurs in the nucleus since disruption of the rasiRNA pathway leads to an accumulation of TART and HeT-A transcripts in germ cell nuclei. ..
  49. Hammond S, Boettcher S, Caudy A, Kobayashi R, Hannon G. Argonaute2, a link between genetic and biochemical analyses of RNAi. Science. 2001;293:1146-50 pubmed
    ..This observation begins the process of forging links between genetic analysis of RNAi from diverse organisms and the biochemical model of RNAi that is emerging from Drosophila in vitro systems. ..
  50. Perrini B, Piacentini L, Fanti L, Altieri F, Chichiarelli S, Berloco M, et al. HP1 controls telomere capping, telomere elongation, and telomere silencing by two different mechanisms in Drosophila. Mol Cell. 2004;15:467-76 pubmed
    ..Here, we tested this model, and we found that the capping function of HP1 is due to its direct binding to telomeric DNA, while the silencing of telomeric sequences and telomere elongation is due to its interaction with H3-MeK9. ..
  51. Shpiz S, Olovnikov I, Sergeeva A, Lavrov S, Abramov Y, Savitsky M, et al. Mechanism of the piRNA-mediated silencing of Drosophila telomeric retrotransposons. Nucleic Acids Res. 2011;39:8703-11 pubmed publisher
    In the Drosophila germline, retrotransposons are silenced by the PIWI-interacting RNA (piRNA) pathway...
  52. Simmons M, Ryzek D, Lamour C, Goodman J, Kummer N, Merriman P. Cytotype regulation by telomeric P elements in Drosophila melanogaster: evidence for involvement of an RNA interference gene. Genetics. 2007;176:1945-55 pubmed
    ..However, cytotype is not disrupted in stocks heterozygous for mutations in two other RNAi genes, piwi and homeless (spindle-E), or in a stock heterozygous for a mutation in the chromatin protein gene Enhancer of zeste...
  53. Saito K, Sakaguchi Y, Suzuki T, Suzuki T, Siomi H, Siomi M. Pimet, the Drosophila homolog of HEN1, mediates 2'-O-methylation of Piwi- interacting RNAs at their 3' ends. Genes Dev. 2007;21:1603-8 pubmed
    b>Piwi-interacting RNAs (piRNAs) consist of a germline-specific group of small RNAs derived from distinct intergenic loci in the genome...
  54. Nagao A, Mituyama T, Huang H, Chen D, Siomi M, Siomi H. Biogenesis pathways of piRNAs loaded onto AGO3 in the Drosophila testis. RNA. 2010;16:2503-15 pubmed publisher
    b>PIWI-interacting RNAs (piRNAs) silence transposable elements in animal germ cells...
  55. Murota Y, Ishizu H, Nakagawa S, Iwasaki Y, Shibata S, Kamatani M, et al. Yb integrates piRNA intermediates and processing factors into perinuclear bodies to enhance piRISC assembly. Cell Rep. 2014;8:103-13 pubmed publisher
    b>PIWI-interacting RNAs (piRNAs) direct Piwi to repress transposons and maintain genome integrity in Drosophila ovarian somatic cells...
  56. Cox D, Chao A, Lin H. piwi encodes a nucleoplasmic factor whose activity modulates the number and division rate of germline stem cells. Development. 2000;127:503-14 pubmed
    b>piwi represents the first class of genes known to be required for stem cell self-renewal in diverse organisms. In the Drosophila ovary, piwi is required in somatic signaling cells to maintain germline stem cells...
  57. Lu J, Clark A. Population dynamics of PIWI-interacting RNAs (piRNAs) and their targets in Drosophila. Genome Res. 2010;20:212-27 pubmed publisher
    ..Recently it was discovered that PIWI-interacting RNAs (piRNAs), a class of small RNA molecules that are mainly generated from transposable elements, are ..
  58. Olivieri D, Senti K, Subramanian S, Sachidanandam R, Brennecke J. The cochaperone shutdown defines a group of biogenesis factors essential for all piRNA populations in Drosophila. Mol Cell. 2012;47:954-69 pubmed publisher
    In animal gonads, PIWI proteins and their bound 23-30 nt piRNAs guard genome integrity by the sequence specific silencing of transposons...
  59. Josse T, Teysset L, Todeschini A, Sidor C, Anxolabehere D, Ronsseray S. Telomeric trans-silencing: an epigenetic repression combining RNA silencing and heterochromatin formation. PLoS Genet. 2007;3:1633-43 pubmed
    ..and the repeat-associated small interfering RNA (or rasiRNA) silencing pathway (aubergine, homeless, armitage, and piwi)...
  60. Castillo D, Mell J, Box K, Blumenstiel J. Molecular evolution under increasing transposable element burden in Drosophila: a speed limit on the evolutionary arms race. BMC Evol Biol. 2011;11:258 pubmed publisher
    ..Third, we test whether increasing TE abundance is correlated with greater codon bias in genes of the piRNA machinery. This is predicted if increasing TE abundance selects for increased efficiency in the machinery of genome defense...
  61. Gunawardane L, Saito K, Nishida K, Miyoshi K, Kawamura Y, Nagami T, et al. A slicer-mediated mechanism for repeat-associated siRNA 5' end formation in Drosophila. Science. 2007;315:1587-90 pubmed
    ..interfering RNAs (rasiRNAs) are produced in the germ line by a Dicer-independent pathway and function through the PIWI subfamily of Argonautes to ensure silencing of retrotransposons...
  62. Jin Z, Flynt A, Lai E. Drosophila piwi mutants exhibit germline stem cell tumors that are sustained by elevated Dpp signaling. Curr Biol. 2013;23:1442-8 pubmed publisher
    Drosophila Piwi is the founding member of a gonadal clade of Argonaute proteins that serve as silencing effectors for ?26-32 nt Piwi-interacting RNAs (piRNAs) [1], and piwi mutants exhibit dramatically rudimentary ovaries [2]...
  63. Kawamura Y, Saito K, Kin T, Ono Y, Asai K, Sunohara T, et al. Drosophila endogenous small RNAs bind to Argonaute 2 in somatic cells. Nature. 2008;453:793-7 pubmed publisher
    ..In the Drosophila germ line, Piwi-interacting RNAs arise from repetitive intergenic elements including retrotransposons by a Dicer-independent ..
  64. Moshkovich N, Lei E. HP1 recruitment in the absence of argonaute proteins in Drosophila. PLoS Genet. 2010;6:e1000880 pubmed publisher
    ..have suggested the involvement of both the AGO2-dependent endogenous small interfering RNA (endo-siRNA) as well as Piwi-interacting RNA (piRNA) silencing pathways...
  65. Li C, Vagin V, Lee S, Xu J, Ma S, Xi H, et al. Collapse of germline piRNAs in the absence of Argonaute3 reveals somatic piRNAs in flies. Cell. 2009;137:509-21 pubmed publisher
    b>Piwi-interacting RNAs (piRNAs) silence transposons in animal germ cells...
  66. Gangaraju V, Yin H, Weiner M, Wang J, Huang X, Lin H. Drosophila Piwi functions in Hsp90-mediated suppression of phenotypic variation. Nat Genet. 2011;43:153-8 pubmed publisher
    ..Drosophila eye-outgrowth assay sensitized by the dominant Kr(irregular facets-1)(Kr(If-1)) allele, we show that the Piwi-interacting RNA (piRNA) pathway, but not the short interfering RNA or micro RNA pathway, is involved in ..
  67. Olivieri D, Sykora M, Sachidanandam R, Mechtler K, Brennecke J. An in vivo RNAi assay identifies major genetic and cellular requirements for primary piRNA biogenesis in Drosophila. EMBO J. 2010;29:3301-17 pubmed publisher
    In Drosophila, PIWI proteins and bound PIWI-interacting RNAs (piRNAs) form the core of a small RNA-mediated defense system against selfish genetic elements...
  68. Desset S, Buchon N, Meignin C, Coiffet M, Vaury C. In Drosophila melanogaster the COM locus directs the somatic silencing of two retrotransposons through both Piwi-dependent and -independent pathways. PLoS ONE. 2008;3:e1526 pubmed publisher
    ..small RNAs of 26-30 nucleotides that are mainly produced from the antisense strand and function through the Piwi protein...
  69. Saito K, Ishizu H, Komai M, Kotani H, Kawamura Y, Nishida K, et al. Roles for the Yb body components Armitage and Yb in primary piRNA biogenesis in Drosophila. Genes Dev. 2010;24:2493-8 pubmed publisher
    b>PIWI-interacting RNAs (piRNAs) protect genome integrity from transposons. In Drosophila ovarian somas, primary piRNAs are produced and loaded onto Piwi...
  70. Donertas D, Sienski G, Brennecke J. Drosophila Gtsf1 is an essential component of the Piwi-mediated transcriptional silencing complex. Genes Dev. 2013;27:1693-705 pubmed publisher
    The PIWI-interacting RNA (piRNA) pathway is a small RNA silencing system that keeps selfish genetic elements such as transposons under control in animal gonads...
  71. Peng J, Karpen G. H3K9 methylation and RNA interference regulate nucleolar organization and repeated DNA stability. Nat Cell Biol. 2007;9:25-35 pubmed
    ..These results suggest a mechanism for how local chromatin structure can regulate genome stability, and the organization of chromosomal elements and nuclear organelles. ..
  72. Kavi H, Fernandez H, Xie W, Birchler J. Polycomb, pairing and PIWI--RNA silencing and nuclear interactions. Trends Biochem Sci. 2006;31:485-7 pubmed
    ..These Pc-associated sequences are involved with the control of the proper expression of developmental HOX genes. ..
  73. Preall J, Czech B, Guzzardo P, Muerdter F, Hannon G. shutdown is a component of the Drosophila piRNA biogenesis machinery. RNA. 2012;18:1446-57 pubmed publisher
    ..Shu contains domains implicated in peptidyl-prolyl cis-trans isomerase activity and in the binding of HSP90-family chaperones, though the relevance of these domains to piRNA biogenesis is unknown. ..
  74. Tritto P, Specchia V, Fanti L, Berloco M, D Alessandro R, Pimpinelli S, et al. Structure, regulation and evolution of the crystal-Stellate system of Drosophila. Genetica. 2003;117:247-57 pubmed
    ..They are requested during oogenesis and early in embryogenesis as well. Hypothesis on the involvement of these genes in activating the Stellate sequences are discussed. ..