TTF-I:Sal Box Sal Box TTF-I binds to the Sal Box Authored: Comai, L, 2003-07-03 17:13:29 Edited: Gillespie, ME, 0000-00-00 00:00:00 Pubmed3458534 Pubmed7597036 Reactome Database ID Release 4374987 Reactome, http://www.reactome.org ReactomeREACT_768 The Transcription termination factor (TTF-1) binds an 18 base pair sequence element found in multiple copies in the nontranscribed spacer downstream of the 18S rRNA coding region. This element is the termination signal for ribosomal gene transcription. It is bound by TTF-I, which mediates the pausing of the elongating transcription complex.