PPP1R10 (PNUTS) functions as a substrate-recognition component of the PNUTS-PP1 protein phosphatase complex, which regulates RNA polymerase II transcription through multiple mechanisms 1. The complex promotes transcription pause-release by dephosphorylating key proteins including AFF4, CDK9, and SUPT6H, allowing RNA polymerase II to transition from promoter-proximal pausing to productive elongation 1. Additionally, PNUTS-PP1 regulates transcription termination and responds to replication stress 2. PPP1R10 also serves as a nuclear targeting subunit for the complex and can act as a PP1 inhibitor in certain contexts 3. The protein undergoes histidine methylation by CARNMT1, which may modulate its function 4. Clinically, PPP1R10 expression is associated with DNA repair mechanisms and genomic stability. Reduced PPP1R10 levels correlate with radiotherapy resistance in breast cancer through modulation of the ATR pathway and Chek1/P53 checkpoint activation 5. Age-related changes in hepatic PPP1R10 expression suggest its involvement in aging processes, with the gene proposed as part of an 'aging cascade' 6. Alternative polyadenylation of PPP1R10 has been identified as a potential susceptibility factor in non-small cell lung cancer 7.