Tata-box-binding protein-associated factor 15 as a new potential marker in gastrointestinal tumors

Figure 1 The transcription activation complex involving tata-box-binding protein-associated factor 15, and its relationship with the mitogen-activated protein kinase signaling pathway. For the recruitment of RNA polymerase II to protein coding gene promoters, a sequential addition of specific general transcription factor is required. Transcription factor (TF) IID recognizes a specific sequence, the tata-box, and binds to this motif by tata-box binding protein (TBP) assisted by TBP-associated factors. This process creates a sharp bend in the promoter DNA. TBP recruits TFIIA, then TFIIB, to this promoter. TFIIB recruits RNA polymerase II and TFIIF to the promoter. TFIIE joins to this complex and recruits TFIIH leading to unwind DNA at promoter and form the transcription bubble. The template strand of the transcription bubble engages with the RNA polymerase II active site and RNA synthesis begins. TBP-associated factor 15 shuttles between the nucleus and cytoplasm, and promotes the proliferation, migration and invasion of tumor cells via the activation of RAF1/MEK/ERK signaling pathway. MAPK: Mitogen-activated protein kinase; TF: Transcription factor; TBP: Tata-box binding protein; TAF15: Tata-box-binding protein-associated factor 15.