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Small RNAs in transcriptional gene silencing and genome defence

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.

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Figure 1: Pathways of RNA processing and biogenesis of small RNAs.
Figure 2: Chromosome organization and the nascent transcript model for heterochromatic gene-silencing assembly in Schizosaccharomyces pombe.
Figure 3: Argonaute complexes that link RNA silencing to chromatin modifications.

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Acknowledgements

I thank the members of my laboratory and colleagues in the chromatin and RNA silencing fields for fruitful discussions, and the National Institutes of Health, the Leukemia and Lymphoma Society, and the Howard Hughes Medical Institute for funding.

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Moazed, D. Small RNAs in transcriptional gene silencing and genome defence. Nature 457, 413–420 (2009). https://doi.org/10.1038/nature07756

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