Transcription. Comment on "Mechanism of eukaryotic RNA polymerase III transcription termination".

Nielsen et al. (Reports, 28 June 2013, p. 1577) characterized their RNA polymerase III (Pol III) preparation and concluded that it requires an RNA hairpin/duplex structure for terminating transcription. We could not corroborate their findings using bona fide Pol III from two laboratory sources. We show that Pol III efficiently terminates transcription in the absence of a hairpin/duplex in vitro and in vivo.