The Human RNA Polymerase I Transcription Terminator Complex Acts as a Replication Fork Barrier That Coordinates the Progress of Replication with rRNA Transcription Activity.

ABSTRACT: In S phase, the replication and transcription of genomic DNA need to accommodate each other, otherwise their machineries collide, with chromosomal instability as a possible consequence. Here, we characterized the human replication fork barrier (RFB) that is present downstream from the 47S pre-rRNA gene (ribosomal DNA [rDNA]). We found that the most proximal transcription terminator, Sal box T1, acts as a polar RFB, while the other, Sal box T4/T5, arrests replication forks bidirectionally. The fork-arresting activity at these sites depends on polymerase I (Pol I) transcription termination factor 1 (TTF-1) and a replisome component, TIMELESS (TIM). We also found that the RFB activity was linked to rDNA copies with hypomethylated CpG and coincided with the time that actively transcribed rRNA

SUBMITTER: Akamatsu Y 

PROVIDER: S-EPMC4405639 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature