An atypical RNA polymerase involved in RNA silencing shares small subunits with RNA polymerase II
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Updated: Jun 27, 2026

Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events
Published on: May 13, 2019
Linfeng Huang1, Alexandra M E Jones, Iain Searle
1The Sainsbury Laboratory, John Innes Centre, Colney Lane, Norwich NR4 7UH, UK.
Abstract:
Genetic evidence indicates that plant-specific homologs of DNA-dependent RNA polymerase (Pol) II large subunits form Pol IV and Pol V complexes involved in small interfering RNA production and RNA-directed DNA methylation. Here we describe evidence that Pol V contains subunits shared with Pol II, but that RNA polymerase II subunit (RPB)-4 is missing from Pol V and that RPB5 is present as a Pol V-specific isomer, RPB5b. Pol V also has other proteins that are not present in Pol II, consistent with a role of this complex as an effector of silencing.
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