Histone acetyltransferase recruitment

Coactivators enhancing the transcriptional activity of steroid hormone receptors activators include SRC-1 (steroid-receptor co-activator 1) or TEF2 (transcriptional intermediary factor 2), which are recruited by the DNA/ steroid hormone receptor complex. Their main role is to attract other transcriptional coactivators with histone acetyltransferase activity in order to decondense chromatin and allow for the binding of components of the general transcription apparatus. 

Marzio G, Tyagi M, Gutierrez MI, Giacca M (1998) HIV-1 tat transactivator recruits p300 and CREB-binding protein histone acetyltransferases to the viral promoter. Proc Natl Acad Sd USA95(23) 13519-13524... 

The structure of the chromatin and their state of acetylation are important at the moment of initiating the gene transcription. Indeed, some of the transcription factors recruited by the receptor dimer have histone-acetyltransferase activity that permits the gene transcription after diminishing the condensation of the chromatin (Gruber et al. 2002 Nilsson et al. 2001 Vigushin et al. 2002). 

Qin S, Parthun MR (2006) Recruitment of the type B histone acetyltransferase Hatlp to chromatin is linked to DNA double-strand breaks. Mol.Cell.Biol 26 3649-3658... 

Bariev NA, Liu L, Chehab NH, Mansfield K, Harris KG, Halazonetis TD, Berger SL (2001) Acetylation of p53 activates transcription through recruitment of coactivators/histone acetyltransferases. Mol Cell 8 1243-1254... 

Frank SR, Paris T, Taubert S, Fernandez P, Fuchs M, Chan HM, Livingston DM, Amati B (2003) MYC recruits the TIP60 histone acetyltransferase complex to chromatin. EMBO Rep 4 575-580... 

Fig. 4 Co-activator and co-repressor complexes are required for nuclear hormone receptor-mediated transcriptional regulation. The tissue-selective fine-tuning of gene transcription by nuclear hormone receptors is due to different co-regulatory complexes that have various functions and enzymatic activities. Co-activator complexes include factors that contain ATP-dependent chromatin remodelling activity often associated with histone acetyltransferase (HAT) activity. Co-repressors include ATP-dependent chromatin remodelling complexes, which function as platforms for the recruitment of several subcomplexes that often contain histone deacetylase (HDAC) activity...

Figure 2.1 Schematic, simplified representation of the modulation of nuclear receptor functioning via classical agonists (a) resulting in the recruitment of coactivators featuring among others histone acetyltransferase (HATs) functionalities and via classical antagonists (b) resulting in the recruitment of corepressors...

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