Abstract
The discovery of millions of PIWI-interacting RNAs revealed a fascinating and unanticipated dimension of biology. The PIWI–piRNA pathway has been commonly perceived as germline-specific, even though the somatic function of PIWI proteins was documented when they were first discovered. Recent studies have begun to re-explore this pathway in somatic cells in diverse organisms, particularly lower eukaryotes. These studies have illustrated the multifaceted somatic functions of the pathway not only in transposon silencing but also in genome rearrangement and epigenetic programming, with biological roles in stem-cell function, whole-body regeneration, memory and possibly cancer.
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Acknowledgements
We thank S. Christensen, C. Juliano and S. Ramesh Mani for their critical reading of the manuscript. R.J.R. and M.M.W. are supported by an NIH Medical Scientist Training Program grant (T32-GM07205). The current work in the Lin lab on PIWIs and piRNA is supported by the NIH (DP1CA174418 and R01HD42012), the G. Harold & Leila Mathers Foundation, and an Ellison Medical Foundation Senior Scholar Award.
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Ross, R., Weiner, M. & Lin, H. PIWI proteins and PIWI-interacting RNAs in the soma. Nature 505, 353–359 (2014). https://doi.org/10.1038/nature12987
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DOI: https://doi.org/10.1038/nature12987
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