Protein Phosphatase PP1 Regulation of Pol II Phosphorylation is Linked to Transcription Termination and Allelic Exclusion of VSG Genes and TERRA in Trypanosomes.

Base J is a modified DNA base that is enriched at RNA polymerase II termination sites. We previously found that base J functions to prevent readthrough transcription within gene clusters via the PJW/PP1 complex. Analysis of the complex in T. brucei faild to identify the catalytic PP1 component. We now show the RNAi ablation of PP1-1 in T. brucei leads to readthrough transcription and expression of downstream genes. The role of PP1-1 in regulating transcription termination was investigated using RNAi ablation in T. brucei cell lines. We used 6 RNA seq libraries to determine gene expression changes following the loss of PP1-1. As a control we used 6 RNA seq libraries to determine changes following the loss of PP1-7.