2mh0 | pdb_00002mh0
Solution NMR structure of the p300 Taz2:ETAD1 complex
Structural highlights
Disease[TFE2_HUMAN] Precursor B-cell acute lymphoblastic leukemia. Chromosomal aberrations involving TCF3 are cause of forms of pre-B-cell acute lymphoblastic leukemia (B-ALL). Translocation t(1;19)(q23;p13.3) with PBX1. TCF3-PBX1 transforms cells by constitutively activating transcription of genes regulated by PBX1 or by other members of the PBX protein family. Translocation t(17;19)(q22;p13.3) with HLF. Inversion inv(19)(p13;q13) with TFPT. [EP300_HUMAN] Note=Defects in EP300 may play a role in epithelial cancer. Note=Chromosomal aberrations involving EP300 may be a cause of acute myeloid leukemias. Translocation t(8;22)(p11;q13) with KAT6A. Defects in EP300 are the cause of Rubinstein-Taybi syndrome type 2 (RSTS2) [MIM:613684]. A disorder characterized by craniofacial abnormalities, postnatal growth deficiency, broad thumbs, broad big toes, mental retardation and a propensity for development of malignancies. Some individuals with RSTS2 have less severe mental impairment, more severe microcephaly, and a greater degree of changes in facial bone structure than RSTS1 patients.[1] Function[TFE2_HUMAN] Transcriptional regulator. Involved in the initiation of neuronal differentiation. Heterodimers between TCF3 and tissue-specific basic helix-loop-helix (bHLH) proteins play major roles in determining tissue-specific cell fate during embryogenesis, like muscle or early B-cell differentiation. Dimers bind DNA on E-box motifs: 5'-CANNTG-3'. Binds to the kappa-E2 site in the kappa immunoglobulin gene enhancer. Binds to IEB1 and IEB2, which are short DNA sequences in the insulin gene transcription control region. [EP300_HUMAN] Functions as histone acetyltransferase and regulates transcription via chromatin remodeling. Acetylates all four core histones in nucleosomes. Histone acetylation gives an epigenetic tag for transcriptional activation. Mediates cAMP-gene regulation by binding specifically to phosphorylated CREB protein. Also functions as acetyltransferase for nonhistone targets. Acetylates 'Lys-131' of ALX1 and acts as its coactivator in the presence of CREBBP. Acetylates SIRT2 and is proposed to indirectly increase the transcriptional activity of TP53 through acetylation and subsequent attenuation of SIRT2 deacetylase function. Acetylates HDAC1 leading to its inactivation and modulation of transcription. Acts as a TFAP2A-mediated transcriptional coactivator in presence of CITED2. Plays a role as a coactivator of NEUROD1-dependent transcription of the secretin and p21 genes and controls terminal differentiation of cells in the intestinal epithelium. Promotes cardiac myocyte enlargement. Can also mediate transcriptional repression. Binds to and may be involved in the transforming capacity of the adenovirus E1A protein. In case of HIV-1 infection, it is recruited by the viral protein Tat. Regulates Tat's transactivating activity and may help inducing chromatin remodeling of proviral genes. Acetylates FOXO1 and enhances its transcriptional activity.[2] [3] [4] [5] [6] [7] [8] [9] [10] Publication Abstract from PubMedThe E-protein transcription factors guide immune cell differentiation, with E12 and E47 (hereafter called E2A) being essential for B-cell specification and maturation. E2A and the oncogenic chimera E2A-PBX1 contain three transactivation domains (ADs), with AD1 and AD2 having redundant, independent, and cooperative functions in a cell-dependent manner. AD1 and AD2 both mediate their functions by binding to the KIX domain of the histone acetyltransferase paralogues CREB-binding protein (CBP) and E1A-binding protein P300 (p300). This interaction is necessary for B-cell maturation and oncogenesis by E2A-PBX1 and occurs through conserved PhiXXPhiPhi motifs (with Phi denoting a hydrophobic amino acid) in AD1 and AD2. However, disruption of this interaction via mutation of the KIX domain in CBP/p300 does not completely abrogate binding of E2A and E2A-PBX1. Here, we determined that E2A-AD1 and E2A-AD2 also interact with the TAZ2 domain of CBP/p300. Characterization of the TAZ2:E2A-AD1(1-37) complex indicated that E2A-AD1 adopts an alpha-helical structure and uses its PhiXXPhiPhi motif to bind TAZ2. Whereas this region overlapped with the KIX recognition region, key KIX-interacting E2A-AD1 residues were exposed, suggesting that E2A-AD1 could simultaneously bind both the KIX and TAZ2 domains. However, we did not detect a ternary complex involving E2A-AD1, KIX, and TAZ2 and found that E2A containing both intact AD1 and AD2 is required to bind to CBP/p300. Our findings highlight the structural plasticity and promiscuity of E2A-AD1 and suggest that E2A binds both the TAZ2 and KIX domains of CBP/p300 through AD1 and AD2. Structural insights into TAZ2 domain-mediated CBP/p300 recruitment by transactivation domain 1 of the lymphopoietic transcription factor E2A.,Lochhead MR, Brown AD, Kirlin AC, Chitayat S, Munro K, Findlay JE, Baillie GS, LeBrun DP, Langelaan DN, Smith SP J Biol Chem. 2020 Mar 27;295(13):4303-4315. doi: 10.1074/jbc.RA119.011078. Epub, 2020 Feb 25. PMID:32098872[11] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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