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The role of RNA interference in heterochromatic silencing

Abstract

Soon after its discovery 75 years ago, heterochromatin, a dense chromosomal material, was found to silence genes. But its importance in regulating gene expression was controversial. Long thought to be inert, heterochromatin is now known to give rise to small RNAs, which, by means of RNA interference, direct the modification of proteins and DNA in heterochromatic repeats and transposable elements. Heterochromatin has thus emerged as a key factor in epigenetic regulation of gene expression, chromosome behaviour and evolution.

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Figure 1: Heterochromatin, transposable elements and PEV.
Figure 2: RNAi and heterochromatic silencing.

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Acknowledgements

We thank our collaborators V. Colot and A.-V. Gendrel, and members of our laboratory for discussions. We thank J. Birchler and S. Elgin for permission to reproduce Fig. 1, and A. Frary for comments on the manuscript. Z.L. is the recipient of an Arnold and Mabel Beckman Graduate Student Fellowship of the Watson School of Biological Sciences. R.M is supported by an NSF Plant Genome Program grant and an NIH grant.

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Lippman, Z., Martienssen, R. The role of RNA interference in heterochromatic silencing. Nature 431, 364–370 (2004). https://doi.org/10.1038/nature02875

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