Transcriptional intermediary factor

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. 

Among the proteins that form part of the transcription machinery are found some cell factors that are produced in limited quantities. They are called cofactors of transcription (NCoA, for nuclear-receptor coactivator NCoI, for nuclear-receptor coinhibitor), formerly known as transcription intermediary factors (TIF) (McDonnell et al. 2002 McKenna et al. 1999). They constitute one of the classes of proteins that form part of the transcription machinery. These proteins are utilized by diverse types of intensifiers, that is to say, by sequences of DNA that anchor transcription factors, of which HRE are a particular case (Gruber et al. 2002 Mester et al. 1995). They do not interact directly with the DNA, but they do with the receptors and with the other elements of the transcription apparatus (Fig. 1.9). 

VOM Baur, E., et al.. Differential ligand-dependent interactions between the AF-2 activating domain of nuclear receptors and the putative transcriptional intermediary factors mSUGl andTIFl. EmboJ, 1996, 15(1),... 

Abbreviations CBP, CREB binding protein CREB, cAMP response element binding protein FAT, factor acetyltransferase HAT, histone acetyltransferase MEL, mixed lineage leukaemia protein MORE, MOZ related factor MOZ, monocytic leukaemia zinc finger protein PHD, plant homeodomain RTS, Rubinstein-Taybi syndrome, TIE, transcription intermediary factor... 

TAS-108 (SR16234) is a novel and orally active steroidal compound with a proposed additional molecular mode-of-action that is different from that of SERMs such as tamoxifen and raloxifene [157]. TAS-108 is a full estrogen receptor-a antagonist, and it should also recruit co-activator transcriptional intermediary factor 2 to ER-j6, which may have a preventive effect on bone loss [157]. 

Germain-Desprez, D., Bazinet, M., Bouvier, M. and Aubry, M. (2003) Oligomerization of transcriptional intermediary factor 1 regulators and interaction with ZNF74 nuclear matrix protein revealed by bioluminescence resonance energy transfer in living cells. J. Biol. Chem. 278, 22367-22373. 

Transcription intermediary factor 2, a transcriptional coregulatory protein which contains several nuclear receptor interacting domains and an intrinsic histone acetyltransferase activity... 

Gustafsson, J.A., Hubbard, R.E., Brzozowski, A.M. and Pike, A.C. (2002) Interaction of transcriptional intermediary factor 2 nuclear receptor box peptides with the coactivator binding site of estrogen receptor a. The Journal of Biological Chemistry, 277, 21862—21868. 

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