RNA polymerase III (Pol III) transcribes small untranslated RNAs, such as tRNAs. 
To define the Pol III transcriptome in Saccharomyces cerevisiae, we performed 
genome-wide chromatin immunoprecipitation using subunits of Pol III, TFIIIB and 
TFIIIC. Virtually all of the predicted targets of Pol III, as well as several 
novel candidates, were occupied by Pol III machinery. Interestingly, TATA 
box-binding protein occupancy was greater at Pol III targets than virtually all 
Pol II targets, and the highly occupied Pol II targets are generally strongly 
transcribed. The temporal relationships between factor occupancy and gene 
activity were then investigated at selected targets. Nutrient deprivation 
rapidly reduced both Pol III transcription and Pol III occupancy of both a tRNA 
gene and RPR1. In contrast, TFIIIB remained bound, suggesting that TFIIIB 
release is not a critical aspect of the onset of repression. Remarkably, TFIIIC 
occupancy increased dramatically during repression. Nutrient addition generally 
reestablished transcription and initial occupancy levels. Our results are 
consistent with active Pol III displacing TFIIIC, and with inactivation/release 
of Pol III enabling TFIIIC to bind, marking targets for later activation. These 
studies reveal new aspects of the kinetics, dynamics, and targets of the Pol III 
system.