Small RNAs in transcriptional gene silencing and genome defence
NaturePublished 1 January 2009
Danesh Moazed
Citations828
SJR quartileQ1
SJR score18.29
SNIP10.16
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TL;DR
Interactions between small RNAs and nascent non-coding transcripts reveal a new mechanism for targeting chromatin-modifying complexes to specific chromosome regions and suggest possibilities for how the resultant chromatin states may be inherited during the process of chromosome duplication.
Abstract
Small RNA molecules of about 20-30 nucleotides have emerged as powerful regulators of gene expression and genome stability. Studies in fission yeast and multicellular organisms suggest that effector complexes, directed by small RNAs, target nascent chromatin-bound non-coding RNAs and recruit chromatin-modifying complexes. Interactions between small RNAs and nascent non-coding transcripts thus reveal a new mechanism for targeting chromatin-modifying complexes to specific chromosome regions and suggest possibilities for how the resultant chromatin states may be inherited during the process of chromosome duplication.
Keywords
Agricultural and Biological SciencesBiochemistry, Genetics and Molecular Biology
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Nature Structural & Molecular BiologyTRAMP-mediated RNA surveillance prevents spurious entry of RNAs into the Schizosaccharomyces pombe siRNA pathway
192 Citations2008Marc Bühler, Noah Spies +2 more
High-throughput sequencing is used to analyze Argonaute-associated small RNAs (sRNAs) in both the presence and absence of Cid14, which prevents certain abundant RNAs from becoming substrates for theRNAi machinery, thereby freeing the RNAi machinery to act on its proper targets.
RNA BiologyA Cullin E3 Ubiquitin Ligase Complex Associates with Rik1 and the Clr4 Histone H3-K9 Methyltransferase and is Required for RNAi-Mediated Heterochromatin Formation
182 Citations2005Eun-Jin Erica Hong, Judit Villén +1 more
It is proposed that RNAi-mediated heterochromatin formation involves therecruitment of Clr4-Rik1-Cul4 complex through the putative nucleic acid binding domain of Rik1, which is associated with the fissionyeast E3 ubiquitin ligase Cullin4.
Genes & DevelopmentTranscriptional silencing of a transgene by RNAi in the soma of <i>C. elegans</i>
177 Citations2005Alla Grishok, Jina L. Sinskey +1 more
This type of silencing can be distinguished from transgene silencing in the soma by its inability to be transmitted across generations and its dependence on the rde-1 gene, and is defined as RNAi-induced Transcriptional Gene Silencing (RNAi-TGS).
PLoS BiologyTwo-Step Recruitment of RNA-Directed DNA Methylation to Tandem Repeats
175 Citations2006Wan Chan, Xiaoyu Zhang +2 more
It is shown that the FWA tandem repeats are necessary and sufficient for de novo DNA methylation and that repeated character rather than intrinsic sequence is likely important, suggesting that repeat acquisition may be a general mechanism for the evolution of gene silencing.
Molecular CellCoupling of Double-Stranded RNA Synthesis and siRNA Generation in Fission Yeast RNAi
161 Citations2007Serafin U. Colmenares, Shane M. Buker +3 more
It is shown that Dcr1, the fission yeast Dicer, is physically associated with RDRC, and this coupling has implications for cis-restriction of siRNA-mediated heterochromatin assembly and for mechanisms that give rise to siRNA strand polarity.
Genes & DevelopmentChromatin and RNAi factors protect the <i>C. elegans</i> germline against repetitive sequences
142 Citations2005Valérie Robert, Titia Sijen +2 more
Current BiologyA Member of the Polymerase β Nucleotidyltransferase Superfamily Is Required for RNA Interference in C. elegans
137 Citations2005Chun-Chieh G. Chen, Martin J. Simard +4 more
Genetic analysis of presumptive null alleles indicates that rde-3 is required for siRNA accumulation and for efficient RNAi in all tissues, and it is essential for fertility and viability at high temperatures, and suggest possible models for the role of RDE-3 in the RNAi mechanism.
Cell CycleMechanistic principles of chromatin remodeling guided by siRNAs and miRNAs
134 Citations2008Susana González, David G. Pisano +1 more
It is shown that miRNAs miR17-5p and miR20a from the oncomiR cluster miR-17-92 can induce heterochromatic features in promoters that undergo overlapping transcription and possess sequence complementarity to the miRNA seed region, unveiling a new level of gene regulation by miRNas.
ScienceSplicing Factors Facilitate RNAi-Directed Silencing in Fission Yeast
129 Citations2008Elizabeth H. Bayne, Manuela Portoso +7 more
It is proposed that spliceosomal complexes provide a platform for siRNA generation and hence facilitate effective centromere repeat silencing and consequently centromeric heterochromatin integrity.
Nature Structural & Molecular BiologyTwo different Argonaute complexes are required for siRNA generation and heterochromatin assembly in fission yeast
126 Citations2007Shane M. Buker, Tetsushi Iida +5 more
It is shown that slicer activity is required for the siRNA-dependent association of Ago1 with chromatin and for the spreading of histone H3-K9 methylation.
Genes & Development<i>Drosophila argonaute-2</i> is required early in embryogenesis for the assembly of centric/centromeric heterochromatin, nuclear division, nuclear migration, and germ-cell formation
124 Citations2005Girish Deshpande, Gretchen Calhoun +1 more
It is shown that Argonaute-2 (ago-2) is required for proper nuclear migration, pole cell formation, and cellularization during the early stages of embryonic development in Drosophila and points to a failure in the assembly of functional centromeres.
Molecular CellsiRNA-Mediated Heterochromatin Establishment Requires HP1 and Is Associated with Antisense Transcription
104 Citations2008Tetsushi Iida, Jun‐ichi Nakayama +1 more
It is shown that ectopic expression of a long hairpin RNA bypasses the requirement for chromatin-dependent steps in si RNA generation and provides insights into the regulation of siRNA action and reveals roles for cis-dsRNA synthesis and HP1 in siRNA-mediated heterochromatin assembly.
Nature Structural & Molecular BiologyPhysical and functional coupling of RNA-dependent RNA polymerase and Dicer in the biogenesis of endogenous siRNAs
92 Citations2007Suzanne R. Lee, Kathleen Collins
These findings suggest that sRNA strand bias arises from Dcr2 processing polarity, conferred by physical and functional coupling of RDRC and Dicer enzymes.
Current BiologyElement 1360 and RNAi Components Contribute to HP1-Dependent Silencing of a Pericentric Reporter
76 Citations2006Karmella A. Haynes, Amy A. Caudy +2 more
Molecular Genetics and Genomicsaubergine mutations in Drosophila melanogaster impair P cytotype determination by telomeric P elements inserted in heterochromatin.
58 Citations2004Daphné Reiss, Thibaut Josse +2 more
It is strongly suggested that both RNA interference and heterochromatin structure are involved in the establishment of the P cytotype elicited by telomeric P elements, and reinforce the hypothesis that different mechanisms for repression of P elements exist which depend on the chromosomal location of the regulatory copies of P.
Molecular and Cellular BiologyChp1-Tas3 Interaction Is Required To Recruit RITS to Fission Yeast Centromeres and for Maintenance of Centromeric Heterochromatin
48 Citations2008Jennifer DeBeauchamp, Arian Moses +5 more
A pivotal role is suggested for Chp1 and its association with Tas3 for the recruitment of RITS, RDRC, and histone H3 K9 methyltransferase activity to centromeres in fission yeast.
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