RRC ID 73753
Author Gunawardane LS, Saito K, Nishida KM, Miyoshi K, Kawamura Y, Nagami T, Siomi H, Siomi MC.
Title A slicer-mediated mechanism for repeat-associated siRNA 5' end formation in Drosophila.
Journal Science
Abstract In Drosophila, repeat-associated small 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. We sequenced small RNAs associated with the PIWI subfamily member AGO3. Although other members of PIWI, Aubergine (Aub) and Piwi, associated with rasiRNAs derived mainly from the antisense strand of retrotransposons, AGO3-associated rasiRNAs arose mainly from the sense strand. Aub- and Piwi-associated rasiRNAs showed a strong preference for uracil at their 5' ends, and AGO3-associated rasiRNAs showed a strong preference for adenine at nucleotide 10. Comparisons between AGO3- and Aub-associated rasiRNAs revealed pairs of rasiRNAs showing complementarities in their first 10 nucleotides. Aub and AGO3 exhibited Slicer activity in vitro. These data support a model in which formation of a 5' terminus within rasiRNA precursors is guided by rasiRNAs originating from transcripts of the other strand in concert with the Slicer activity of PIWI.
Volume 315(5818)
Pages 1587-90
Published 2007-3-16
DOI 10.1126/science.1140494
PII 1140494
PMID 17322028
MeSH Amino Acid Sequence Animals Argonaute Proteins Drosophila Proteins / chemistry Drosophila Proteins / genetics Drosophila Proteins / metabolism* Drosophila melanogaster / embryology Drosophila melanogaster / genetics* Drosophila melanogaster / metabolism Female Gene Library Male Models, Genetic Molecular Sequence Data Ovary / metabolism Peptide Initiation Factors / chemistry Peptide Initiation Factors / genetics Peptide Initiation Factors / metabolism* Proteins / genetics Proteins / metabolism RNA Interference RNA, Small Interfering / chemistry RNA, Small Interfering / genetics RNA, Small Interfering / metabolism* RNA-Induced Silencing Complex Recombinant Fusion Proteins / metabolism Retroelements Testis / metabolism
IF 41.846
Drosophila 10002Ab-1