General transcription factor

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General transcription factors (GTF's) are protein transcription factors which have been shown to be important in the transcription of class II genes to mRNA templates. Many of them are involved in the formation of a preinitiation complex, which, together with RNA polymerase II, bind to and read the single-stranded DNA gene template.^[1]

Functions

GTF's are intimately involved in the process of gene regulation, and most are required for life. Tata binding protein, (TBP) is a GTF that binds to the TATAA box (T=Thymine, A=Adenine) the motif of nucleic acids that is directly upstream from the coding region in all genes. TBP is responsible for the recruitment of the RNA Pol II holoenzyme, the final event in transcription initiation. These proteins are ubiquitous and interact with the core promoter region of DNA, which contains the transcription start site(s) of all class II genes.

Not all GTFs play a role in transcriptional initiation; some are required for the second general step in transcription, elongation. For example, members of the FACT complex, Spt16/Pob3, facilitate the rapid movement of RNA Pol II over the encoding region of genes. This is accomplished by moving the histone octamer out of the way of an active polymerase and thereby decondensing the chromatin.

Types

The most common general transcription factors are:

TFIIA (see also TFIIA; TFIIA is not a real basal transcription factor.)
TFIIB (see also TFIIB)
TFIID (see also TFIID)
TFIIE (see also TFIIE)
TFIIF (see also TFIIF)
TFIIH (see also TFIIH)
Spt16
TBP (also known as Spt15)

Note: Basal transcription in test tubes has been achieved using only highly-purified recombinant TFIIB and TFIIF.

References

↑ Orphanides G, Lagrange T, Reinberg D (1996). "The general transcription factors of RNA polymerase II". Genes Dev. 10 (21): 2657-83. doi:10.1101/gad.10.21.2657. PMID 8946909.

External links

http://www.yeastgenome.org has highly detailed information on most known GTF's and is an excellent resource for students and researchers alike
MeSH General+Transcription+Factors

v • d • e Cell signaling
Key concepts	Ligand - Signal transduction - Apoptosis - Second messenger system (Ca²⁺ signaling, Lipid signaling)
Processes	Paracrine - Autocrine - Juxtacrine - Neurotransmitters - Endocrine (Neuroendocrine)
Types of proteins	Receptor (Transmembrane, Intracellular) - Transcription factor (General, Preinitiation complex, TFIID, TFIIH) - Adaptor protein
receptor ligands	hormones, neurotransmitters, cytokines, growth factors

v • d • e

Transcription factors and intracellular receptors

(1) Basic domains

(1.1) Basic leucine zipper (bZIP)	Activating transcription factor (1, 2, 3, 4, 5, 6) • AP-1 (c-Fos, FOSB, FOSL1, FOSL2, c-Jun, JUNB, JUND) • BACH (1, 2) • C/EBP (α, β, γ, δ, ε, ζ) • CREB (1, 3) • GABPA • MAF (B, F, G, K) • NRL • NRF1 • XBP1
(1.2) Basic helix-loop-helix (bHLH)	ATOH1 • AhR • AHRR • ARNT • ASCL1 • BMAL (ARNTL, ARNTL2) • CLOCK • HIF (1A, 3A) • Myogenic regulatory factors (MyoD, Myogenin, MYF5, MYF6) • NEUROD1 • Twist • USF1
(1.3) bHLH-ZIP	Myc • MITF • SREBP (1, 2)
(1.6) Basic helix-span-helix (bHSH)	AP-2

(2) Zinc finger
DNA-binding domains

(2.1) Nuclear receptor (Cys₄)	subfamily 1 (Thyroid hormone (α, β), CAR, FXR, LXR (α, β), PPAR (α, β/δ, γ), PXR, RAR (α, β, γ), ROR (α, β, γ), Rev-ErbA (α, β), VDR) • subfamily 2 (COUP-TF (I, II), Ear-2, HNF4 (α, γ), PNR, RXR (α, β, γ), Testicular receptor (2, 4), TLX) • subfamily 3 (Steroid hormone (Estrogen (α, β), Estrogen related (α, β, γ), Androgen, Glucocorticoid, Mineralocorticoid, Progesterone)) • subfamily 4 NUR (NGFIB, NOR1, NURR1) • subfamily 5 (LRH-1, SF1) • subfamily 6 (GCNF) • subfamily 0 (DAX1, SHP)
(2.2) Other Cys₄	GATA (1, 2, 3, 4, 5, 6)
(2.3) Cys₂His₂	General transcription factors (TFIIA, TFIIB, TFIID, TFIIE, TFIIF, TFIIH: 1, 2) • GLI-Krüppel family (1, 2, 3, YY1) • KLF (2, 4, 5, 6, 10, 11, 12, 13) • Sp1 • zinc finger (3, 35, 43, 146, 148, 165, 217, 268, 281, 350) • Zbtb7 (7A) • ZBT (16, 17, 33)
(2.4) Cys₆	HIVEP1

(3) Helix-turn-helix
domains

(3.1) Homeo domain	ARX • Homeobox (A1, A3, A4, A5, A7, A9, A10, A11, A13, B1, B2, B3, B4, B5, B6, B7, B8, B9, B13, C4, C6, C8, C9, C13, D1, D3, D4, D9, D10, D11, D12, D13) • NANOG • NKX (2-1, 2-5, 3-1) • POU domain (PIT-1, BRN-3: 1, 2, Octamer transcription factor: 1, 2, 3/4, 6, 7)
(3.2) Paired box	PAX (1, 2, 3, 4, 5, 6, 7, 8, 9)
(3.3) Fork head / winged helix	E2F (1, 2, 3, 4, 5) • FOX proteins (C1, C2, E1, G1, H1, L2, M1, N3, O3, O4, P1, P2, P3)
(3.4) Heat Shock Factors	HSF1
(3.5) Tryptophan clusters	ELF (4, 5) • Interferon regulatory factors (1, 2, 3, 4, 5, 6, 7, 8) • MYB
(3.6) TEA domain	transcriptional enhancer factor 1, 2

(4) β-Scaffold factors with
minor groove contacts

(4.1) Rel homology region	NF-κB (NFKB1, NFKB2, REL, RELA, RELB) • NFAT (5, C1, C2, C3, C4)
(4.2) STAT	STAT (1, 2, 3, 4, 5, 6)
(4.3) p53	p53
(4.4) MADS box	Mef2 (A, B, C, D) • SRF
(4.7) High mobility group	HNF (1A, 1B) • LEF1 • SOX (3, 4, 6, 9, 10, 13, 18) • SRY • SSRP1
(4.10) Cold-shock domain	CSDA

(0) Other
transcription factors

(0.2) HMGI(Y)	HMGA (1, 2)
(0.3) Pocket domain	Rb • RBL1 • RBL2
(0.6) Miscellaneous	ARID (1A, 1B, 2, 3A, 3B, 4A) • CAP • Rho/Sigma • R-SMAD