TAFII55 binding to TAFII250 inhibits its acetyltransferase activity

AUTOR(ES)

Gegonne, Anne

FONTE

The National Academy of Sciences

RESUMO

The general transcription factor, TFIID, consists of the TATA-binding protein (TBP) associated with a series of TBP-associated factors (TAFs) that together participate in the assembly of the transcription preinitiation complex. One of the TAFs, TAFII250, has acetyltransferase (AT) activity that is necessary for transcription of MHC class I genes: inhibition of the AT activity represses transcription. To identify potential cellular factors that might regulate the AT activity of TAFII250, a yeast two-hybrid library was screened with a TAFII250 segment (amino acids 848-1279) that spanned part of its AT domain and it's the domain that binds to the protein, RAP74. The TFIID component, TAFII55, was isolated and found to interact predominantly with the RAP74-binding domain. TAFII55 binding to TAFII250 inhibits its AT activity. Importantly, the addition of recombinant TAFII55 to in vitro transcription assays inhibits TAFII250-dependent MHC class I transcription. Thus, TAFII55 is capable of regulating TAFII250 function by modulating its AT activity.

Documentos Relacionados

• Requirement for TAFII250 Acetyltransferase Activity in Cell Cycle Progression
• Requirement for TAFII250 Acetyltransferase Activity in Cell Cycle Progression
• Rb Inhibits the Intrinsic Kinase Activity of TATA-Binding Protein-Associated Factor TAFII250
• HIV-1 Tat binds TAFII250 and represses TAFII250-dependent transcription of major histocompatibility class I genes
• Sp1 and AP2 regulate but do not constitute TATA-less human TAFII55 core promoter activity