Protein Degradation of RNA Polymerase II-Association Factor 1(PAF1) Is Controlled by CNOT4 and 26S Proteasome

• DOI: 10.1371/journal.pone.0125599
• Publication Date: 2015-05-01T18:09:40Z
• Authors: Hwa-Young Sun; Nari Kim; Cheol-Sang Hwang; Joo-Yeon Yoo
• Keywords: Protein Degradation; Degradation

The PAF complex (PAFc) participates in various steps of the transcriptional process, from initiation to termination, by interacting with and recruiting proteins proper locus for each step. PAFc is an evolutionarily conserved, multi-protein comprising PAF1, CDC73, CTR9, LEO1, yRTF1 and, humans, hSKI8. These components work together, their protein levels are closely interrelated. In present study, we investigated mechanism PAF1 degradation. We found that negatively regulated expression CNOT4, ortholog yNOT4 a member CCR4-NOT complex. CNOT4 specifically controls but not other at level regulating polyubiquitination its subsequent degradation 26S proteasome. was require nuclear localization, as no proteasome observed NLS (nucleus localization signal)-deficient mutants. However, chromatin binding necessary proteasome- or CNOT4-mediated Our results suggest chromatin-unbound via