151
|
Wei L, Jamonnak N, Choy J, Wang Z, Zheng W. Differential binding modes of the bromodomains of CREB-binding protein (CBP) and p300 with acetylated MyoD. Biochem Biophys Res Commun 2008; 368:279-84. [PMID: 18222173 DOI: 10.1016/j.bbrc.2008.01.071] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2008] [Accepted: 01/13/2008] [Indexed: 11/30/2022]
Abstract
The recruitment of the bromodomains of CREB-binding protein (CBP) and p300 by the acetylated myogenic transcription factor MyoD was previously shown to be critical for the enhanced MyoD transcriptional activity following acetylation at its Lys99 and Lys102 positions. However, the modes of binding interactions of the bromodomains of CBP and p300 with acetylated MyoD have not been well-characterized. In the current study, by employing a panel of MyoD peptides encompassing the 99 and 102 positions, we showed that Lys99 monoacetylation and Lys99/Lys102 double acetylation defined the critical binding interfaces with the bromodomains of CBP and p300, respectively. This also represented the first identification of a recognition motif for the p300 bromodomain and revelation of the differential recognition motifs for the bromodomains of CBP and p300. This information could be exploited for developing novel tools for structural and functional studies of the highly homologous CBP and p300 transcriptional coactivators.
Collapse
Affiliation(s)
- Lanlan Wei
- Department of Chemistry, University of Akron, 109 East Buchtel Commons, Akron, OH 44325, USA
| | | | | | | | | |
Collapse
|
152
|
Abstract
Transcriptional networks orchestrate fundamental biological processes, including hematopoiesis, in which hematopoietic stem cells progressively differentiate into specific progenitors cells, which in turn give rise to the diverse blood cell types. Whereas transcription factors recruit coregulators to chromatin, leading to targeted chromatin modification and recruitment of the transcriptional machinery, many questions remain unanswered regarding the underlying molecular mechanisms. Furthermore, how diverse cell type-specific transcription factors function cooperatively or antagonistically in distinct cellular contexts is poorly understood, especially since genes in higher eukaryotes commonly encompass broad chromosomal regions (100 kb and more) and are littered with dispersed regulatory sequences. In this article, we describe an important set of transcription factors and coregulators that control erythropoiesis and highlight emerging transcriptional mechanisms and principles. It is not our intent to comprehensively survey all factors implicated in the transcriptional control of erythropoiesis, but rather to underscore specific mechanisms, which have potential to be broadly relevant to transcriptional control in diverse systems.
Collapse
|
153
|
Elliott AM, de Miguel MP, Rebel VI, Donovan PJ. Identifying genes differentially expressed between PGCs and ES cells reveals a role for CREB-binding protein in germ cell survival. Dev Biol 2007; 311:347-58. [DOI: 10.1016/j.ydbio.2007.08.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Revised: 08/11/2007] [Accepted: 08/14/2007] [Indexed: 12/30/2022]
|
154
|
Oliveira AM, Wood MA, McDonough CB, Abel T. Transgenic mice expressing an inhibitory truncated form of p300 exhibit long-term memory deficits. Learn Mem 2007; 14:564-72. [PMID: 17761541 PMCID: PMC1994075 DOI: 10.1101/lm.656907] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The formation of many forms of long-term memory requires several molecular mechanisms including regulation of gene expression. The mechanisms directing transcription require not only activation of individual transcription factors but also recruitment of transcriptional coactivators. CBP and p300 are transcriptional coactivators that interact with a large number of transcription factors and regulate transcription through multiple mechanisms, including an intrinsic histone acetyltransferase (HAT) activity. HAT activity mediates acetylation of lysine residues on the amino-terminal tails of histone proteins, thereby increasing DNA accessibility for transcription factors to activate gene expression. CBP has been shown to play an important role in long-term memory formation. We have investigated whether p300 is also required for certain forms of memory. p300 shares a high degree of homology with CBP and has been shown to interact with transcription factors known to be critical for long-term memory formation. Here we demonstrate that conditional transgenic mice expressing an inhibitory truncated form of p300 (p300Delta1), which lacks the carboxy-terminal HAT and activation domains, have impaired long-term recognition memory and contextual fear memory. Thus, our study demonstrates that p300 is required for certain forms of memory and that the HAT and carboxy-terminal domains play a critical role.
Collapse
Affiliation(s)
- Ana M.M. Oliveira
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Gulbenkian Ph.D. Programme in Biomedicine, Instituto Gulbenkian de Ciência, 2781-901 Oeiras, Portugal
| | - Marcelo A. Wood
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, Irvine, California 92697, USA
| | - Conor B. McDonough
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Ted Abel
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Corresponding author.E-mail ; fax (215) 898-8780
| |
Collapse
|
155
|
Abstract
Rubinstein-Taybi syndrome is characterised by mental retardation, growth retardation and a particular dysmorphology. The syndrome is rare, with a frequency of approximately one affected individual in 100,000 newborns. Mutations in two genes - CREBBP and EP300 - have been identified to cause the syndrome. These two genes show strong homology and encode histone acetyltransferases (HATs), which are transcriptional co-activators involved in many signalling pathways. Loss of HAT activity is sufficient to account for the phenomena seen in Rubinstein-Taybi patients. Although some mutations found in CREBBP are translocations, inversions and large deletions, most are point mutations or small deletions and insertions. Mutations in EP300 are comparatively rare. Extensive screening of patients has revealed mutations in CREBBP and EP300 in around 50% of cases. The cause of the syndrome in the remaining patients remains to be identified, but other genes could also be involved. Here, we describe the clinical presentation of Rubinstein-Taybi syndrome, review the mutation spectrum and discuss the current understanding of causative molecular mechanisms.
Collapse
|
156
|
Screening of aplastic anaemia-related genes in bone marrow CD4+T cells by suppressive subtractive hybridization. Chin Med J (Engl) 2007. [DOI: 10.1097/00029330-200708010-00006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
157
|
Cvekl A, Duncan MK. Genetic and epigenetic mechanisms of gene regulation during lens development. Prog Retin Eye Res 2007; 26:555-97. [PMID: 17905638 PMCID: PMC2136409 DOI: 10.1016/j.preteyeres.2007.07.002] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Recent studies demonstrated a number of links between chromatin structure, gene expression, extracellular signaling and cellular differentiation during lens development. Lens progenitor cells originate from a pool of common progenitor cells, the pre-placodal region (PPR) which is formed from a combination of extracellular signaling between the neural plate, naïve ectoderm and mesendoderm. A specific commitment to the lens program over alternate choices such as the formation of olfactory epithelium or the anterior pituitary is manifested by the formation of a thickened surface ectoderm, the lens placode. Mouse lens progenitor cells are characterized by the expression of a complement of lens lineage-specific transcription factors including Pax6, Six3 and Sox2, controlled by FGF and BMP signaling, followed later by c-Maf, Mab21like1, Prox1 and FoxE3. Proliferation of lens progenitors together with their morphogenetic movements results in the formation of the lens vesicle. This transient structure, comprised of lens precursor cells, is polarized with its anterior cells retaining their epithelial morphology and proliferative capacity, whereas the posterior lens precursor cells initiate terminal differentiation forming the primary lens fibers. Lens differentiation is marked by expression and accumulation of crystallins and other structural proteins. The transcriptional control of crystallin genes is characterized by the reiterative use of transcription factors required for the establishment of lens precursors in combination with more ubiquitously expressed factors (e.g. AP-1, AP-2alpha, CREB and USF) and recruitment of histone acetyltransferases (HATs) CBP and p300, and chromatin remodeling complexes SWI/SNF and ISWI. These studies have poised the study of lens development at the forefront of efforts to understand the connections between development, cell signaling, gene transcription and chromatin remodeling.
Collapse
Affiliation(s)
- Ales Cvekl
- Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | | |
Collapse
|
158
|
Xu W, Kasper LH, Lerach S, Jeevan T, Brindle PK. Individual CREB-target genes dictate usage of distinct cAMP-responsive coactivation mechanisms. EMBO J 2007; 26:2890-903. [PMID: 17525731 PMCID: PMC1894772 DOI: 10.1038/sj.emboj.7601734] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Accepted: 05/03/2007] [Indexed: 11/09/2022] Open
Abstract
CREB is a key mediator of cAMP- and calcium-inducible transcription, where phosphorylation of serine 133 in its Kinase-Inducible Domain (KID) is often equated with transactivation. Phospho-Ser133 is required for CREB to bind the KIX domain of the coactivators CBP and p300 (CBP/p300) in vitro, although the importance of this archetype coactivator interaction for endogenous gene expression is unclear. Here, we show that the CREB interaction with KIX is necessary for only a part of cAMP-inducible transcription and CBP/p300 recruitment. Surprisingly, individual cAMP-inducible genes with CREB bound at their promoters differed in their reliance on KIX and none examined showed complete dependence. Alternatively, we found that arginine 314 (Arg314) in the CREB basic-leucine zipper (bZIP) domain contributed to CBP/p300 recruitment and KIX-independent CREB transactivation function. This implicates Transducer Of Regulated CREB (TORC), an unrelated cAMP-responsive coactivator that binds via Arg314, and which can bind CBP/p300, in these functions. Interestingly, KIX was also required for the full cAMP induction of a gene that did not require CREB. Thus, individual CREB-target gene context dictates the relative contribution of at least two different cAMP-responsive coactivation mechanisms.
Collapse
Affiliation(s)
- Wu Xu
- Department of Biochemistry, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Lawryn H Kasper
- Department of Biochemistry, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Stephanie Lerach
- Department of Biochemistry, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Trushar Jeevan
- Department of Biochemistry, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Paul K Brindle
- Department of Biochemistry, St Jude Children's Research Hospital, Memphis, TN, USA
| |
Collapse
|
159
|
Fonte C, Trousson A, Grenier J, Schumacher M, Massaad C. Opposite effects of CBP and p300 in glucocorticoid signaling in astrocytes. J Steroid Biochem Mol Biol 2007; 104:220-7. [PMID: 17475479 DOI: 10.1016/j.jsbmb.2007.03.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In the nervous system, glucocorticoid hormones play a major role during development, and they continue to affect functional and structural plasticity throughout life. Glucocorticoid actions are mediated by their cognate nuclear receptor, the glucocorticoid receptor (GR). The transcriptional activity of the GR is enhanced by the recruitment of one of the transcriptional coactivators of the p160 family (SRCs), which are a docking platform for secondary coactivators like CBP, or its close homologue p300. Here, we investigated the implication of CBP and p300 coactivators in glial cells of the central and peripheral nervous system, namely in primary cultures of astrocytes and in Schwann cells. We show that both coregulators behave differently in either cell type. CBP enhances GR transcriptional activation in astrocytes, and has no effect in Schwann cells, whereas p300 exerts an inhibitory effect in both glial cells. Studies with p300 deletion mutants show that the repressive capacity of p300 is related to its acetyltransferase activity. This work shows striking differences between CBP and p300 actions in astrocytes. Moreover, in astrocytes the opposite effects of CBP and p300 could lead to a balance in the transactivation potency of the GR, in order to fine tune the action of glucocorticoids.
Collapse
Affiliation(s)
- Cosima Fonte
- INSERM UMR788, University Paris-Sud (Paris XI), 80 rue du Général Leclerc, 94276 Le Kremlin-Bicêtre Cedex, France
| | | | | | | | | |
Collapse
|
160
|
Yang Y, Wolf LV, Cvekl A. Distinct embryonic expression and localization of CBP and p300 histone acetyltransferases at the mouse alphaA-crystallin locus in lens. J Mol Biol 2007; 369:917-26. [PMID: 17467007 PMCID: PMC2063435 DOI: 10.1016/j.jmb.2007.04.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2007] [Revised: 03/26/2007] [Accepted: 04/02/2007] [Indexed: 10/23/2022]
Abstract
Mouse alphaA-crystallin gene encodes the most abundant protein of the mammalian lens. Expression of alphaA-crystallin is regulated temporally and spatially during lens development with initial expression in the lens vesicle followed by strong upregulation in the differentiating primary lens fibers. Lens-specific expression of alphaA-crystallin is mediated by DNA-binding transcription factors Pax6, c-Maf and CREB bound to its promoter region. Its 5'-distal enhancer, DCR1, mediates regulation of alphaA-crystallin via FGF signaling, while its 3'-distal enhancer, DCR3, functions only in elongated primary lens fibers via other lens differentiation pathways. DCR1 and DCR3 establish outside borders of a lens-specific chromatin region marked by histone H3 K9 acetylation. Here, we identified CREB-binding protein (CBP) and p300 as major histone acetyltransferases (HATs) associated in vivo with the mouse alphaA-crystallin locus. Both HATs are expressed in embryonic lens. Expression of CBP in primary lens fiber cells coincides with alphaA-crystallin. In the chromatin of lens epithelial cells, chromatin immunoprecipitations (ChIPs) show that the alphaA-crystallin promoter is notably devoid of any significant presence of CBP and p300, though DCR1 and a few other regions show the presence of these HATs. In the chromatin obtained from newborn lens, CBP was localized specifically at the promoter region with about ten times higher abundance compared to the entire alphaA-crystallin locus. In contrast, p300 is distributed more evenly across the entire locus. Analysis of total histone H3 and H3 K9 acetylation revealed potential lower density of nucleosomes 2 kb upstream from the promoter region. Collectively, our data suggest that moderate level of alphaA-crystallin gene expression in lens epithelial cells does not require the presence of CBP and p300 in the promoter. However, the lens-specific chromatin domain contains both promoter localized CBP on the "background" of locus-spread presence of CBP and p300.
Collapse
Affiliation(s)
- Ying Yang
- Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY10461, USA
| | | | | |
Collapse
|
161
|
Bartholdi D, Roelfsema JH, Papadia F, Breuning MH, Niedrist D, Hennekam RC, Schinzel A, Peters DJM. Genetic heterogeneity in Rubinstein-Taybi syndrome: delineation of the phenotype of the first patients carrying mutations in EP300. J Med Genet 2007; 44:327-33. [PMID: 17220215 PMCID: PMC2597984 DOI: 10.1136/jmg.2006.046698] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Rubinstein-Taybi syndrome (RSTS) is a congenital disorder characterised by growth retardation, facial dysmorphisms, skeletal abnormalities and mental retardation. Broad thumbs and halluces are the hallmarks of the syndrome. RSTS is associated with chromosomal rearrangements and mutations in the CREB-binding protein gene (CREBBP), also termed CBP, encoding the CREB-binding protein. Recently, it was shown that mutations in EP300, coding for the p300 protein, also cause RSTS. CBP and EP300 are highly homologous genes, which play important roles as global transcriptional coactivators. OBJECTIVE To report the phenotype of the presently known patients with RSTS (n = 4) carrying germline mutations of EP300. RESULTS The patients with EP300 mutations displayed the typical facial gestalt and malformation pattern compatible with the diagnosis of RSTS. However, three patients exhibited much milder skeletal findings on the hands and feet than typically observed in patients with RSTS. CONCLUSIONS Part of the clinical variability in RSTS is explained by genetic heterogeneity. The diagnosis of RSTS must be expanded to include patients without broad thumbs or halluces.
Collapse
|
162
|
Riz I, Akimov SS, Eaker SS, Baxter KK, Lee HJ, Mariño-Ramírez L, Landsman D, Hawley TS, Hawley RG. TLX1/HOX11-induced hematopoietic differentiation blockade. Oncogene 2007; 26:4115-23. [PMID: 17213805 PMCID: PMC1955382 DOI: 10.1038/sj.onc.1210185] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Aberrant expression of the human homeobox-containing proto-oncogene TLX1/HOX11 inhibits hematopoietic differentiation programs in a number of murine model systems. Here, we report the establishment of a murine erythroid progenitor cell line, iEBHX1S-4, developmentally arrested by regulatable TLX1 expression. Extinction of TLX1 expression released the iEBHX1S-4 differentiation block, allowing erythropoietin-dependent acquisition of erythroid markers and hemoglobin synthesis. Coordinated activation of erythroid transcriptional networks integrated by the acetyltransferase co-activator CREB-binding protein (CBP) was suggested by bioinformatic analysis of the upstream regulatory regions of several conditionally induced iEBHX1S-4 gene sets. In accord with this notion, CBP-associated acetylation of GATA-1, an essential regulator of erythroid differentiation, increased concomitantly with TLX1 downregulation. Coimmunoprecipitation experiments and glutathione-S-transferase pull-down assays revealed that TLX1 directly binds to CBP, and confocal laser microscopy demonstrated that the two proteins partially colocalize at intranuclear sites in iEBHX1S-4 cells. Notably, the distribution of CBP in conditionally blocked iEBHX1S-4 cells partially overlapped with chromatin marked by a repressive histone methylation pattern, and downregulation of TLX1 coincided with exit of CBP from these heterochromatic regions. Thus, we propose that TLX1-mediated differentiation arrest may be achieved in part through a mechanism that involves redirection of CBP and/or its sequestration in repressive chromatin domains.
Collapse
Affiliation(s)
- I Riz
- Department of Anatomy and Cell Biology, The George Washington University Medical Center, Washington, DC, USA
| | - SS Akimov
- Department of Anatomy and Cell Biology, The George Washington University Medical Center, Washington, DC, USA
| | - SS Eaker
- NanoDetection Technology, Knoxville, TN, USA
| | - KK Baxter
- Department of Anatomy and Cell Biology, The George Washington University Medical Center, Washington, DC, USA
- Molecular Medicine Program, The George Washington University Medical Center, Washington, DC, USA
| | - HJ Lee
- Department of Anatomy and Cell Biology, The George Washington University Medical Center, Washington, DC, USA
- Genomics and Bioinformatics Program, The George Washington University Medical Center, Washington, DC, USA
| | - L Mariño-Ramírez
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, USA
| | - D Landsman
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, USA
| | - TS Hawley
- Flow Cytometry Core Facility, The George Washington University Medical Center, Washington, DC, USA
| | - RG Hawley
- Department of Anatomy and Cell Biology, The George Washington University Medical Center, Washington, DC, USA
- Molecular Medicine Program, The George Washington University Medical Center, Washington, DC, USA
| |
Collapse
|
163
|
Sammons M, Wan SS, Vogel NL, Mientjes EJ, Grosveld G, Ashburner BP. Negative regulation of the RelA/p65 transactivation function by the product of the DEK proto-oncogene. J Biol Chem 2006; 281:26802-12. [PMID: 16829531 DOI: 10.1074/jbc.m600915200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
NF-kappaB-mediated transcriptional activation is controlled at several levels including interaction with coregulatory proteins. To identify new proteins capable of modulating NF-kappaB-mediated activation, a cytoplasmic two-hybrid screen was performed using the p65 C-terminal transactivation domain as bait and identified the product of the DEK proto-oncogene. DEK is a ubiquitous nuclear protein that has been implicated in several types of cancer and autoimmune diseases. DEK appears to function in several nuclear processes including transcriptional repression and modulation of chromatin structure. Our data indicate that DEK functions as a transcriptional corepressor to repress NF-kappaB activity. DEK expression blocked p65-mediated activation of an NF-kappaB-dependent reporter gene and also inhibited TNFalpha-induced activation of the reporter gene. Chromatin Immunoprecipitation (ChIP) assays showed that DEK associates with the promoters of the NF-kappaB-regulated cIAP2 and IL-8 genes in untreated cells and dissociates from these promoters upon NF-kappaB binding in response to TNFalpha treatment. Moreover, the expression levels of an NF-kappaB-dependent reporter gene as well as the NF-kappaB-regulated Mcp-1 and IkappaBalpha genes is increased in DEK-/- cells compared with wild-type cells. ChIP assays on these promoters show enhanced and prolonged binding of p65 and increased recruitment of the P/CAF coactivator. Overall, these data provide further evidence that DEK functions to negatively regulate transcription.
Collapse
Affiliation(s)
- Morgan Sammons
- Department of Biological Sciences and Undergraduate Honors Program, University of Toledo, Toledo, Ohio 43606, and Department of Genetics and Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
| | | | | | | | | | | |
Collapse
|
164
|
Xu W, Fukuyama T, Ney PA, Wang D, Rehg J, Boyd K, van Deursen JMA, Brindle PK. Global transcriptional coactivators CREB-binding protein and p300 are highly essential collectively but not individually in peripheral B cells. Blood 2006; 107:4407-16. [PMID: 16424387 PMCID: PMC1895794 DOI: 10.1182/blood-2005-08-3263] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
CREB-binding protein (CBP) and its para-log p300 are transcriptional coactivators that physically or functionally interact with over 320 mammalian and viral proteins, including 36 that are essential for B cells in mice. CBP and p300 are generally considered limiting for transcription, yet their roles in adult cell lineages are largely unknown since homozygous null mutations in either gene or compound heterozygosity cause early embryonic lethality in mice. We tested the hypotheses that CBP and p300 are limiting and that each has unique properties in B cells, by using mice with Cre/LoxP conditional knockout alleles for CBP (CBP(flox)) and p300 (p300(flox)), which carry CD19(Cre) that initiates floxed gene recombination at the pro-B-cell stage. CD19(Cre)-mediated loss of CBP or p300 led to surprisingly modest deficits in B-cell numbers, whereas inactivation of both genes was not tolerated by peripheral B cells. There was a moderate decrease in B-cell receptor (BCR)-responsive gene expression in CBP or p300 homozygous null B cells, suggesting that CBP and p300 are essential for this signaling pathway that is crucial for B-cell homeostasis. These results indicate that individually CBP and p300 are partially limiting beyond the pro-B-cell stage and that other coactivators in B cells cannot replace their combined loss.
Collapse
Affiliation(s)
- Wu Xu
- Department of Biochemistry, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | | | | | | | | | | | | | | |
Collapse
|
165
|
Nuclear receptor transcriptional coactivators in development and metabolism. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/s1574-3349(06)16012-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
166
|
Oliveira AMM, Abel T, Brindle PK, Wood MA. Differential role for CBP and p300 CREB-binding domain in motor skill learning. Behav Neurosci 2006; 120:724-9. [PMID: 16768624 DOI: 10.1037/0735-7044.120.3.724] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cyclic adenosine monophosphate response element binding protein (CREB) binding protein (CBP) and E1A binding protein (p300) are highly homologous transcriptional coactivators with histone acetyltransferase activity. Although CBP and p300 have unique functions in vivo during embryogenesis and hematopoiesis, their functions within the nervous system remain poorly understood. The authors demonstrate that these coactivators have differential roles in motor skill learning. Mice with a mutation in the CREB-binding (KIX) domain of CBP exhibited motor learning deficits. However, mice with the analogous mutation in the KIX domain of p300 showed normal motor learning. Further, CREB knock-out mice exhibited a motor learning deficit similar to that of CBP-KIX mutant mice. These results suggest that the CREB-CBP interaction is more limiting or critical than the CREB-p300 interaction for motor skill learning. Thus, CBP and p300 are genetically distinct at the behavioral level.
Collapse
Affiliation(s)
- Ana M M Oliveira
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | | |
Collapse
|