Heterotypic piRNA Ping-Pong requires qin, a protein with both E3 ligase and Tudor domains
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UMass Chan Affiliations
Program in Molecular MedicineProgram in Bioinformatics and Integrative Biology
Department of Biochemistry and Molecular Pharmacology
Document Type
ArticlePublication Date
2011-11-18Keywords
AnimalsArgonaute Proteins
Cell Nucleus
Computational Biology
DNA Damage
DNA Transposable Elements
Drosophila Proteins
Drosophila melanogaster
Female
Fertility*Gene Silencing*Genome, InsectMembrane Transport ProteinsMutationOocytesOvaryPeptide Initiation FactorsProtein Structure, TertiaryRNA CleavageRNA, Small InterferingRNA-Induced Silencing ComplexSignal TransductionUbiquitin-Protein LigasesUMCCTS fundingBiochemistry, Biophysics, and Structural Biology
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piRNAs guide PIWI proteins to silence transposons in animal germ cells. Reciprocal cycles of piRNA-directed RNA cleavage--catalyzed by the PIWI proteins Aubergine (Aub) and Argonaute3 (Ago3) in Drosophila melanogaster--expand the population of antisense piRNAs in response to transposon expression, a process called the Ping-Pong cycle. Heterotypic Ping-Pong between Aub and Ago3 ensures that antisense piRNAs predominate. We show that qin, a piRNA pathway gene whose protein product contains both E3 ligase and Tudor domains, colocalizes with Aub and Ago3 in nuage, a perinuclear structure implicated in transposon silencing. In qin mutants, less Ago3 binds Aub, futile Aub:Aub homotypic Ping-Pong prevails, antisense piRNAs decrease, many families of mobile genetic elements are reactivated, and DNA damage accumulates in nurse cells and oocytes. We propose that Qin enforces heterotypic Ping-Pong between Aub and Ago3, ensuring that transposons are silenced and maintaining the integrity of the germline genome.Source
Mol Cell. 2011 Nov 18;44(4):572-84. doi: 10.1016/j.molcel.2011.10.011. Link to article on publisher's site
DOI
10.1016/j.molcel.2011.10.011Permanent Link to this Item
http://hdl.handle.net/20.500.14038/26025PubMed ID
22099305Notes
Author Zhao Zhang is a student in the Interdisciplinary Graduate Program in the Graduate School of Biomedical Sciences (GSBS) at UMass Medical School.
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