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Yang X, Wu ST, Gao R, Wang R, Wang Y, Dong Z, Wang L, Qi C, Wang X, Schmitz ML, Liu R, Han Z, Wang L, Zheng X. Release of STK24/25 suppression on MEKK3 signaling in endothelial cells confers cerebral cavernous malformation. JCI Insight 2023; 8:160372. [PMID: 36692953 PMCID: PMC10077477 DOI: 10.1172/jci.insight.160372] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 01/20/2023] [Indexed: 01/25/2023] Open
Abstract
Loss-of-function mutations in cerebral cavernous malformation (CCM) genes and gain-of-function mutation in the MAP3K3 gene encoding MEKK3 cause CCM. Deficiency of CCM proteins leads to the activation of MEKK3-KLF2/4 signaling, but it is not clear how this occurs. Here, we demonstrate that deletion of the CCM3 interacting kinases STK24/25 in endothelial cells causes defects in vascular patterning during development as well as CCM lesion formation during postnatal life. While permanent deletion of STK24/25 in endothelial cells caused developmental defects of the vascular system, inducible postnatal deletion of STK24/25 impaired angiogenesis in the retina and brain. More importantly, deletion of STK24/25 in neonatal mice led to the development of severe CCM lesions. At the molecular level, a hybrid protein consisting of the STK kinase domain and the MEKK3 interacting domain of CCM2 rescued the vascular phenotype caused by the loss of ccm gene function in zebrafish. Our study suggests that CCM2/3 proteins act as adapters to allow recruitment of STK24/25 to limit the constitutive MEKK3 activity, thus contributing to vessel stability. Loss of STK24/25 causes MEKK3 activation, leading to CCM lesion formation.
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Affiliation(s)
- Xi Yang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
| | - Shi-Ting Wu
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
| | - Rui Gao
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
| | - Rui Wang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
| | - Yixuan Wang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
| | - Zhenkun Dong
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Lu Wang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
| | - Chunxiao Qi
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
| | - Xiaohong Wang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
| | - M Lienhard Schmitz
- Institute of Biochemistry, Justus Liebig University, Member of the German Center for Lung Research, Giessen, Germany
| | - Renjing Liu
- Vascular Epigenetics Laboratory, Victor Chang Cardiac Research Institute, and St. Vincent's Clinical School, University of New South Wales, Sydney, Australia
| | - Zhiming Han
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, and.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Lu Wang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Xiangjian Zheng
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, and Center for Cardiovascular Diseases, Tianjin Medical University, China
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Qu F, Zeng X, Liu Z, Guo M, Zhang X, Cao S, Zhou Y, He Z, Tang J, Mao Z, Yang Y, Zhou Z, Liu Z. Functional characterization of MEKK3 in the intestinal immune response to bacterial challenges in grass carp (Ctenopharyngodon idella). Front Immunol 2022; 13:981995. [PMID: 35990669 PMCID: PMC9388831 DOI: 10.3389/fimmu.2022.981995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
Mitogen-activated protein kinase kinase kinase 3 (MEKK3) is an evolutionarily conserved Ser/Thr protein kinase of the MEKK family that is essential for the host immune response to pathogen challenges in mammals. However, the immune function of MEKK3s in lower vertebrate species, especially in bony fish, remains largely unknown. In this study, a fish MEKK3 (designated CiMEKK3) gene was cloned and identified from grass carp (Ctenopharyngodon idella). The present CiMEKK3 cDNA encoded a 620 amino acid polypeptide containing a conserved S-TKc domain and a typical PB1 domain. Several potential immune-related transcription factor-binding sites, including activating protein 1 (AP-1), nuclear factor kappa B (NF-κB) and signal transducer and activator of downstream transcription 3 (STAT3), were observed in the 5’ upstream DNA sequence of CiMEKK3. A phylogenetic tree showed that CiMEKK3 exhibits a close evolutionary relationship with MEKK3s from Cyprinus carpio and Carassius auratus. Quantitative real-time PCR analysis revealed that CiMEKK3 transcripts were widely distributed in all selected tissues of healthy grass carp, with a relatively high levels observed in the gill, head kidney and intestine. Upon in vitro challenge with bacterial pathogens (Aeromonas hydrophila and Aeromonas veronii) and pathogen-associated molecular patterns (PAMPs) (lipopolysaccharide (LPS), peptidoglycan (PGN), L-Ala-γ-D-Glu-mDAP (Tri-DAP) and muramyl dipeptide (MDP)), the expression levels of CiMEKK3 in the intestinal cells of grass carp were shown to be significantly upregulated in a time-dependent manner. In vivo injection experiments revealed that CiMEKK3 transcripts were significantly induced by MDP challenge in the intestine; however, these effects could be inhibited by the nutritional dipeptides carnosine and Ala-Gln. Moreover, subcellular localization analysis and luciferase reporter assays indicated that CiMEKK3 could act as a cytoplasmic signal-transducing activator involved in the regulation of NF-κB and MAPK/AP-1 signaling cascades in HEK293T cells. Taken together, these findings strongly suggest that CiMEKK3 plays vital roles in the intestinal immune response to bacterial challenges, which will aid in understanding the pathogenesis of inflammatory bowel disease in bony fish.
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Affiliation(s)
- Fufa Qu
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Xuan Zeng
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Zhenzhen Liu
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Meixing Guo
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Xia Zhang
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Shenping Cao
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Yonghua Zhou
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Zhimin He
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Jianzhou Tang
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Zhuangwen Mao
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
| | - Yalin Yang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhigang Zhou
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhen Liu
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, China
- *Correspondence: Zhen Liu,
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Enchéry F, Dumont C, Iampietro M, Pelissier R, Aurine N, Bloyet LM, Carbonnelle C, Mathieu C, Journo C, Gerlier D, Horvat B. Nipah virus W protein harnesses nuclear 14-3-3 to inhibit NF-κB-induced proinflammatory response. Commun Biol 2021; 4:1292. [PMID: 34785771 PMCID: PMC8595879 DOI: 10.1038/s42003-021-02797-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/08/2021] [Indexed: 12/15/2022] Open
Abstract
Nipah virus (NiV) is a highly pathogenic emerging bat-borne Henipavirus that has caused numerous outbreaks with public health concerns. It is able to inhibit the host innate immune response. Since the NF-κB pathway plays a crucial role in the innate antiviral response as a major transcriptional regulator of inflammation, we postulated its implication in the still poorly understood NiV immunopathogenesis. We report here that NiV inhibits the canonical NF-κB pathway via its nonstructural W protein. Translocation of the W protein into the nucleus causes nuclear accumulation of the cellular scaffold protein 14-3-3 in both African green monkey and human cells infected by NiV. Excess of 14-3-3 in the nucleus was associated with a reduction of NF-κB p65 subunit phosphorylation and of its nuclear accumulation. Importantly, W-S449A substitution impairs the binding of the W protein to 14-3-3 and the subsequent suppression of NF-κB signaling, thus restoring the production of proinflammatory cytokines. Our data suggest that the W protein increases the steady-state level of 14-3-3 in the nucleus and consequently enhances 14-3-3-mediated negative feedback on the NF-κB pathway. These findings provide a mechanistic model of W-mediated disruption of the host inflammatory response, which could contribute to the high severity of NiV infection.
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Affiliation(s)
- François Enchéry
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Claire Dumont
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Mathieu Iampietro
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Rodolphe Pelissier
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Noémie Aurine
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Louis-Marie Bloyet
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Caroline Carbonnelle
- INSERM- Laboratoire P4 Jean Mérieux, 21 Avenue Tony Garnier, 69365, Lyon, France
| | - Cyrille Mathieu
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Chloé Journo
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Denis Gerlier
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France
| | - Branka Horvat
- CIRI, Centre International de Recherche en Infectiologie, Inserm U1111, CNRS, UMR5308, Univ Lyon, Université Claude Bernard Lyon 1, École Normale Supérieure de Lyon, Lyon, France.
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4
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Li D, Kong L, Cui Z, Zhao F, Deng Y, Tan A, Jiang L. MEKK3 in hybrid snakehead (Channa maculate ♀ ×Channa argus ♂): Molecular characterization and immune response to infection with Nocardia seriolae and Aeromonas schubertii. Comp Biochem Physiol B Biochem Mol Biol 2021; 256:110643. [PMID: 34186154 DOI: 10.1016/j.cbpb.2021.110643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 06/19/2021] [Accepted: 06/25/2021] [Indexed: 12/30/2022]
Abstract
Mitogen-activated protein kinase/extracellular signal-regulated kinase kinase kinase 3 (MEKK3) is a serine/threonine protein kinase that acts as a key regulator and is widely involved in various innate and acquired immune signaling pathways. In this study, we first cloned the complete open reading frame (ORF) of the MEKK3 gene (named CcMEKK3) in a hybrid snakehead (Channa maculate ♀ × Channa argus ♂). The full-length ORF of CcMEKK3 is 1851 bp, and encodes a putative protein of 616 amino acids containing a serine/threonine kinase catalytic (S-TKc) domain and a Phox and Bem1p (PB1) domain. A sequence alignment and phylogenetic tree analysis showed that CcMEKK3 is highly conserved relative to the MEKK3 proteins of other teleost species. CcMEKK3 was constitutively expressed in all the healthy hybrid snakehead tissues tested, with greatest expression in the immune tissues, such as the head kidney and spleen. The expression of CcMEKK3 was usually upregulated in the head kidney, spleen, and liver at different time points after infection with Nocardia seriolae or Aeromonas schubertii. Similarly, the dynamic expression levels of CcMEKK3 in head kidney leukocytes after stimulation revealed that CcMEKK3 was induced by LTA, LPS, and poly(I:C). In the subcellular localization analysis, CcMEKK3 was evenly distributed in the cytoplasm of HEK293T cells, and its overexpression significantly promoted the activities of NF-κB and AP-1. These results suggest that CcMEKK3 is involved in the immune defense against these two pathogens, and plays a crucial role in activating the NF-κB and MAPK signaling pathways.
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Affiliation(s)
- Dongqi Li
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong 510380, China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Lulu Kong
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong 510380, China
| | - Zhengwei Cui
- Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Fei Zhao
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong 510380, China.
| | - Yuting Deng
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong 510380, China
| | - Aiping Tan
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong 510380, China
| | - Lan Jiang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong 510380, China
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5
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Munier CC, Ottmann C, Perry MWD. 14-3-3 modulation of the inflammatory response. Pharmacol Res 2020; 163:105236. [PMID: 33053447 DOI: 10.1016/j.phrs.2020.105236] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 10/02/2020] [Accepted: 10/04/2020] [Indexed: 01/11/2023]
Abstract
Regulation of inflammation is a central part of the maintenance of homeostasis by the immune system. One important class of regulatory protein that has been shown to have effects on the inflammatory process are the 14-3-3 proteins. Herein we describe the roles that have been identified for 14-3-3 in regulation of the inflammatory response. These roles encompass regulation of the response that affect inflammation at the genetic, molecular and cellular levels. At a genetic level 14-3-3 is involved in the regulation of multiple transcription factors and affects the transcription of key effectors of the immune response. At a molecular level many of the constituent parts of the inflammatory process, such as pattern recognition receptors, protease activated receptors and cytokines are regulated through phosphorylation and recognition by 14-3-3 whilst disruption of the recognition processes has been observed to result in clinical syndromes. 14-3-3 is also involved in the regulation of cell proliferation and differentiation, this has been shown to affect the immune system, particularly T- and B-cells. Finally, we discuss how abnormal levels of 14-3-3 contribute to undesirable immune responses and chronic inflammatory conditions.
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Affiliation(s)
- Claire C Munier
- Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden; Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Technische Universiteit Eindhoven, Den Dolech 2, 5612 AZ Eindhoven, the Netherlands
| | - Christian Ottmann
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Technische Universiteit Eindhoven, Den Dolech 2, 5612 AZ Eindhoven, the Netherlands
| | - Matthew W D Perry
- Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden.
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Mao X, Phanavanh B, Hamdan H, Moerman-Herzog A, Barger SW. NFκB-inducing kinase inhibits NFκB activity specifically in neurons of the CNS. J Neurochem 2016; 137:154-63. [PMID: 26778773 PMCID: PMC5115916 DOI: 10.1111/jnc.13526] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 12/15/2015] [Accepted: 01/04/2016] [Indexed: 12/30/2022]
Abstract
The control of NFκB in CNS neurons appears to differ from that in other cell types. Studies have reported induction of NFκB in neuronal cultures and immunostaining in vivo, but others have consistently detected little or no transcriptional activation by NFκB in brain neurons. To test if neurons lack some component of the signal transduction system for NFκB activation, we transfected cortical neurons with several members of this signaling system along with a luciferase-based NFκB-reporter plasmid; RelA was cotransfected in some conditions. No component of the NFκB pathway was permissive for endogenous NFκB activity, and none stimulated the activity of exogenous RelA. Surprisingly, however, the latter was inhibited by cotransfection of NFκB-inducing kinase (NIK). Fluorescence imaging of RelA indicated that co-expression of NIK sequestered RelA in the cytoplasm, similar to the effect of IκBα. NIK-knockout mice showed elevated expression of an NFκB-reporter construct in neurons in vivo. Cortical neurons cultured from NIK-knockout mice showed elevated expression of an NFκB-reporter transgene. Consistent with data from other cell types, a C-terminal fragment of NIK suppressed RelA activity in astrocytes as well as neurons. Therefore, the inhibitory ability of the NIK C-terminus was unbiased with regard to cell type. However, inhibition of NFκB by full-length NIK is a novel outcome that appears to be specific to CNS neurons. This has implications for unique aspects of transcription in the CNS, perhaps relevant to aspects of development, neuroplasticity, and neuroinflammation. Full-length NIK was found to inhibit (down arrow) transcriptional activation of NFκB in neurons, while it elevated (up arrow) activity in astrocytes. Deletion constructs corresponding to the N-terminus or C-terminus also inhibited NFκB in neurons, while only the C-terminus did so in astrocytes. One possible explanation is that the inhibition in neurons occurs via two different mechanisms, including the potential for a neuron-specific protein (e.g., one of the 14-3-3 class) to create a novel complex in neurons, whereas the C-terminus may interact directly with NFκB. [Structure of NIK is based on Liu J., Sudom A., Min X., Cao Z., Gao X., Ayres M., Lee F., Cao P., Johnstone S., Plotnikova O., Walker N., Chen G., and Wang Z. (2012) Structure of the nuclear factor κB-inducing kinase (NIK) kinase domain reveals a constitutively active conformation. J Biol Chem. 287, 27326-27334); N-terminal lobe is oriented at top].
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Affiliation(s)
- Xianrong Mao
- Department of Genetics, Washington University, St. Louis MO 63110
| | - Bounleut Phanavanh
- Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock AR 72205
| | - Hamdan Hamdan
- Department of Neuroscience, Baylor College of Medicine, Houston TX 77030
| | - Andréa Moerman-Herzog
- Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock AR 72205
| | - Steven W. Barger
- Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock AR 72205
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock AR 72205
- Geriatric Research Education and Clinical Center, Central Arkansas Veterans Healthcare System, Little Rock AR 72205
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The cerebral cavernous malformation proteins CCM2L and CCM2 prevent the activation of the MAP kinase MEKK3. Proc Natl Acad Sci U S A 2015; 112:14284-9. [PMID: 26540726 DOI: 10.1073/pnas.1510495112] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Three genes, CCM1, CCM2, and CCM3, interact genetically and biochemically and are mutated in cerebral cavernous malformations (CCM). A recently described member of this CCM family of proteins, CCM2-like (CCM2L), has high homology to CCM2. Here we show that its relative expression in different tissues differs from that of CCM2 and, unlike CCM2, the expression of CCM2L in endothelial cells is regulated by density, flow, and statins. In vitro, both CCM2L and CCM2 bind MEKK3 in a complex with CCM1. Both CCM2L and CCM2 interfere with MEKK3 activation and its ability to phosphorylate MEK5, a downstream target. The in vivo relevance of this regulation was investigated in zebrafish. A knockdown of ccm2l and ccm2 in zebrafish leads to a more severe "big heart" and circulation defects compared with loss of function of ccm2 alone, and also leads to substantial body axis abnormalities. Silencing of mekk3 rescues the big heart and body axis phenotype, suggesting cross-talk between the CCM proteins and MEKK3 in vivo. In endothelial cells, CCM2 deletion leads to activation of ERK5 and a transcriptional program that are downstream of MEKK3. These findings suggest that CCM2L and CCM2 cooperate to regulate the activity of MEKK3.
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MEKK3 and TAK1 synergize to activate IKK complex in Helicobacter pylori infection. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:715-24. [PMID: 24418622 DOI: 10.1016/j.bbamcr.2014.01.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Revised: 01/03/2014] [Accepted: 01/05/2014] [Indexed: 02/07/2023]
Abstract
Helicobacter pylori colonises the gastric epithelial cells of half of the world's population and represents a risk factor for gastric adenocarcinoma. In gastric epithelial cells H. pylori induces the immediate early response transcription factor nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF-κB) and the innate immune response. We show that H. pylori induces in a type IV secretion system-dependent (T4SS) and cytotoxin associated gene A protein (CagA)-independent manner a transient activation of the inhibitor of NF-κB (IκBα) kinase (IKK)-complex. IKKα and IKKβ expression stabilises the regulatory IKK complex subunit NF-κB essential modulator (NEMO). We provide evidence for an intimate mutual control of the IKK complex by mitogen-activated protein kinase kinase kinase 3 (MEKK3) and transforming growth factor β activated kinase 1 (TAK1). TAK1 interacts transiently with the E3 ubiquitin ligase tumor necrosis factor receptor-associated factor 6 (TRAF6). Protein modifications in the TAK1 molecule, e.g. TAK1 autophosphorylation and K63-linked ubiquitinylation, administer NF-κB signalling including transient recruitment of the IKK-complex. Overall, our data uncover H. pylori-induced interactions and protein modifications of the IKK complex, and its upstream regulatory factors involved in NF-κB activation.
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9
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Matitau AE, Gabor TV, Gill RM, Scheid MP. MEKK2 kinase association with 14-3-3 protein regulates activation of c-Jun N-terminal kinase. J Biol Chem 2013; 288:28293-302. [PMID: 23963453 DOI: 10.1074/jbc.m113.511352] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
MEKK2 (MAP/ERK kinase kinase-2) is a serine/threonine kinase that belongs to the MEKK/STE11 family of MAP kinase kinase kinases (MAP(3)Ks). MEKK2 integrates stress and mitogenic signals to the activation of NF-κB, JNK1/2, p38, and ERK5 pathways. We have found that MEKK2 is regulated through a phosphorylation-dependent association with 14-3-3, a group of adapters that modulate dimerization and association between proteins. We found that MEKK2 was phosphorylated at Thr-283, which resulted in decreased activation loop phosphorylation at Ser-519 and consequently reduced activity. Mechanistically, we found that MEKK2 associated with inactive MEKK2 in the absence of 14-3-3 binding, which led to trans-autophosphorylation of Ser-519. Enforced binding with 14-3-3 reduced Ser-519 trans-autophosphorylation. Expression of T283A MEKK2 within a MEKK2(-/-) background enhanced stress-activated c-Jun N-terminal kinase activity while elevating IL-6 expression, but also reduced ERK activation with a corresponding reduced proliferation rate. These results indicate that Thr-283 phosphorylation is an important regulatory mechanism for MEKK2 activation.
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Affiliation(s)
- Adi E Matitau
- From the Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
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10
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The MYC-associated protein CDCA7 is phosphorylated by AKT to regulate MYC-dependent apoptosis and transformation. Mol Cell Biol 2012; 33:498-513. [PMID: 23166294 DOI: 10.1128/mcb.00276-12] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cell division control protein A7 (CDCA7) is a recently identified target of MYC-dependent transcriptional regulation. We have discovered that CDCA7 associates with MYC and that this association is modulated in a phosphorylation-dependent manner. The prosurvival kinase AKT phosphorylates CDCA7 at threonine 163, promoting binding to 14-3-3, dissociation from MYC, and sequestration to the cytoplasm. Upon serum withdrawal, induction of CDCA7 expression in the presence of MYC sensitized cells to apoptosis, whereas CDCA7 knockdown reduced MYC-dependent apoptosis. The transformation of fibroblasts by MYC was reduced by coexpression of CDCA7, while the non-MYC-interacting protein Δ(156-187)-CDCA7 largely inhibited MYC-induced transformation. These studies provide insight into a new mechanism by which AKT signaling to CDCA7 could alter MYC-dependent growth and transformation, contributing to tumorigenesis.
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Schuster TB, Costina V, Findeisen P, Neumaier M, Ahmad-Nejad P. Identification and functional characterization of 14-3-3 in TLR2 signaling. J Proteome Res 2011; 10:4661-70. [PMID: 21827211 DOI: 10.1021/pr200461p] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The Interleukin-1/Toll-like receptor signaling pathway is a crucial signaling pathway within the innate immune system and the use of mass spectrometric techniques became valuable to investigate signal transduction pathways. To date only a few reports exist that focus on the mass spectrometric identification of novel signaling intermediates within the TLR signal transduction pathway. Here we used this approach systematically to identify new interaction partners of the TLR signaling pathway and subsequently characterized them functionally. We identified 14-3-3 theta as a new member of the TLR signaling complex. With genetic complementation assays, we demonstrate that 14-3-3 negatively regulates TLR2-dependent NF-κB activity and amplifies the TLR4-dependent activation of the transcription factor. While 14-3-3 has no effect on TLR-induced apoptosis in innate immune cells, it controls the release of the inflammatory, IRF3-dependent cytokines like RANTES and IP-10 after stimulation with LPS. Most strikingly, 14-3-3 controls the production of proinflammatory cytokines like IL-6, IL-8, and TNFα in a different manner. Our results identify 14-3-3 theta as a new and important regulatory protein in the TLR signaling suppressing the MyD88-dependent pathway.
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Affiliation(s)
- Tobias B Schuster
- Institute for Clinical Chemistry, Medical Faculty Mannheim, University of Heidelberg , Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
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Samanta AK, Huang HJ, Le XF, Mao W, Lu KH, Bast RC, Liao WSL. MEKK3 expression correlates with nuclear factor kappa B activity and with expression of antiapoptotic genes in serous ovarian carcinoma. Cancer 2009; 115:3897-908. [PMID: 19517469 DOI: 10.1002/cncr.24445] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Constitutively activated nuclear factor kappa B (NFkappaB) contributes to the development of cancer by regulating the expression of genes involved in cell survival, metastasis, and angiogenesis. The authors have demonstrated that MEKK3 plays a critical role in cytokine-mediated NFkappaB activation, and that stable expression of MEKK3 in cultured cells leads to increased NFkappaB activity. METHODS MEKK3 expression in ovarian cancer cells or tumors was assessed by Western blotting and real-time polymerase chain reaction. NFkappaB activities were analyzed by electrophoretic mobility shift assay and luciferase reporter assays. Western blot analysis for the survival factors were also performed and correlated with MEKK3 and NFkappaB activities. Cell survival assays were used to determine the sensitivity of ovarian cancer cells to various chemotherapeutic agents. RESULTS The authors found that 63% of the ovarian cancers had higher MEKK3 expression than the normal ovarian epithelial cells. Ovarian cancers with high MEKK3 showed correspondingly high IkappaB kinase and NFkappaB activity. Moreover, MEKK3 coimmunoprecipitated with Akt and cooperated with Akt to synergistically activate NFkappaB. Consistent with increased MEKK3 and NFkappaB activity in ovarian cancers, Bcl-2, Bcl-xL, survivin, and X-linked inhibitor of apoptosis levels were increased, which correlated with increased resistance to chemotherapeutic agents. Knockdown of MEKK3 with small interfering RNA significantly increased cancer cell sensitivity to paclitaxel. CONCLUSIONS MEKK3 may be aberrantly expressed in ovarian cancers and plays an important role in tumors with constitutively activated NFkappaB.
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Affiliation(s)
- Ajoy K Samanta
- Department of Biochemistry and Molecular Biology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
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Wang X, Zingarelli B, O'Connor M, Zhang P, Adeyemo A, Kranias EG, Wang Y, Fan GC. Overexpression of Hsp20 prevents endotoxin-induced myocardial dysfunction and apoptosis via inhibition of NF-kappaB activation. J Mol Cell Cardiol 2009; 47:382-90. [PMID: 19501592 DOI: 10.1016/j.yjmcc.2009.05.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 05/27/2009] [Accepted: 05/28/2009] [Indexed: 10/20/2022]
Abstract
The occurrence of cardiovascular dysfunction in sepsis is associated with a significantly increased mortality rate of 70% to 90% compared with 20% in septic patients without cardiovascular impairment. Thus, rectification or blockade of myocardial depressant factors should partly ameliorate sepsis progression. Heat shock protein 20 (Hsp20) has been shown to enhance myocardial contractile function and protect against doxorubicin-induced cardiotoxicity. To investigate the possible role of Hsp20 in sepsis-mediated cardiac injury, we first examined the expression profiles of five major Hsps in response to lipopolysaccharide (LPS) challenge, and observed that only the expression of Hsp20 was downregulated in LPS-treated myocardium, suggesting that this decrease might be one of the mechanisms contributing to LPS-induced cardiovascular defects. Further studies using loss-of-function and gain-of-function approaches in adult rat cardiomyocytes verified that reduced Hsp20 levels were indeed correlated with the impaired contractile function. In fact, overexpression of Hsp20 significantly enhanced cardiomyocyte contractility upon LPS treatment. Moreover, after administration of LPS (25 microg/g) in vivo, Hsp20 transgenic mice (10-fold overexpression) displayed: 1) an improvement in myocardial function; 2) reduced the degree of cardiac apoptosis; and 3) decreased NF-kappaB activity, accompanied with reduced myocardial cytokines IL-1beta and TNF-alpha production, compared to the LPS-treated non-transgenic littermate controls. Thus, the increases in Hsp20 levels can protect against LPS-induced cardiac apoptosis and dysfunction, associated with inhibition of NF-kappaB activity, suggesting that Hsp20 may be a new therapeutic agent for the treatment of sepsis.
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Affiliation(s)
- Xiaohong Wang
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575, USA
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