DNA replication fork pause sites dependent on transcription

Replication fork pause (RFP) sites transiently arresting replication fork movement were mapped to transfer RNA (tRNA) genes of Saccharomyces cerevisiae in vivo, RFP sites are polar, stalling replication forks only when they oppose the direction of tRNA transcription, Mutant tRNA genes defective in assembly of transcription initiation complexes and a temperature-sensitive RNA polymerase III mutant (rpc160-41) defective in initiation of transcription do not stall replication forks, suggesting that transcription is required for RFP activity.