The article discusses the general transcription factors (GTFs) of RNA polymerase II (pol II), which are essential for the initiation and regulation of mRNA transcription in eukaryotes. The GTFs, collectively known as TFIIA, TFIIIB, TFIIID, TFIIIE, TFIIIF, and TFIIH, are required for the formation of preinitiation complexes that recruit pol II to promoters. The assembly of these factors onto promoter DNA is a complex process involving multiple steps and interactions. TFIIID, the first factor to bind the promoter, recognizes core promoter elements such as the TATA box and the initiator motif. TFIIIB then binds to the TFIID-promoter complex, followed by TFIIIA, which stabilizes the TBP-promoter complex. TFIIIF escorts pol II to the promoter and plays a role in elongation. TFIIIE and TFIIH complete the preinitiation complex, enabling pol II to initiate transcription. The article also highlights the structural and functional similarities between TFIIIF and bacterial σ factors, suggesting a common evolutionary origin. Additionally, it discusses the energy requirements for transcription initiation, emphasizing the role of ATP hydrolysis and the phosphorylation of the CTD (carboxy-terminal domain) of pol II.The article discusses the general transcription factors (GTFs) of RNA polymerase II (pol II), which are essential for the initiation and regulation of mRNA transcription in eukaryotes. The GTFs, collectively known as TFIIA, TFIIIB, TFIIID, TFIIIE, TFIIIF, and TFIIH, are required for the formation of preinitiation complexes that recruit pol II to promoters. The assembly of these factors onto promoter DNA is a complex process involving multiple steps and interactions. TFIIID, the first factor to bind the promoter, recognizes core promoter elements such as the TATA box and the initiator motif. TFIIIB then binds to the TFIID-promoter complex, followed by TFIIIA, which stabilizes the TBP-promoter complex. TFIIIF escorts pol II to the promoter and plays a role in elongation. TFIIIE and TFIIH complete the preinitiation complex, enabling pol II to initiate transcription. The article also highlights the structural and functional similarities between TFIIIF and bacterial σ factors, suggesting a common evolutionary origin. Additionally, it discusses the energy requirements for transcription initiation, emphasizing the role of ATP hydrolysis and the phosphorylation of the CTD (carboxy-terminal domain) of pol II.