UBF (F2F1O) Rabbit mAb #35663

RNA polymerase I (RNAPI) is a large multi-protein complex that functions as a DNA-dependent, RNA polymerase, which is primarily responsible for the transcription of ribosomal RNA (rRNA) genes. The largest subunit, Rpa194, or POLR1A, along with selectivity factor 1 (SL1) and the transactivator protein upstream binding factor (UBF), makes up the core transcriptional machinery of the RNAPI complex (1-3). UBF is a nucleolar protein that functions as a dual transcription factor and epigenetic remodeler to promote rRNA transcription (4). ChIP-seq studies show that UBF binds ribosomal DNA (rDNA) at the promoter sequence and throughout the transcribed regions (4,5). At the promoter region, UBF associates with SL1 to drive formation of the preinitiation complex (PIC) (6,7). UBF also promotes rRNA transcription by displacing linker histone H1 and keeping rDNA in an active euchromatin state (8,9). Due to its critical role in ribosome biogenesis, defects in UBF have been linked to several ribosomopathies and neurological disorders (10). Specifically, a gain-of-function E210K mutation in UBF has been linked to multiple cases of pediatric neurodegeneration (11).