RNA Polymerase IV Directs Silencing of Endogenous DNA

@article{Herr2005RNAPI,
  title={RNA Polymerase IV Directs Silencing of Endogenous DNA},
  author={Alan J. Herr and M B Jensen and Tam{\'a}s Dalmay and David C. Baulcombe},
  journal={Science},
  year={2005},
  volume={308},
  pages={118 - 120}
}
Plants encode subunits for a fourth RNA polymerase (Pol IV) in addition to the well-known DNA-dependent RNA polymerases I, II, and III. By mutation of the two largest subunits (NRPD1a and NRPD2), we show that Pol IV silences certain transposons and repetitive DNA in a short interfering RNA pathway involving RNA-dependent RNA polymerase 2 and Dicer-like 3. The existence of this distinct silencing polymerase may explain the paradoxical involvement of an RNA silencing pathway in maintenance of… 
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TLDR
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