FOX proteins

From Wikipedia, the free encyclopedia

Forkhead box proteins (FOX proteins) are a family of transcription factors that play important roles in regulating the expression of genes involved in cell growth, proliferation, differentiation, and longevity. Many FOX proteins are important to embryonic development.


The defining feature of FOX proteins is the forkhead box, a sequence of 80 to 100 amino acids forming a motif that binds to DNA. This forkhead motif is also known as the winged helix due to the butterfly-like appearance of the loops in the protein structure of the domain.[1] Forkhead genes are a subgroup of the helix-turn-helix class of proteins.

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[edit] Biological roles

Many other genes encoding FOX proteins have been identified. For example, the FOXF2 gene encodes forkhead box F2, one of many human homologues of the Drosophila melanogaster transcription factor forkhead. FOXF2 is expressed in lung and placenta.

Some FOX genes are downstream targets of the hedgehog signaling pathway, which plays a role in the development of basal cell carcinomas. Members of the class O regulate metabolism, cellular proliferation, stress tolerance and probably lifespan. The activity of FoxO is controlled by post-translational modifications, including phosphorylation, acetylation and ubiquitylation[2].

[edit] History

The first protein in the FOX family that was discovered was the fork head transcription factor in Drosophila (thus the name). Since then a large number of family members have been discovered, especially in vertebrates. Originally they were given vastly different names (such as HFH, FREAC, and fkh), but in 2000 a unified nomenclature was introduced that grouped the FOX proteins into subclasses (FOXA-FOXS) based on sequence conservation.[3]

[edit] Genes

[edit] References

  1. ^ Lehmann OJ, Sowden JC, Carlsson P, Jordan T, Bhattacharya SS (2003). "Fox's in development and disease". TRENDS in Genetics 19 (6): 339-344. doi:10.1016/S0168-9525(03)00111-2. PMID 12801727. 
  2. ^ van der Horst A, Burgering BM. Stressing the role of FoxO proteins in lifespan and disease. Nat Rev Mol Cell Biol. 2007; 8:440-450.
  3. ^ Kaestner KH, Knochel W, Martinez DE (2000). "Unified nomenclature for the winged helix/forkhead transcription factors.". Genes and Development 14: 142-146. PMID 10702024. 

[edit] Further reading

[edit] External links


v • d • e
Transcription factors and intracellular receptors
(1) Basic domains
(1.1) Basic leucine zipper (bZIP)
Activating transcription factor (AATF, 1, 2, 3, 4, 5, 6, 7) • AP-1 (c-Fos, FOSB, FOSL1, FOSL2, c-Jun, JUNB, JUND) • BACH (1, 2) • BATF • BLZF1 • C/EBP (α, β, γ, δ, ε, ζ) • CREB (1, 3, L1) • CREM • DBP • DDIT3 • GABPA • HLF • MAF (B, F, G, K) • NFE (2, L1, L2) • NRL • NRF1 • XBP1
(1.2) Basic helix-loop-helix (bHLH)
ATOH1 • AhR • AHRR • ARNT • ASCL1 • BHLHB2 • BMAL (ARNTL, ARNTL2) • CLOCK • EPAS1 • HAND (1, 2) • HES (5, 6) • HEY (1, 2, L) • HES1 • HIF (1A, 3A) • ID (1, 2, 3, 4) • LYL1 • MXD4 • MYCL1 • MYCN • Myogenic regulatory factors (MyoD, Myogenin, MYF5, MYF6) • Neurogenins • NeuroD (1, 2) • NPAS (1, 2, 3) • OLIG (1, 2) • Scleraxis • TAL1 • Twist • USF1
(1.3) bHLH-ZIP
MAX • MITF • MNT • MLX • MXI1 • Myc • SREBP (1, 2)
(1.6) Basic helix-span-helix (bHSH)
(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) • MTA (1, 2, 3)
(2.3) Cys2His2
ATBF1 • BCL(6, 11A, 11B) • CTCF • E4F1 • EGR (2, 3) • ERV3 • General transcription factors (TFIIA, TFIIB, TFIID, TFIIE, TFIIF: 1, 2, TFIIH: 1, 2, 4, 2I, 3A, 3C1, 3C2) • GFI1 • GLI-Krüppel family (1, 2, 3, YY1) • HIC (1, 2) • HIVEP (1, 2, 3) • IKZF (1, 2, 3) • ILF (2, 3) • KLF (2, 4, 5, 6, 9, 10, 11, 12, 13) • MTF1 • MYT1 • OSR1 • Sp1 • zinc finger ((3, 7, 9, 10, 19, 22, 24, 33B, 34, 35, 41, 43, 44, 51, 74, 143, 146, 148, 165, 202, 217, 219, 238, 239, 259, 267, 268, 281, 295, 318, 330, 346, 350, 365, 366, 384, 451, 452, 471, 593, 638, 649, 655) • Zbtb7 (7A) • ZBT (16, 17, 33)
(2.4) Cys6
(2.5) Alternating composition
AIRE • DIDO1 • GRLF1 • ING (1, 2, 4) • JARID (1A, 1B, 1C, 1D, 2) • JMJD1B
(3) Helix-turn-helix
domains
ARX • CDX (1, 2) • CRX • CUTL1 • DLX (3, 4, 5) • EMX2 • EN (1, 2) • FHL (1, 2, 3) • HESX1 • HHEX • HLX • Homeobox (A1, A3, A4, A5, A7, A9, A10, A11, A13, B1, B2, B3, B4, B5, B6, B7, B8, B9, B13, C4, C5, C6, C8, C9, C10, C11, C13, D1, D3, D4, D8, D9, D10, D11, D12, D13) • HOPX • MEIS (1, 2) • MEOX2 • MNX1 • MSX (1, 2) • NANOG • NKX (2-1, 2-5, 3-1) • PHF (3, 6, 10, 17) • POU domain (PIT-1, BRN-3: 1, 2, Octamer transcription factor: 1, 2, 3/4, 6, 7) • OTX (1, 2) • PDX1
(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, K2, L2, M1, N3, O1A, , O3A, O4, P1, P2, P3)
HSF (1, 2, 4)
(3.5) Tryptophan clusters
ELF (4, 5) • EGF • ELK (1, 3, 4) • ERF • ERG • ETS (1, 2) • ETV (1, 4, 5, 6) • FLI1 • Interferon regulatory factors (1, 2, 3, 4, 5, 6, 7, 8) • MYB • MYBL2
(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 (C1, C2, C3, C4, 5)
(4.2) STAT
STAT (1, 2, 3, 4, 5, 6)
(4.3) p53
(4.4) MADS box
Mef2 (A, B, C, D) • SRF
HNF (1A, 1B) • LEF1 • SOX (2, 3, 4, 5, 6, 8, 9, 10, 11, 13, 15, 18) • SRY • SSRP1
(4.10) Cold-shock domain
(4.11) Runt
(0) Other
transcription factors
(0.2) HMGI(Y)
HMGA (1, 2) • HBP1
Rb • RBL1 • RBL2
(0.5) AP-2/EREBP-related factors
Apetala 2 • EREBP • B3
(0.6) Miscellaneous
ARID (1A, 1B, 2, 3A, 3B, 4A) • CAP • IFI (16, 35) • MLL (2, 3, T1) • MNDA • NFI (A, B, C, X) • NFY (A, B, C) • Rho/Sigma • R-SMAD
Languages