Genomes and Genes
Function and Mechanism of CUL4 E3 Ligases in Human Diseases
Principal Investigator: Yue Xiong
Abstract: DESCRIPTION (provided by applicant): Most, if not all, cellular processes are regulated by timely degradation of regulatory proteins through the ubiquitin system. Specific substrate proteins are targeted for degradation through the activity of E3 ubiquitin ligases. We previously discovered that two small RING finger proteins, ROC1 and ROC2, function as the essential catalytic components of the largest family of E3 ligase complexes, the cullin-RING E3 ligases (CRLs). We also discovered that cullin 3 and cullin 4 could assemble as many as 200 and 100 distinct CRL3 and CRL4 E3 complexes, respectively. In this application, we propose two lines of research aimed at understanding the function and mechanism of two specific CRL4 E3 ubiquitin ligase complexes, CRL4G[unreadable]2, and CRL4WDR5, and how alterations of these CRL4 complexes contribute to two major human diseases, heart failure and X-linked mental retardation. In the first Aim, we will examine the molecular function of CRL4 G[unreadable]2 and its role in cardiovascular disease. We present data demonstrating that a WD40 protein, G-protein [unreadable] subunit 2 (G[unreadable]2), associates with DDB1- CUL4A to target G protein-coupled receptor kinases (GRK2), for ubiquitylation. Elevated GRK2 has previously been associated with myocardial infarction, heart failure, portal hypertension, insulin resistance, and Alzheimer's disease. We propose first to explore how broadly CRL4 is involved in the regulation of G- protein coupled receptor (GPCR) signaling by determining the interaction of CRL4 with other G[unreadable] and GRK proteins. We will then focus on one well-characterized GPCR signaling pathway, [unreadable]-adrenergic receptors ([unreadable] - AR) signaling, to determine the mechanism of CRL4G[unreadable]2 mediated GRK2 ubiquitylation. We will also determine whether loss of Cul4a impairs heart function in mouse. In the second Aim, we present data demonstrating that CUL4B, one of the most frequently mutated genes in X-linked mental retardation (XLMR) patients, but not CUL4A, is a nuclear E3 ligase of WDR5, a WD40 protein and an essential component for histone H3K4 trimethylation. We propose to determine the function of CUL4B-mediated WDR5 ubiquitylation in neuronal cell proliferation, survival and differentiation. We also propose to develop and characterize a novel mouse model, conditional Cul4b mutant mouse strain, to determine the function of Cul4b in brain. Finally, we propose to determine broadly the function of CUL4B in the regulation of chromatin modification and gene expression.
Funding Period: 2003-02-01 - 2015-03-31
more information: NIH RePORT
- An evolutionarily conserved function of proliferating cell nuclear antigen for Cdt1 degradation by the Cul4-Ddb1 ubiquitin ligase in response to DNA damageJian Hu
Department of Biochemistry and Biophysics, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, 27516 7295, USA
J Biol Chem 281:3753-6. 2006....
- VprBP binds full-length RAG1 and is required for B-cell development and V(D)J recombination fidelityMichele D Kassmeier
Department of Medical Microbiology and Immunology, Creighton University Medical Center, Omaha, NE, USA
EMBO J 31:945-58. 2012..These data suggest full-length RAG1 recruits a cullin RING E3 ligase complex to ubiquitylate an unknown protein(s) to limit error-prone repair during V(D)J recombination...
- X-linked mental retardation gene CUL4B targets ubiquitylation of H3K4 methyltransferase component WDR5 and regulates neuronal gene expressionTadashi Nakagawa
Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
Mol Cell 43:381-91. 2011..Our results identify WDR5 as a critical substrate of CUL4B in regulating neuronal gene expression and suggest epigenetic change as a common pathogenic mechanism for CUL4B-associated XLMR...
- Cytoplasmic CUL9/PARC ubiquitin ligase is a tumor suppressor and promotes p53-dependent apoptosisXin Hai Pei
Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599 7295, USA
Cancer Res 71:2969-77. 2011..Ectopic expression of wild-type CUL9, but not a point mutant CUL9 deficient in p53 binding, promotes apoptosis. These results show CUL9 as a potential p53-activating E3 ligase in the cytoplasm...
- PP1 cooperates with ASPP2 to dephosphorylate and activate TAZChen Ying Liu
Key Laboratory of Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology School of Medicine, Lab, Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
J Biol Chem 286:5558-66. 2011..As a result, PP1 and ASPP2 increase TAZ-dependent gene expression. This study demonstrates that PP1A and ASPP2 play a critical role in promoting TAZ function by antagonizing the LATS kinase through TAZ dephosphorylation...
- Targeted ubiquitylation: the prey becomes predatorJun Yan
Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 7295, USA
Mol Cell 40:853-5. 2010..2010) demonstrate that the yeast transcription factor Met4, a target of the SCF(Met30) E3 ligase for nonproteolytic polyubiquitylation, can also function to target its cofactors for proteolytic ubiquitylation by the same E3 ligase...
- Cell type-dependent requirement for PIP box-regulated Cdt1 destruction during S phaseHyun O Lee
Curriculum in Genetics and Molecular Biology, Department of Biochemistry and Biophysics, Lineberger Comprehensive Cancer Center, and Program in Molecular Biology and Biotechnology, University of North Carolina, Chapel Hill, NC 27599, USA
Mol Biol Cell 21:3639-53. 2010..These data indicate that PIP box-mediated destruction of Dup is necessary for the cell division cycle and suggest that Geminin inhibition can restrain Dup(ΔPIP) activity in some endocycling cell types...
- CRL4s: the CUL4-RING E3 ubiquitin ligasesSarah Jackson
Department of Biochemistry and Biophysics, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, NC 27599, USA
Trends Biochem Sci 34:562-70. 2009..Many CRL4 complexes are involved in chromatin regulation and are frequently hijacked by different viruses...
- DDB1-CUL4 and MLL1 mediate oncogene-induced p16INK4a activationYojiro Kotake
Lineberger Comprehensive Cancer Center and Department of Biochemistry and Biophysics, Program in Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 7295, USA
Cancer Res 69:1809-14. 2009....
- Ectromelia virus encodes a novel family of F-box proteins that interact with the SCF complexNick van Buuren
621 HMRC, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
J Virol 82:9917-27. 2008..Our results indicate that ectromelia virus has evolved multiple proteins that interact with the SCF complex...
- Human immunodeficiency virus type 1 Vpr-binding protein VprBP, a WD40 protein associated with the DDB1-CUL4 E3 ubiquitin ligase, is essential for DNA replication and embryonic developmentChad M McCall
Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
Mol Cell Biol 28:5621-33. 2008..Our studies identify a previously unknown function of VprBP in S-phase progression and suggest the possibility that HIV-1 Vpr may divert an ongoing chromosomal replication activity to facilitate viral replication...
- WD40 protein FBW5 promotes ubiquitination of tumor suppressor TSC2 by DDB1-CUL4-ROC1 ligaseJian Hu
Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
Genes Dev 22:866-71. 2008..These results indicate that FBW5-DDB1-CUL4-ROC1 is an E3 ubiquitin ligase regulating TSC2 protein stability and TSC complex turnover...
- Ectromelia virus BTB/kelch proteins, EVM150 and EVM167, interact with cullin-3-based ubiquitin ligasesBrianne A Wilton
Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
Virology 374:82-99. 2008..Our findings suggest that the ectromelia virus-encoded BTB/kelch proteins, EVM150 and EVM167, interact with cullin-3 potentially functioning to recruit unidentified substrates for ubiquitination...
- DDB1 functions as a linker to recruit receptor WD40 proteins to CUL4-ROC1 ubiquitin ligasesYizhou Joseph He
Lineberger Comprehensive Cancer Center, Department of Biochemistry and Biophysics, Program in Molecular Biology and Biotechnology, University of North Carolina, Chapel Hill, NC 27599, USA
Genes Dev 20:2949-54. 2006..A database search predicts that about one-third of WD40 proteins, 90 in humans, contain the DWD box, suggesting a potentially large number of DWD-DDB1-CUL4-ROC1 E3 ligases...
- Vpr-binding protein antagonizes p53-mediated transcription via direct interaction with H3 tailKyunghwan Kim
Department of Biochemistry and Molecular Biology, Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, California, USA
Mol Cell Biol 32:783-96. 2012..Our results thus reveal a new role for VprBP in regulation of the p53 signaling pathway, as well as molecular mechanisms of cancer development related to VprBP misregulation...
- Rest-Activated Program of Gene Expression in IschemiaR Suzanne Zukin; Fiscal Year: 2013....
- Repression via Facultative Heterochomatin.DANNY F REINBERG; Fiscal Year: 2013..The aim of this proposal is to better understand the molecular mechanisms involved in this process, and their role in disease such as cancer. ..
- Role of Ubiquitin in Cardiovascular SystemSong Li; Fiscal Year: 2013..1 ..
- HORMONAL REGULATION OF BLOOD PRESSUREMichal Laniado Schwartzman; Fiscal Year: 2013..ular tone, in the pathophysiology of hypertension and cardiovascular disease. ..
- Mechanisms of Atherogenesis in Insulin ResistanceIRA A TABAS; Fiscal Year: 2013..End of Abstract) ..