In eukaryotes, RNA polymerases I, II and III synthesize RNAs, which are essential for life. Remarkably, plants have evolved two additional multisubunit RNA polymerases, RNA polymerases IV and V, to orchestrate non-coding RNA-mediated gene silencing processes. Their subunit compositions reveal that they evolved as specialized forms of RNA polymerase II.
- Jeremy R. Haag
- Craig S. Pikaard
