PathwayStep154 PathwayStep153 PathwayStep156 PathwayStep155 PathwayStep158 PathwayStep157 Formation of SL1 Binding of Rrn3 to RNA Polymerase I Recruitment of Active RNA Polymerase I to SL1:phos.UBF-1:rDNA Promoter Acetylation of SL1 Recruitment of Acetylated SL1 to phosUBF-1:rDNA Promoter Assembly of RNA Polymerase I Holoenzyme (human) RNA Polymerase I Transcription Initiation Authored: Comai, L, 2003-07-03 17:13:29 During initiation the double-stranded DNA must be melted and transcription begins. SL1 forms and interacts with UBF-1 and the rDNA promoter. It is this platform that will recruit active RNA polymerase I to the SL1:phosphorlated UBF-1:rDNA promoter complex.<p>Mammalian rRNA genes are preceded by a terminator element that is recognized by the SL1 complex. This SL1 modulated acetylation of the basal Pol I transcription machinery has functional consequences suggesting that the reversible acetylation may be one way to regulate rDNA transcription. Edited: Gillespie, ME, 0000-00-00 00:00:00 GENE ONTOLOGYGO:0006361 Reactome Database ID Release 4373762 Reactome, http://www.reactome.org ReactomeREACT_953