5jem

Structural highlights

Disease

[CBP_HUMAN] Note=Chromosomal aberrations involving CREBBP may be a cause of acute myeloid leukemias. Translocation t(8;16)(p11;p13) with KAT6A; translocation t(11;16)(q23;p13.3) with MLL/HRX; translocation t(10;16)(q22;p13) with KAT6B. KAT6A-CREBBP may induce leukemia by inhibiting RUNX1-mediated transcription. Defects in CREBBP are a cause of Rubinstein-Taybi syndrome type 1 (RSTS1) [MIM:180849]. RSTS1 is an autosomal dominant disorder characterized by craniofacial abnormalities, broad thumbs, broad big toes, mental retardation and a propensity for development of malignancies.^{[1] [2] [3] [4]}

Function

[IRF3_HUMAN] Key transcriptional regulator of type I interferon (IFN)-dependent immune responses and plays a critical role in the innate immune response against DNA and RNA viruses. Regulates the transcription of type I IFN genes (IFN-alpha and IFN-beta) and IFN-stimulated genes (ISG) by binding to an interferon-stimulated response element (ISRE) in their promoters. Acts as a more potent activator of the IFN-beta (IFNB) gene than the IFN-alpha (IFNA) gene and plays a critical role in both the early and late phases of the IFNA/B gene induction. Found in an inactive form in the cytoplasm of uninfected cells and following viral infection, double-stranded RNA (dsRNA), or toll-like receptor (TLR) signaling, becomes phosphorylated by IKBKE and TBK1 kinases. This induces a conformational change, leading to its dimerization and nuclear localization and association with CREB binding protein (CREBBP) to form dsRNA-activated factor 1 (DRAF1), a complex which activates the transcription of the type I IFN and ISG genes. Can activate distinct gene expression programs in macrophages and can induce significant apoptosis in primary macrophages. [CBP_HUMAN] Acetylates histones, giving a specific tag for transcriptional activation. Also acetylates non-histone proteins, like NCOA3 and FOXO1. Binds specifically to phosphorylated CREB and enhances its transcriptional activity toward cAMP-responsive genes. Acts as a coactivator of ALX1 in the presence of EP300.^{[5] [6] [7] [8]}

References

1. ↑ Murata T, Kurokawa R, Krones A, Tatsumi K, Ishii M, Taki T, Masuno M, Ohashi H, Yanagisawa M, Rosenfeld MG, Glass CK, Hayashi Y. Defect of histone acetyltransferase activity of the nuclear transcriptional coactivator CBP in Rubinstein-Taybi syndrome. Hum Mol Genet. 2001 May 1;10(10):1071-6. PMID:11331617
2. ↑ Bartsch O, Locher K, Meinecke P, Kress W, Seemanova E, Wagner A, Ostermann K, Rodel G. Molecular studies in 10 cases of Rubinstein-Taybi syndrome, including a mild variant showing a missense mutation in codon 1175 of CREBBP. J Med Genet. 2002 Jul;39(7):496-501. PMID:12114483
3. ↑ Kalkhoven E, Roelfsema JH, Teunissen H, den Boer A, Ariyurek Y, Zantema A, Breuning MH, Hennekam RC, Peters DJ. Loss of CBP acetyltransferase activity by PHD finger mutations in Rubinstein-Taybi syndrome. Hum Mol Genet. 2003 Feb 15;12(4):441-50. PMID:12566391
4. ↑ Roelfsema JH, White SJ, Ariyurek Y, Bartholdi D, Niedrist D, Papadia F, Bacino CA, den Dunnen JT, van Ommen GJ, Breuning MH, Hennekam RC, Peters DJ. Genetic heterogeneity in Rubinstein-Taybi syndrome: mutations in both the CBP and EP300 genes cause disease. Am J Hum Genet. 2005 Apr;76(4):572-80. Epub 2005 Feb 10. PMID:15706485 doi:S0002-9297(07)62869-9
5. ↑ Zhang W, Bieker JJ. Acetylation and modulation of erythroid Kruppel-like factor (EKLF) activity by interaction with histone acetyltransferases. Proc Natl Acad Sci U S A. 1998 Aug 18;95(17):9855-60. PMID:9707565
6. ↑ Hung HL, Kim AY, Hong W, Rakowski C, Blobel GA. Stimulation of NF-E2 DNA binding by CREB-binding protein (CBP)-mediated acetylation. J Biol Chem. 2001 Apr 6;276(14):10715-21. Epub 2001 Jan 11. PMID:11154691 doi:10.1074/jbc.M007846200
7. ↑ Masumi A, Yamakawa Y, Fukazawa H, Ozato K, Komuro K. Interferon regulatory factor-2 regulates cell growth through its acetylation. J Biol Chem. 2003 Jul 11;278(28):25401-7. Epub 2003 May 7. PMID:12738767 doi:10.1074/jbc.M213037200
8. ↑ Iioka T, Furukawa K, Yamaguchi A, Shindo H, Yamashita S, Tsukazaki T. P300/CBP acts as a coactivator to cartilage homeoprotein-1 (Cart1), paired-like homeoprotein, through acetylation of the conserved lysine residue adjacent to the homeodomain. J Bone Miner Res. 2003 Aug;18(8):1419-29. PMID:12929931 doi:http://dx.doi.org/10.1359/jbmr.2003.18.8.1419