TAFII-18 Inhibitors

Chemical inhibitors of TATA Box Binding Protein (TBP)-Associated Factor, 18kDa (TAFII-18) can disrupt the protein's function through various mechanisms. Trichostatin A, an HDAC inhibitor, can lead to a hyperacetylated state of histones, which in turn can prevent TAFII-18 from correctly assembling into the transcription factor complex due to altered chromatin structure. Similarly, I-CBP112 and SGC-CBP30 can inhibit the BET family of bromodomain proteins, potentially altering chromatin structure and recruitment of TAFII-18 to transcriptional start sites by disrupting interaction with acetylated lysines on histone tails. JQ1, another BET bromodomain inhibitor, can competitively bind to the acetyl-lysine recognition pocket of BET bromodomains, disrupting the recruitment and function of TAFII-18 within the transcription complex.

Additionally, Triptolide can inhibit the activity of XPB, a subunit of the transcription factor TFIIH, which is integral to the initiation of transcription, subsequently reducing the functional incorporation of TAFII-18 into the pre-initiation complex. Pladienolide B can bind to the SF3b complex of the spliceosome, indirectly reducing the functional presence of TAFII-18 by impacting the post-transcriptional processing of mRNAs that encode components of the TAF complex. Selinexor, an XPO1 inhibitor, can alter the nuclear export of proteins and RNA species, affecting the subcellular localization and availability of TAFII-18. Cyclin-dependent kinase inhibitors such as Flavopiridol, THZ1, and Dinaciclib can impede necessary phosphorylation events for the proper function and recruitment of TAFII-18 to the transcription initiation complex. CK2 inhibitor CX-4945 can disrupt protein-protein interactions within the transcriptional machinery, impacting TAFII-18's function in the transcription complex. Finally, Silvestrol, an inhibitor of eIF4A, can disrupt the initiation of translation, indirectly reducing the synthesis of specific transcriptional coactivators necessary for TAFII-18 function. Each of these inhibitors can lead to the functional inhibition of TAFII-18 by targeting different aspects of its role in the transcription initiation process.