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Gao Q, Zhang C, Xu X, Huang X, Jia D, Shan Y, Fang W, Li X, Xu J. The death domain-associated protein suppresses porcine epidemic diarrhea virus replication by interacting with signal transducer and activator of transcription 1 and inducing downstream ISG15 expression. Vet Microbiol 2024; 292:110065. [PMID: 38564904 DOI: 10.1016/j.vetmic.2024.110065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 03/21/2024] [Accepted: 03/23/2024] [Indexed: 04/04/2024]
Abstract
Porcine epidemic diarrhea virus (PEDV) is an enteric coronavirus that causes acute enteric disease in piglets and severely threatens the pig industry all over the world. Death domain-associated protein (DAXX) is a classical chaperone protein involved in multiple biological processes, such as cell apoptosis, transcriptional regulation, DNA damage repair, and host innate immunity. However, whether DAXX functions in the anti-PEDV innate immune responses remains unclear. In this study, we found that PEDV infection upregulated DAXX expression and induced its nucleocytoplasmic translocation in IPEC-J2 cells. Furthermore, we found that DAXX overexpression was inhibitory to PEDV replication, while downregulation of DAXX by RNA interference facilitated PEDV replication. The antiviral activity of DAXX was due to its positive effect on IFN-λ3-STAT1 signaling, as DAXX positively regulated STAT1 activation through their interaction in cytoplasm and enhancing the downstream ISG15 expression. Mutation of tryptophan at 621 to alanine in DAXX increased its abundance in the cytoplasm, leading to the upregulation of STAT1 phosphorylation and ISG15 expression. It indicated that cytoplasmic fraction of DAXX was advantageous for the STAT1-ISG15 signaling axis and PEDV inhibition. In summary, these results show that DAXX inhibits PEDV infection by increasing IFN-λ3-induced STAT1 phosphorylation and the downstream ISG15 expression.
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Affiliation(s)
- Qin Gao
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Chuni Zhang
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaohan Xu
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaoqi Huang
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Dekai Jia
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Ying Shan
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China; Zhejiang Province Key Laboratory of Veterinary Medicine, MOA Key Laboratory of Animal Virology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Weihuan Fang
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China; Zhejiang Province Key Laboratory of Veterinary Medicine, MOA Key Laboratory of Animal Virology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaoliang Li
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China; Zhejiang Province Key Laboratory of Veterinary Medicine, MOA Key Laboratory of Animal Virology, Zhejiang University, Hangzhou, Zhejiang 310058, China; The Rural Development Academy, Zhejiang University, Hangzhou, Zhejiang 310058, China.
| | - Jidong Xu
- Department of Veterinary Medicine, College of Animal Sciences, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China; Zhejiang Province Key Laboratory of Veterinary Medicine, MOA Key Laboratory of Animal Virology, Zhejiang University, Hangzhou, Zhejiang 310058, China.
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Singh MK, Shin Y, Ju S, Han S, Choe W, Yoon KS, Kim SS, Kang I. Heat Shock Response and Heat Shock Proteins: Current Understanding and Future Opportunities in Human Diseases. Int J Mol Sci 2024; 25:4209. [PMID: 38673794 PMCID: PMC11050489 DOI: 10.3390/ijms25084209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 04/03/2024] [Accepted: 04/05/2024] [Indexed: 04/28/2024] Open
Abstract
The heat shock response is an evolutionarily conserved mechanism that protects cells or organisms from the harmful effects of various stressors such as heat, chemicals toxins, UV radiation, and oxidizing agents. The heat shock response triggers the expression of a specific set of genes and proteins known as heat shock genes/proteins or molecular chaperones, including HSP100, HSP90, HSP70, HSP60, and small HSPs. Heat shock proteins (HSPs) play a crucial role in thermotolerance and aiding in protecting cells from harmful insults of stressors. HSPs are involved in essential cellular functions such as protein folding, eliminating misfolded proteins, apoptosis, and modulating cell signaling. The stress response to various environmental insults has been extensively studied in organisms from prokaryotes to higher organisms. The responses of organisms to various environmental stressors rely on the intensity and threshold of the stress stimuli, which vary among organisms and cellular contexts. Studies on heat shock proteins have primarily focused on HSP70, HSP90, HSP60, small HSPs, and ubiquitin, along with their applications in human biology. The current review highlighted a comprehensive mechanism of heat shock response and explores the function of heat shock proteins in stress management, as well as their potential as therapeutic agents and diagnostic markers for various diseases.
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Affiliation(s)
- Manish Kumar Singh
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; (M.K.S.); (Y.S.); (S.J.); (S.H.); (W.C.); (K.-S.Y.)
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Yoonhwa Shin
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; (M.K.S.); (Y.S.); (S.J.); (S.H.); (W.C.); (K.-S.Y.)
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Songhyun Ju
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; (M.K.S.); (Y.S.); (S.J.); (S.H.); (W.C.); (K.-S.Y.)
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Sunhee Han
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; (M.K.S.); (Y.S.); (S.J.); (S.H.); (W.C.); (K.-S.Y.)
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Wonchae Choe
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; (M.K.S.); (Y.S.); (S.J.); (S.H.); (W.C.); (K.-S.Y.)
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Kyung-Sik Yoon
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; (M.K.S.); (Y.S.); (S.J.); (S.H.); (W.C.); (K.-S.Y.)
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Sung Soo Kim
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; (M.K.S.); (Y.S.); (S.J.); (S.H.); (W.C.); (K.-S.Y.)
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Insug Kang
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; (M.K.S.); (Y.S.); (S.J.); (S.H.); (W.C.); (K.-S.Y.)
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
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Sanjeev D, George M, John L, Gopalakrishnan AP, Priyanka P, Mendon S, Yandigeri T, Nisar M, Nisar M, Kanekar S, Balaya RDA, Raju R. Tyr352 as a Predominant Phosphosite in the Understudied Kinase and Molecular Target, HIPK1: Implications for Cancer Therapy. OMICS : A JOURNAL OF INTEGRATIVE BIOLOGY 2024; 28:111-124. [PMID: 38498023 DOI: 10.1089/omi.2023.0244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Homeodomain-interacting protein kinase 1 (HIPK1) is majorly found in the nucleoplasm. HIPK1 is associated with cell proliferation, tumor necrosis factor-mediated cellular apoptosis, transcription regulation, and DNA damage response, and thought to play significant roles in health and common diseases such as cancer. Despite this, HIPK1 remains an understudied molecular target. In the present study, based on a systematic screening and mapping approach, we assembled 424 qualitative and 44 quantitative phosphoproteome datasets with 15 phosphosites in HIPK1 reported across multiple studies. These HIPK1 phosphosites were not currently attributed to any functions. Among them, Tyr352 within the kinase domain was identified as the predominant phosphosite modulated in 22 differential datasets. To analyze the functional association of HIPK1 Tyr352, we first employed a stringent criterion to derive its positively and negatively correlated protein phosphosites. Subsequently, we categorized the correlated phosphosites in known interactors, known/predicted kinases, and substrates of HIPK1, for their prioritized validation. Bioinformatics analysis identified their significant association with biological processes such as the regulation of RNA splicing, DNA-templated transcription, and cellular metabolic processes. HIPK1 Tyr352 was also identified to be upregulated in Her2+ cell lines and a subset of pancreatic and cholangiocarcinoma tissues. These data and the systems biology approach undertaken in the present study serve as a platform to explore the functional role of other phosphosites in HIPK1, and by extension, inform cancer drug discovery and oncotherapy innovation. In all, this study highlights the comprehensive phosphosite map of HIPK1 kinase and the first of its kind phosphosite-centric analysis of HIPK1 kinase based on global-level phosphoproteomics datasets derived from human cellular differential experiments across distinct experimental conditions.
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Affiliation(s)
- Diya Sanjeev
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | - Mejo George
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | - Levin John
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | | | - Pahal Priyanka
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | - Spoorthi Mendon
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | - Tanuja Yandigeri
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | - Mahammad Nisar
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | - Muhammad Nisar
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | - Saptami Kanekar
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
| | | | - Rajesh Raju
- Centre for Integrative Omics Data Science (CIODS), Yenepoya (Deemed-to-be University), Mangalore, Karnataka, India
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Anandakrishnan M, Ross KE, Chen C, Shanker V, Cowart J, Wu CH. KSFinder-a knowledge graph model for link prediction of novel phosphorylated substrates of kinases. PeerJ 2023; 11:e16164. [PMID: 37818330 PMCID: PMC10561642 DOI: 10.7717/peerj.16164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 09/01/2023] [Indexed: 10/12/2023] Open
Abstract
Background Aberrant protein kinase regulation leading to abnormal substrate phosphorylation is associated with several human diseases. Despite the promise of therapies targeting kinases, many human kinases remain understudied. Most existing computational tools predicting phosphorylation cover less than 50% of known human kinases. They utilize local feature selection based on protein sequences, motifs, domains, structures, and/or functions, and do not consider the heterogeneous relationships of the proteins. In this work, we present KSFinder, a tool that predicts kinase-substrate links by capturing the inherent association of proteins in a network comprising 85% of the known human kinases. We also postulate the potential role of two understudied kinases based on their substrate predictions from KSFinder. Methods KSFinder learns the semantic relationships in a phosphoproteome knowledge graph using a knowledge graph embedding algorithm and represents the nodes in low-dimensional vectors. A multilayer perceptron (MLP) classifier is trained to discern kinase-substrate links using the embedded vectors. KSFinder uses a strategic negative generation approach that eliminates biases in entity representation and combines data from experimentally validated non-interacting protein pairs, proteins from different subcellular locations, and random sampling. We assess KSFinder's generalization capability on four different datasets and compare its performance with other state-of-the-art prediction models. We employ KSFinder to predict substrates of 68 "dark" kinases considered understudied by the Illuminating the Druggable Genome program and use our text-mining tool, RLIMS-P along with manual curation, to search for literature evidence for the predictions. In a case study, we performed functional enrichment analysis for two dark kinases - HIPK3 and CAMKK1 using their predicted substrates. Results KSFinder shows improved performance over other kinase-substrate prediction models and generalized prediction ability on different datasets. We identified literature evidence for 17 novel predictions involving an understudied kinase. All of these 17 predictions had a probability score ≥0.7 (nine at >0.9, six at 0.8-0.9, and two at 0.7-0.8). The evaluation of 93,593 negative predictions (probability ≤0.3) identified four false negatives. The top enriched biological processes of HIPK3 substrates relate to the regulation of extracellular matrix and epigenetic gene expression, while CAMKK1 substrates include lipid storage regulation and glucose homeostasis. Conclusions KSFinder outperforms the current kinase-substrate prediction tools with higher kinase coverage. The strategically developed negatives provide a superior generalization ability for KSFinder. We predicted substrates of 432 kinases, 68 of which are understudied, and hypothesized the potential functions of two dark kinases using their predicted substrates.
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Affiliation(s)
- Manju Anandakrishnan
- Center for Bioinformatics and Computational Biology, University of Delware, Newark, DE, United States of America
| | - Karen E. Ross
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Chuming Chen
- Center for Bioinformatics and Computational Biology, University of Delware, Newark, DE, United States of America
| | - Vijay Shanker
- Center for Bioinformatics and Computational Biology, University of Delware, Newark, DE, United States of America
| | - Julie Cowart
- Center for Bioinformatics and Computational Biology, University of Delware, Newark, DE, United States of America
| | - Cathy H. Wu
- Center for Bioinformatics and Computational Biology, University of Delware, Newark, DE, United States of America
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC, United States of America
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5
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Bei Y, Zhu Y, Wei M, Yin M, Li L, Chen C, Huang Z, Liang X, Gao J, Yao J, van der Kraak PH, Vink A, Lei Z, Dai Y, Chen H, Liang Y, Sluijter JPG, Xiao J. HIPK1 Inhibition Protects against Pathological Cardiac Hypertrophy by Inhibiting the CREB-C/EBPβ Axis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2300585. [PMID: 37098980 PMCID: PMC10288234 DOI: 10.1002/advs.202300585] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 04/04/2023] [Indexed: 06/19/2023]
Abstract
Inhibition of pathological cardiac hypertrophy is recognized as an important therapeutic strategy for heart failure, although effective targets are still lacking in clinical practice. Homeodomain interacting protein kinase 1 (HIPK1) is a conserved serine/threonine kinase that can respond to different stress signals, however, whether and how HIPK1 regulates myocardial function is not reported. Here, it is observed that HIPK1 is increased during pathological cardiac hypertrophy. Both genetic ablation and gene therapy targeting HIPK1 are protective against pathological hypertrophy and heart failure in vivo. Hypertrophic stress-induced HIPK1 is present in the nucleus of cardiomyocytes, while HIPK1 inhibition prevents phenylephrine-induced cardiomyocyte hypertrophy through inhibiting cAMP-response element binding protein (CREB) phosphorylation at Ser271 and inactivating CCAAT/enhancer-binding protein β (C/EBPβ)-mediated transcription of pathological response genes. Inhibition of HIPK1 and CREB forms a synergistic pathway in preventing pathological cardiac hypertrophy. In conclusion, HIPK1 inhibition may serve as a promising novel therapeutic strategy to attenuate pathological cardiac hypertrophy and heart failure.
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Affiliation(s)
- Yihua Bei
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Yujiao Zhu
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Meng Wei
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Mingming Yin
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Lin Li
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Chen Chen
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Zhenzhen Huang
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Xuchun Liang
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Juan Gao
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
| | - Jianhua Yao
- Department of CardiologyShanghai Tenth People's HospitalTongji University School of MedicineShanghai200072China
- Department of CardiologyShigatse People's HospitalTibet857000China
| | - Petra H. van der Kraak
- Department of PathologyUniversity Medical Center UtrechtUniversity UtrechtUtrecht3584 CXThe Netherlands
| | - Aryan Vink
- Department of PathologyUniversity Medical Center UtrechtUniversity UtrechtUtrecht3584 CXThe Netherlands
| | - Zhiyong Lei
- Department of CardiologyLaboratory of Experimental CardiologyUniversity Medical Center UtrechtUniversity UtrechtUtrecht3584 CXThe Netherlands
- Division LabCentral Diagnosis Laboratory ResearchUniversity Medical Center UtrechtUniversity UtrechtUtrecht3584 CXThe Netherlands
| | - Yuxiang Dai
- Shanghai Institute of Cardiovascular DiseasesZhongshan HospitalFudan UniversityShanghai200032China
| | - Huihua Chen
- School of Basic Medical ScienceShanghai University of Traditional Chinese MedicineShanghai201203China
| | - Yueyang Liang
- School of Basic Medical ScienceShanghai University of Traditional Chinese MedicineShanghai201203China
| | - Joost PG Sluijter
- Department of CardiologyLaboratory of Experimental CardiologyUniversity Medical Center UtrechtUniversity UtrechtUtrecht3584 CXThe Netherlands
- UMC Utrecht Regenerative Medicine CenterUniversity Medical Center UtrechtUtrecht3508 GAThe Netherlands
| | - Junjie Xiao
- Institute of Geriatrics (Shanghai University)Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)School of MedicineShanghai UniversityNantong226011China
- Cardiac Regeneration and Ageing LabInstitute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai200444China
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Lazaro-Pena MI, Cornwell AB, Diaz-Balzac CA, Das R, Macoretta N, Thakar J, Samuelson AV. Homeodomain-interacting protein kinase maintains neuronal homeostasis during normal Caenorhabditis elegans aging and systemically regulates longevity from serotonergic and GABAergic neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.11.523661. [PMID: 36711523 PMCID: PMC9882034 DOI: 10.1101/2023.01.11.523661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Aging and the age-associated decline of the proteome is determined in part through neuronal control of evolutionarily conserved transcriptional effectors, which safeguard homeostasis under fluctuating metabolic and stress conditions by regulating an expansive proteostatic network. We have discovered the Caenorhabditis elegans h omeodomain-interacting p rotein k inase (HPK-1) acts as a key transcriptional effector to preserve neuronal integrity, function, and proteostasis during aging. Loss of hpk-1 results in drastic dysregulation in expression of neuronal genes, including genes associated with neuronal aging. During normal aging hpk-1 expression increases throughout the nervous system more broadly than any other kinase. Within the aging nervous system, hpk-1 is co-expressed with key longevity transcription factors, including daf-16 (FOXO), hlh-30 (TFEB), skn-1 (Nrf2), and hif-1 , which suggests hpk-1 expression mitigates natural age-associated physiological decline. Consistently, pan-neuronal overexpression of hpk-1 extends longevity, preserves proteostasis both within and outside of the nervous system, and improves stress resistance. Neuronal HPK-1 improves proteostasis through kinase activity. HPK-1 functions cell non-autonomously within serotonergic and GABAergic neurons to improve proteostasis in distal tissues by specifically regulating distinct components of the proteostatic network. Increased serotonergic HPK-1 enhances the heat shock response and survival to acute stress. In contrast, GABAergic HPK-1 induces basal autophagy and extends longevity. Our work establishes hpk-1 as a key neuronal transcriptional regulator critical for preservation of neuronal function during aging. Further, these data provide novel insight as to how the nervous system partitions acute and chronic adaptive response pathways to delay aging by maintaining organismal homeostasis.
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7
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Liu Z, Tardat M, Gill ME, Royo H, Thierry R, Ozonov EA, Peters AH. SUMOylated PRC1 controls histone H3.3 deposition and genome integrity of embryonic heterochromatin. EMBO J 2020; 39:e103697. [PMID: 32395866 PMCID: PMC7327501 DOI: 10.15252/embj.2019103697] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 04/09/2020] [Accepted: 04/14/2020] [Indexed: 12/14/2022] Open
Abstract
Chromatin integrity is essential for cellular homeostasis. Polycomb group proteins modulate chromatin states and transcriptionally repress developmental genes to maintain cell identity. They also repress repetitive sequences such as major satellites and constitute an alternative state of pericentromeric constitutive heterochromatin at paternal chromosomes (pat‐PCH) in mouse pre‐implantation embryos. Remarkably, pat‐PCH contains the histone H3.3 variant, which is absent from canonical PCH at maternal chromosomes, which is marked by histone H3 lysine 9 trimethylation (H3K9me3), HP1, and ATRX proteins. Here, we show that SUMO2‐modified CBX2‐containing Polycomb Repressive Complex 1 (PRC1) recruits the H3.3‐specific chaperone DAXX to pat‐PCH, enabling H3.3 incorporation at these loci. Deficiency of Daxx or PRC1 components Ring1 and Rnf2 abrogates H3.3 incorporation, induces chromatin decompaction and breakage at PCH of exclusively paternal chromosomes, and causes their mis‐segregation. Complementation assays show that DAXX‐mediated H3.3 deposition is required for chromosome stability in early embryos. DAXX also regulates repression of PRC1 target genes during oogenesis and early embryogenesis. The study identifies a novel critical role for Polycomb in ensuring heterochromatin integrity and chromosome stability in mouse early development.
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Affiliation(s)
- Zichuan Liu
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Mathieu Tardat
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Mark E Gill
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Helene Royo
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Raphael Thierry
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Evgeniy A Ozonov
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Antoine Hfm Peters
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,Faculty of Sciences, University of Basel, Basel, Switzerland
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8
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Xiao Q, Hu Y, Yang X, Tang J, Wang X, Xue X, Li M, Wang M, Zhao Y, Liu J, Wang H. Changes in Protein Phosphorylation during Salivary Gland Degeneration in Haemaphysalis longicornis. THE KOREAN JOURNAL OF PARASITOLOGY 2020; 58:161-171. [PMID: 32418385 PMCID: PMC7231830 DOI: 10.3347/kjp.2020.58.2.161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/10/2020] [Indexed: 01/19/2023]
Abstract
The ticks feed large amount of blood from their hosts and transmit pathogens to the victims. The salivary gland plays an important role in the blood feeding. When the female ticks are near engorgement, the salivary gland gradually loses its functions and begins to rapidly degenerate. In this study, data-independent acquisition quantitative proteomics was used to study changes in the phosphorylation modification of proteins during salivary gland degeneration in Haemaphysalis longicornis. In this quantitative study, 400 phosphorylated proteins and 850 phosphorylation modification sites were identified. Trough RNA interference experiments, we found that among the proteins with changes in phosphorylation, apoptosis-promoting Hippo protein played a role in salivary gland degeneration.
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Affiliation(s)
- Qi Xiao
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Yuhong Hu
- Instrumental Analysis Center, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Xiaohong Yang
- Department of Pathogenic Biology, College of Basic Medicine, Hebei Medical University, Shijiazhuang, Hebei 050017, PR China.,State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, PR China
| | - Jianna Tang
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Xiaoshuang Wang
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Xiaomin Xue
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Mengxue Li
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Minjing Wang
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Yinan Zhao
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Jingze Liu
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Hui Wang
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
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9
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Mahmud I, Liao D. DAXX in cancer: phenomena, processes, mechanisms and regulation. Nucleic Acids Res 2019; 47:7734-7752. [PMID: 31350900 PMCID: PMC6735914 DOI: 10.1093/nar/gkz634] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 07/05/2019] [Accepted: 07/12/2019] [Indexed: 12/13/2022] Open
Abstract
DAXX displays complex biological functions. Remarkably, DAXX overexpression is a common feature in diverse cancers, which correlates with tumorigenesis, disease progression and treatment resistance. Structurally, DAXX is modular with an N-terminal helical bundle, a docking site for many DAXX interactors (e.g. p53 and ATRX). DAXX's central region folds with the H3.3/H4 dimer, providing a H3.3-specific chaperoning function. DAXX has two functionally critical SUMO-interacting motifs. These modules are connected by disordered regions. DAXX's structural features provide a framework for deciphering how DAXX mechanistically imparts its functions and how its activity is regulated. DAXX modulates transcription through binding to transcription factors, epigenetic modifiers, and chromatin remodelers. DAXX's localization in the PML nuclear bodies also plays roles in transcriptional regulation. DAXX-regulated genes are likely important effectors of its biological functions. Deposition of H3.3 and its interactions with epigenetic modifiers are likely key events for DAXX to regulate transcription, DNA repair, and viral infection. Interactions between DAXX and its partners directly impact apoptosis and cell signaling. DAXX's activity is regulated by posttranslational modifications and ubiquitin-dependent degradation. Notably, the tumor suppressor SPOP promotes DAXX degradation in phase-separated droplets. We summarize here our current understanding of DAXX's complex functions with a focus on how it promotes oncogenesis.
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Affiliation(s)
- Iqbal Mahmud
- Department of Anatomy and Cell Biology, UF Health Cancer Center, University of Florida College of Medicine, 1333 Center Drive, Gainesville, FL 32610-0235, USA
| | - Daiqing Liao
- Department of Anatomy and Cell Biology, UF Health Cancer Center, University of Florida College of Medicine, 1333 Center Drive, Gainesville, FL 32610-0235, USA
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10
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Berchtold D, Battich N, Pelkmans L. A Systems-Level Study Reveals Regulators of Membrane-less Organelles in Human Cells. Mol Cell 2018; 72:1035-1049.e5. [DOI: 10.1016/j.molcel.2018.10.036] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 06/11/2018] [Accepted: 10/19/2018] [Indexed: 01/06/2023]
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11
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Liu Y, Qian L, Yang J, Huang H, Feng J, Li X, Bian T, Ke H, Liu J, Zhang J. The expression level and prognostic value of HIPK3 among non-small-cell lung cancer patients in China. Onco Targets Ther 2018; 11:7459-7469. [PMID: 30498360 PMCID: PMC6207246 DOI: 10.2147/ott.s166878] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Background Lung cancer is one of the most common malignancies in the world and is at the forefront of causes of all cancer deaths. Identification of new prognostic predictors or therapeutic targets might improve a patient's survival rate. Purpose The Homeodomain interacting protein kinases (HIPKs) function as modulators of cellular stress responses and regulate cell differentiation, proliferation and apoptosis, but the function of HIPK3 is remain unknown. Patients and methods We used quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting methods to detective the expression of HIPK3. A total of 206 samples were obtained from patients and Immunochemical evaluation to determine HIPK3 protein expression. HIPK3 protein levels in in non-small cell lung cancer (NSCLC) were correlated with the clinical characteristics of patients and their 5-year survival rate. In addition, HIPK3 knockdown by specific RNAi promoted cell proliferation, migration, and invasion in A549 and HCC827 cancer cell lines. Results The quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting methods to demonstrate that HIPK3 expression was significantly down-regulated in non-small cell lung cancer (NSCLC) tissues compared with that in normal lung tissues. At the same time, the results of immunohistochemistry assays showed that low expression of HIPK3 was significantly associated with pathology grade; tumor, node, and metastases (TNM) stage; lymph node metastasis; Ki-67 expression; and the 5-year survival rate in NSCLC patients. Univariate analysis revealed that HIPK3 expression, Ki-67 expression, tumor diameter, TNM stage, and age were significantly associated with a poor prognosis. The multivariable analysis illustrated that HIPK3, tumor diameter, TNM, Ki-67 expression, and age had effects on the overall survival of NSCLC patients independently. Kaplan-Meier survival curves revealed that NSCLC patients with a lower HIPK3 expression had a poorer prognosis. In addition, in vivo results also confirmed that HIPK3 over-expression could inhibit tumor growth. Conclusion Our findings confirmed that low expression of HIPK3 in NSCLC tissues was significantly correlated with poor survival rates after curative resection. HIPK3 could potentially be used as a valuable biomarker in the prognosis of the survival of NSCLC patients.
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Affiliation(s)
- Yifei Liu
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
| | - Li Qian
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
| | - Juanjuan Yang
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
| | - Hua Huang
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
| | - Jia Feng
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
| | - Xiaoli Li
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
| | - Tingting Bian
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
| | - Honggang Ke
- Department of Thoracic Surgery, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China
| | - Jian Liu
- Department of Chemotherapy, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
| | - Jianguo Zhang
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China,
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12
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Lombardi LM, Zaghlula M, Sztainberg Y, Baker SA, Klisch TJ, Tang AA, Huang EJ, Zoghbi HY. An RNA interference screen identifies druggable regulators of MeCP2 stability. Sci Transl Med 2018; 9:9/404/eaaf7588. [PMID: 28835516 DOI: 10.1126/scitranslmed.aaf7588] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 04/14/2016] [Accepted: 06/13/2017] [Indexed: 12/14/2022]
Abstract
Alterations in gene dosage due to copy number variation are associated with autism spectrum disorder, intellectual disability (ID), and other psychiatric disorders. The nervous system is so acutely sensitive to the dose of methyl-CpG-binding protein 2 (MeCP2) that even a twofold change in MeCP2 protein-either increased or decreased-results in distinct disorders with overlapping features including ID, autistic behavior, and severe motor dysfunction. Rett syndrome is caused by loss-of-function mutations in MECP2, whereas duplications spanning the MECP2 locus result in MECP2 duplication syndrome (MDS), which accounts for ~1% of X-linked ID. Despite evidence from mouse models that restoring MeCP2 can reverse the course of disease, there are currently no U.S. Food and Drug Administration-approved therapies available to clinically modulate MeCP2 abundance. We used a forward genetic screen against all known human kinases and phosphatases to identify druggable regulators of MeCP2 stability. Two putative modulators of MeCP2, HIPK2 (homeodomain-interacting protein kinase 2) and PP2A (protein phosphatase 2A), were validated as stabilizers of MeCP2 in vivo. Further, pharmacological inhibition of PP2A in vivo reduced MeCP2 in the nervous system and rescued both overexpression and motor abnormalities in a mouse model of MDS. Our findings reveal potential therapeutic targets for treating disorders of altered MECP2 dosage.
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Affiliation(s)
- Laura M Lombardi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Manar Zaghlula
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.,Graduate Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yehezkel Sztainberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
| | - Steven A Baker
- Department of Pathology, Stanford University School of Medicine, Palo Alto, CA 94305, USA
| | - Tiemo J Klisch
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
| | - Amy A Tang
- Department of Pathology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Eric J Huang
- Department of Pathology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA. .,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.,Graduate Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX 77030, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
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13
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Inwood S, Buehler E, Betenbaugh M, Lal M, Shiloach J. Identifying HIPK1 as Target of miR-22-3p Enhancing Recombinant Protein Production From HEK 293 Cell by Using Microarray and HTP siRNA Screen. Biotechnol J 2017; 13. [PMID: 28987030 DOI: 10.1002/biot.201700342] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 09/11/2017] [Indexed: 01/20/2023]
Abstract
Protein expression from human embryonic kidney cells (HEK 293) is an important tool for structural and clinical studies. It is previously shown that microRNAs (small, noncoding RNAs) are effective means for improved protein expression from these cells, and by conducting a high-throughput screening of the human microRNA library, several microRNAs are identified as potential candidates for improving expression. From these, miR-22-3p is chosen for further study since it increased the expression of luciferase, two membrane proteins and a secreted fusion protein with minimal effect on the cells' growth and viability. Since each microRNA can interact with several gene targets, it is of interest to identify the repressed genes for understanding and exploring the improved expression mechanism for further implementation. Here, the authors describe a novel approach for identification of the target genes by integrating the differential gene expression analysis with information obtained from our previously conducted high-throughput siRNA screening. The identified genes were validated as being involved in improving luciferase expression by using siRNA and qRT-PCR. Repressing the target gene, HIPK1, is found to increase luciferase and GPC3 expression 3.3- and 2.2-fold, respectively.
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Affiliation(s)
- Sarah Inwood
- Biotechnology Core Laboratory NIDDK, NIH, Bethesda, Maryland 20892, USA.,Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Eugen Buehler
- Chemical Genomics Center, National Center for Advancing Translational Sciences, NIH, Rockville, MD 20850
| | - Michael Betenbaugh
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Madhu Lal
- Chemical Genomics Center, National Center for Advancing Translational Sciences, NIH, Rockville, MD 20850
| | - Joseph Shiloach
- Biotechnology Core Laboratory NIDDK, NIH, Bethesda, Maryland 20892, USA
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14
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Subburaju S, Coleman AJ, Cunningham MG, Ruzicka WB, Benes FM. Epigenetic Regulation of Glutamic Acid Decarboxylase 67 in a Hippocampal Circuit. Cereb Cortex 2017; 27:5284-5293. [PMID: 27733539 PMCID: PMC6411031 DOI: 10.1093/cercor/bhw307] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/25/2016] [Accepted: 09/11/2016] [Indexed: 01/05/2023] Open
Abstract
GABAergic dysfunction in hippocampus, a key feature of schizophrenia (SZ), may contribute to cognitive impairment in this disorder. In stratum oriens (SO) of sector CA3/2 of the human hippocampus, a network of genes involved in the regulation of glutamic acid decarboxylase GAD67 has been identified. Several of the genes in this network including epigenetic factors histone deacetylase 1 (HDAC1) and death-associated protein 6 (DAXX), the GABAergic enzyme GAD65 as well as the kainate receptor (KAR) subunits GluR6 and 7 show significant changes in expression in this area in SZ. We have tested whether HDAC1 and DAXX regulate GAD67, GAD65, or GluR in the intact rodent hippocampus. Stereotaxic injections of lentiviral vectors bearing shRNAi sequences for HDAC1 and DAXX were delivered into the SO of CA3/2, followed by laser microdissection of individual transduced GABA neurons. Quantitative PCR (QPCR) analyses demonstrated that inhibition of HDAC1 and DAXX increased expression of GAD67, GAD65, and GluR6 mRNA. Inhibition of DAXX, but not HDAC1 resulted in a significant increase in GluR7 mRNA. Our data support the hypothesis that HDAC1 and DAXX play a central role in coordinating the expression of genes in the GAD67 regulatory pathway in the SO of CA3/2.
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MESH Headings
- Adaptor Proteins, Signal Transducing/antagonists & inhibitors
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- CA2 Region, Hippocampal/cytology
- CA2 Region, Hippocampal/metabolism
- CA3 Region, Hippocampal/cytology
- CA3 Region, Hippocampal/metabolism
- Cell Line
- Epigenesis, Genetic
- GABAergic Neurons/cytology
- GABAergic Neurons/metabolism
- Glutamate Decarboxylase/metabolism
- Histone Deacetylase 1/antagonists & inhibitors
- Histone Deacetylase 1/metabolism
- Male
- Molecular Chaperones
- Neural Pathways/cytology
- Neural Pathways/metabolism
- Nuclear Proteins/antagonists & inhibitors
- Nuclear Proteins/metabolism
- RNA, Messenger/metabolism
- Rats, Sprague-Dawley
- Receptors, Glutamate/metabolism
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Affiliation(s)
- Sivan Subburaju
- Program in Structural and Molecular Neuroscience, McLean
Hospital, Belmont, MA 02478,
USA
- Department of Psychiatry, Harvard Medical School, Boston, MA 02115,
USA
| | - Andrew J Coleman
- Program in Structural and Molecular Neuroscience, McLean
Hospital, Belmont, MA 02478,
USA
| | - Miles G Cunningham
- Program in Structural and Molecular Neuroscience, McLean
Hospital, Belmont, MA 02478,
USA
- Department of Psychiatry, Harvard Medical School, Boston, MA 02115,
USA
| | - W Brad Ruzicka
- Program in Structural and Molecular Neuroscience, McLean
Hospital, Belmont, MA 02478,
USA
- Department of Psychiatry, Harvard Medical School, Boston, MA 02115,
USA
| | - Francine M Benes
- Program in Structural and Molecular Neuroscience, McLean
Hospital, Belmont, MA 02478,
USA
- Department of Psychiatry, Harvard Medical School, Boston, MA 02115,
USA
- Program in Neuroscience, Harvard Medical
School, Boston, MA 02115,
USA
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15
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Das R, Melo JA, Thondamal M, Morton EA, Cornwell AB, Crick B, Kim JH, Swartz EW, Lamitina T, Douglas PM, Samuelson AV. The homeodomain-interacting protein kinase HPK-1 preserves protein homeostasis and longevity through master regulatory control of the HSF-1 chaperone network and TORC1-restricted autophagy in Caenorhabditis elegans. PLoS Genet 2017; 13:e1007038. [PMID: 29036198 PMCID: PMC5658188 DOI: 10.1371/journal.pgen.1007038] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/26/2017] [Accepted: 09/20/2017] [Indexed: 12/11/2022] Open
Abstract
An extensive proteostatic network comprised of molecular chaperones and protein clearance mechanisms functions collectively to preserve the integrity and resiliency of the proteome. The efficacy of this network deteriorates during aging, coinciding with many clinical manifestations, including protein aggregation diseases of the nervous system. A decline in proteostasis can be delayed through the activation of cytoprotective transcriptional responses, which are sensitive to environmental stress and internal metabolic and physiological cues. The homeodomain-interacting protein kinase (hipk) family members are conserved transcriptional co-factors that have been implicated in both genotoxic and metabolic stress responses from yeast to mammals. We demonstrate that constitutive expression of the sole Caenorhabditis elegans Hipk homolog, hpk-1, is sufficient to delay aging, preserve proteostasis, and promote stress resistance, while loss of hpk-1 is deleterious to these phenotypes. We show that HPK-1 preserves proteostasis and extends longevity through distinct but complementary genetic pathways defined by the heat shock transcription factor (HSF-1), and the target of rapamycin complex 1 (TORC1). We demonstrate that HPK-1 antagonizes sumoylation of HSF-1, a post-translational modification associated with reduced transcriptional activity in mammals. We show that inhibition of sumoylation by RNAi enhances HSF-1-dependent transcriptional induction of chaperones in response to heat shock. We find that hpk-1 is required for HSF-1 to induce molecular chaperones after thermal stress and enhances hormetic extension of longevity. We also show that HPK-1 is required in conjunction with HSF-1 for maintenance of proteostasis in the absence of thermal stress, protecting against the formation of polyglutamine (Q35::YFP) protein aggregates and associated locomotory toxicity. These functions of HPK-1/HSF-1 undergo rapid down-regulation once animals reach reproductive maturity. We show that HPK-1 fortifies proteostasis and extends longevity by an additional independent mechanism: induction of autophagy. HPK-1 is necessary for induction of autophagosome formation and autophagy gene expression in response to dietary restriction (DR) or inactivation of TORC1. The autophagy-stimulating transcription factors pha-4/FoxA and mxl-2/Mlx, but not hlh-30/TFEB or the nuclear hormone receptor nhr-62, are necessary for extended longevity resulting from HPK-1 overexpression. HPK-1 expression is itself induced by transcriptional mechanisms after nutritional stress, and post-transcriptional mechanisms in response to thermal stress. Collectively our results position HPK-1 at a central regulatory node upstream of the greater proteostatic network, acting at the transcriptional level by promoting protein folding via chaperone expression, and protein turnover via expression of autophagy genes. HPK-1 therefore provides a promising intervention point for pharmacological agents targeting the protein homeostasis system as a means of preserving robust longevity. Aging is the gradual and progressive decline of vitality. A hallmark of aging is the decay of protective mechanisms that normally preserve the robustness and resiliency of cells and tissues. Proteostasis is the term that applies specifically to those mechanisms that promote stability of the proteome, the collection of polypeptides that cells produce, by a combination of chaperone-assisted folding and degradation of misfolded or extraneous proteins. We have identified hpk-1 (encoding a homeodomain-interacting protein kinase) in the nematode C. elegans as an important transcriptional regulatory component of the proteostasis machinery. HPK-1 promotes proteostasis by linking two distinct mechanisms: first by stimulating chaperone gene expression via the heat shock transcription factor (HSF-1), and second by stimulating autophagy gene expression in opposition to the target of rapamycin (TOR) kinase signaling pathway. HPK-1 therefore provides an attractive target for interventions to preserve physiological resiliency during aging by preserving the overall health of the proteome.
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Affiliation(s)
- Ritika Das
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
- Department of Biology, University of Rochester, Rochester, New York, United States of America
| | - Justine A. Melo
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Manjunatha Thondamal
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Elizabeth A. Morton
- Department of Genome Sciences, University of Washington, Seattle, Washington, United States of America
| | - Adam B. Cornwell
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Beresford Crick
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Joung Heon Kim
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Elliot W. Swartz
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Todd Lamitina
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Peter M. Douglas
- Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Andrew V. Samuelson
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
- * E-mail:
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16
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Transcriptomic Variation during Spermiogenesis in Mouse Germ Cells. PLoS One 2016; 11:e0164874. [PMID: 27835637 PMCID: PMC5105947 DOI: 10.1371/journal.pone.0164874] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 10/03/2016] [Indexed: 11/19/2022] Open
Abstract
To explore variations in the transcription activity during spermiogenesis, round and elongated spermatids were collected from ICR/CD1 model mice using laser capture microdissection (LCM) and cauda epididymal sperm samples. The transcripts were sequenced using RNA-seq, and the reads were mapped to mm9. The majority of the reads (70%) in the round and elongated spermatids were mappable to known and predicted exons, but that in sperm was only 9%. The results of the distribution of reads suggested that alternative splicing was more complicated in sperm than in round and elongated spermatids. In the 19,127 genes, we detected the expression of 5,104 de novo genes and 91,112 alternative splicing events, and 12,105 were differentially expressed. Gene ontology (GO), InterPro domains, and KEGG revealed changes in gene transcription, mitochondrial protein translation, cellular components, and energy metabolism during spermiogenesis. The results provided considerable information about alternative splicing events, differentiallly expressed genes (DEGs), and novel transcriptions during spermiogenesis in mice.
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17
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Age-dependent differential expression of death-associated protein 6 (Daxx) in various peripheral tissues and different brain regions of C57BL/6 male mice. Biogerontology 2016; 17:817-828. [PMID: 27465500 DOI: 10.1007/s10522-016-9651-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/17/2016] [Indexed: 12/17/2022]
Abstract
Death-associated protein 6 (DAXX) is a ubiquitous protein implicated in various cellular processes such as apoptosis, tumorigenesis, development and transcription. The role of DAXX is however ambiguous and many contradictory results regarding its function in apoptosis upon various cellular stresses are described in the literature. In order to have a better understanding of the role of DAXX throughout the entire organism under physiological stress conditions, we have characterized the mRNA levels, protein expression and the proteolytic processing of DAXX in the normal aging process in peripheral organs and brain regions in C57BL/6 male mice. Overall, Daxx mRNA expression decreases with aging in the liver, kidney, heart, cortex and cerebellum. In contrast, an increase is observed in the striatum. The protein expression of DAXX and of its proteolytic fragments increases with aging in the kidney, heart and cortex. In liver and spleen, no changes are observed while in the striatum and cerebellum, certain forms increase and others decrease with age, suggesting that the functions of DAXX may be cell type dependent. This study provides important details regarding the expression and post-translational modifications of DAXX in aging in the entire organism and provides reference data for the deregulation observed in age-associated diseases.
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18
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Brazina J, Svadlenka J, Macurek L, Andera L, Hodny Z, Bartek J, Hanzlikova H. DNA damage-induced regulatory interplay between DAXX, p53, ATM kinase and Wip1 phosphatase. Cell Cycle 2015; 14:375-87. [PMID: 25659035 PMCID: PMC4353233 DOI: 10.4161/15384101.2014.988019] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Death domain-associated protein 6 (DAXX) is a histone chaperone, putative regulator of apoptosis and transcription, and candidate modulator of p53-mediated gene expression following DNA damage. DAXX becomes phosphorylated upon DNA damage, however regulation of this modification, and its relationship to p53 remain unclear. Here we show that in human cells exposed to ionizing radiation or genotoxic drugs etoposide and neocarzinostatin, DAXX became rapidly phosphorylated in an ATM kinase-dependent manner. Our deletion and site-directed mutagenesis experiments identified Serine 564 (S564) as the dominant ATM-targeted site of DAXX, and immunofluorescence experiments revealed localization of S564-phosphorylated DAXX to PML nuclear bodies. Furthermore, using a panel of human cell types, we identified the p53-regulated Wip1 protein phosphatase as a key negative regulator of DAXX phosphorylation at S564, both in vitro and in cells. Consistent with the emerging oncogenic role of Wip1, its DAXX-dephosphorylating impact was most apparent in cancer cell lines harboring gain-of-function mutant and/or overexpressed Wip1. Unexpectedly, while Wip1 depletion increased DAXX phosphorylation both before and after DNA damage and increased p53 stability and transcriptional activity, knock-down of DAXX impacted neither p53 stabilization nor p53-mediated expression of Gadd45a, Noxa, Mdm2, p21, Puma, Sesn2, Tigar or Wip1. Consistently, analyses of cells with genetic, TALEN-mediated DAXX deletion corroborated the notion that neither phosphorylated nor non-phosphorylated DAXX is required for p53-mediated gene expression upon DNA damage. Overall, we identify ATM kinase and Wip1 phosphatase as opposing regulators of DAXX-S564 phosphorylation, and propose that the role of DAXX phosphorylation and DAXX itself are independent of p53-mediated gene expression.
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Affiliation(s)
- Jan Brazina
- a Department of Cell Signaling and Apoptosis
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Dolence JJ, Gwin KA, Shapiro MB, Hsu FC, Shapiro VS, Medina KL. Cell extrinsic alterations in splenic B cell maturation in Flt3-ligand knockout mice. IMMUNITY INFLAMMATION AND DISEASE 2015; 3:103-17. [PMID: 26029370 PMCID: PMC4444153 DOI: 10.1002/iid3.54] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 02/25/2015] [Accepted: 02/26/2015] [Indexed: 11/29/2022]
Abstract
B lymphopoiesis in bone marrow (BM) is critical for maintaining a diverse peripheral B cell pool to fight infection and establish lifelong immunity. The generation of immature B cells is reduced in Flt3-ligand (FL-/-) mice leading to deficiencies in splenic B cells. Here, we sought to understand the cellular basis of the spleen B cell deficiency in FL-/- mice. Significant reductions in transitional (TS) and follicular (FO) B cells were found in FL-/- mice, and increased frequencies, but not absolute numbers, of marginal zone (MZ) B cells. BAFF-R expression on splenic B cells and serum levels of B cell activating factor (BAFF) was comparable to wildtype (WT) mice. Mixed BM chimeras revealed that the reductions in TS and FO B cells were cell extrinsic. FL administration into FL-/- mice restored the deficiency in TS B cells and normalized the MZ compartment. Ki67 analysis revealed a significant decrease in the proliferative capacity of TS B cells in FL-/- mice. A Bcl2 transgene did not rescue TS cells in FL-/- mice, uncoupling FL-deficiency to Bcl2-dependent survival pathways. Upregulation of CD1d expression and adoptive transfer experiments suggested MZ skewing in FL-/- mice. These findings support an integral role for Flt3 signaling in peripheral B cell maturation.
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Affiliation(s)
- Joseph J Dolence
- Department of Immunology, Mayo Clinic College of Medicine Rochester, MN, 55905
| | - Kimberly A Gwin
- Department of Immunology, Mayo Clinic College of Medicine Rochester, MN, 55905
| | - Mariya B Shapiro
- Department of Immunology, Mayo Clinic College of Medicine Rochester, MN, 55905
| | - Fan-Chi Hsu
- Department of Immunology, Mayo Clinic College of Medicine Rochester, MN, 55905 ; Mayo Graduate School, Mayo Clinic College of Medicine Rochester, MN, 55905
| | - Virginia S Shapiro
- Department of Immunology, Mayo Clinic College of Medicine Rochester, MN, 55905
| | - Kay L Medina
- Department of Immunology, Mayo Clinic College of Medicine Rochester, MN, 55905
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van der Laden J, Soppa U, Becker W. Effect of tyrosine autophosphorylation on catalytic activity and subcellular localisation of homeodomain-interacting protein kinases (HIPK). Cell Commun Signal 2015; 13:3. [PMID: 25630557 PMCID: PMC4353451 DOI: 10.1186/s12964-014-0082-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 12/30/2014] [Indexed: 12/18/2022] Open
Abstract
Background Homeodomain interacting protein kinases (HIPKs) function as modulators of cellular stress responses and regulate cell differentiation, proliferation and apoptosis. The HIPK family includes HIPK1, HIPK2 and HIPK3, which share a similar domain structure, and the more distantly related HIPK4. Although HIPKs phosphorylate their substrates on serine or threonine residues, it was recently reported that HIPK2 depends on the autophosphorylation of a conserved tyrosine in the activation loop to acquire full catalytic activity and correct subcellular localization. In this study we addressed the question whether tyrosine autophosphorylation in the activation loop has a similar function in the other members of the HIPK family. Results All HIPKs contained phosphotyrosine when expressed in HeLa cells. Catalytically inactive point mutants were not tyrosine-phosphorylated, indicating that HIPKs are dual-specificity protein kinases that autophosphorylate on tyrosine residues. HIPK point mutants lacking the conserved tyrosine residue in the activation loop showed reduced catalytic activity towards peptide and protein substrates. Analysis of these mutants revealed that HIPK1, HIPK2 and HIPK3 but not HIPK4 are capable of autophosphorylating on other tyrosines. Inhibition of tyrosine phosphatase activity by treatment with vanadate enhanced global phosphotyrosine content of HIPK1, HIPK2 and HIPK3 but did not affect tyrosine phosphorylation in the activation loop. Mutation of the activation-loop tyrosines resulted in a redistribution of HIPK1 and HIPK2 from a speckle-like subnuclear compartment to the cytoplasm, whereas catalytically inactive point mutants showed the same pattern of cellular distribution as the wild type proteins. In contrast, mutation of the activating tyrosine did not increase the low percentage of cells with extranuclear HIPK3. HIPK4 was excluded from the nucleus with no difference between the wild type kinase and the point mutants. Conclusions These results show that HIPKs share the mechanism of activation by tyrosine autophosphorylation with the closely related DYRK family (dual-specificity tyrosine phosphorylation regulated kinase). However, members of the HIPK family differ regarding the subcellular localization and its dependence on tyrosine autophosphorylation. Electronic supplementary material The online version of this article (doi:10.1186/s12964-014-0082-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jan van der Laden
- Institute of Pharmacology and Toxicology, RWTH Aachen University, Wendlingweg 2, 52057, Aachen, Germany.
| | - Ulf Soppa
- Institute of Pharmacology and Toxicology, RWTH Aachen University, Wendlingweg 2, 52057, Aachen, Germany.
| | - Walter Becker
- Institute of Pharmacology and Toxicology, RWTH Aachen University, Wendlingweg 2, 52057, Aachen, Germany.
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Racimo F, Kuhlwilm M, Slatkin M. A test for ancient selective sweeps and an application to candidate sites in modern humans. Mol Biol Evol 2014; 31:3344-58. [PMID: 25172957 PMCID: PMC4245817 DOI: 10.1093/molbev/msu255] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
We introduce a new method to detect ancient selective sweeps centered on a candidate site. We explored different patterns produced by sweeps around a fixed beneficial mutation, and found that a particularly informative statistic measures the consistency between majority haplotypes near the mutation and genotypic data from a closely related population. We incorporated this statistic into an approximate Bayesian computation (ABC) method that tests for sweeps at a candidate site. We applied this method to simulated data and show that it has some power to detect sweeps that occurred more than 10,000 generations in the past. We also applied it to 1,000 Genomes and Complete Genomics data combined with high-coverage Denisovan and Neanderthal genomes to test for sweeps in modern humans since the separation from the Neanderthal–Denisovan ancestor. We tested sites at which humans are fixed for the derived (i.e., nonchimpanzee allele) whereas the Neanderthal and Denisovan genomes are homozygous for the ancestral allele. We observe only weak differences in statistics indicative of selection between functional categories. When we compare patterns of scaled diversity or use our ABC approach, we fail to find a significant difference in signals of classic selective sweeps between regions surrounding nonsynonymous and synonymous changes, but we detect a slight enrichment for reduced scaled diversity around splice site changes. We also present a list of candidate sites that show high probability of having undergone a classic sweep in the modern human lineage since the split from Neanderthals and Denisovans.
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Affiliation(s)
- Fernando Racimo
- Department of Integrative Biology, University of California, Berkeley Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Martin Kuhlwilm
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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22
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Rey C, Soubeyran I, Mahouche I, Pedeboscq S, Bessede A, Ichas F, De Giorgi F, Lartigue L. HIPK1 drives p53 activation to limit colorectal cancer cell growth. Cell Cycle 2013; 12:1879-91. [PMID: 23676219 DOI: 10.4161/cc.24927] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
HIPK1 (homeodomain interacting protein kinase 1) is a serine/threonine kinase that belongs to the CMGC superfamily. Emerging data point to the role of HIPK1 in cancer, but it is still not clear whether it acts as a tumor suppressor or promoter. Here we identified HIPK1 as a kinase that is significantly overexpressed in colorectal cancer (CRC) and whose expression is stage-dependent. Being abundantly expressed at the onset of the disease, the HIPK1 level gradually decreased as tumor stage progressed. To further uncover how this factor regulates tumorigenesis and establish whether it constitutes an early factor necessary for neoplastic transformation or for cellular defense, we studied the effect of its overexpression in vitro by investigating various cancer-related signaling cascades. We found that HIPK1 mostly regulates the p53 signaling pathway both in HCT116 and HeLa cells. By phosphorylating p53 on its serine-15, HIPK1 favored its transactivation potential, which led to a rise in p21 protein level and a decline in cell proliferation. Assuming that HIPK1 could impede CRC growth by turning on the p53/p21 pathway, we then checked p21 mRNA levels in patients. Interestingly, p21 transcripts were only increased in a subset of patients expressing high levels of HIPK1. Unlike the rest of the cohort, the majority of these patients hosted a native p53 protein, meaning that such a pro-survival pathway (HIPK1+ > p53 > p21) is active in patients, and that HIPK1 acts rather as a tumor suppressor.
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Affiliation(s)
- Christophe Rey
- INSERM U916, Institut Bergonié, Université de Bordeaux, Bordeaux, France
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23
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Halder UC, Bhowmick R, Roy Mukherjee T, Nayak MK, Chawla-Sarkar M. Phosphorylation drives an apoptotic protein to activate antiapoptotic genes: paradigm of influenza A matrix 1 protein function. J Biol Chem 2013; 288:14554-14568. [PMID: 23548901 DOI: 10.1074/jbc.m112.447086] [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
During infection, viral proteins target cellular pathways that regulate cellular innate immune responses and cell death. We demonstrate that influenza A virus matrix 1 protein (M1), an established proapoptotic protein, activates nuclear factor-κB member RelB-mediated survival genes (cIAP1, cIAP2, and cFLIP), a function that is linked with its nuclear translocation during early infection. Death domain-associated protein 6 (Daxx) is a transcription co-repressor of the RelB-responsive gene promoters. During influenza virus infection M1 binds to and stabilizes Daxx protein by preventing its ubiquitination and proteasomal degradation. Binding of M1 with Daxx through its Daxx binding motif prevents binding of RelB and Daxx, resulting in up-regulation of survival genes. This interaction also prevents promoter recruitment of DNA methyltransferases (Dnmt1 and Dnmt3a) and lowers CpG methylation of the survival gene promoters, leading to the activation of these genes. Thus, M1 prevents repressional function of Daxx during infection, thereby exerting a survival role. In addition to its nuclear localization signal, translocation of M1 to the nucleus depends on cellular kinase-mediated phosphorylation as the protein kinase C inhibitor calphostin C effectively down-regulates virus replication. The study reconciles the ambiguity of dual antagonistic function of viral protein and potentiates a possible target to limit virus infection.
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Affiliation(s)
- Umesh Chandra Halder
- Division of Virology, National Institute of Cholera and Enteric Diseases, P-33 C.I.T. Road, Scheme-XM, Beliaghata, Kolkata 700010, India
| | - Rahul Bhowmick
- Division of Virology, National Institute of Cholera and Enteric Diseases, P-33 C.I.T. Road, Scheme-XM, Beliaghata, Kolkata 700010, India
| | - Tapasi Roy Mukherjee
- Division of Virology, National Institute of Cholera and Enteric Diseases, P-33 C.I.T. Road, Scheme-XM, Beliaghata, Kolkata 700010, India
| | - Mukti Kant Nayak
- Department of Zoology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
| | - Mamta Chawla-Sarkar
- Division of Virology, National Institute of Cholera and Enteric Diseases, P-33 C.I.T. Road, Scheme-XM, Beliaghata, Kolkata 700010, India.
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24
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Lee YS, Dayma Y, Park MY, Kim KI, Yoo SE, Kim E. Daxx is a key downstream component of receptor interacting protein kinase 3 mediating retinal ischemic cell death. FEBS Lett 2012; 587:266-71. [PMID: 23260419 DOI: 10.1016/j.febslet.2012.12.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 11/15/2012] [Accepted: 12/03/2012] [Indexed: 10/27/2022]
Abstract
Receptor-interacting protein 3 (RIP3) has been implicated in ischemic necrosis of retinal cells. An in silico analysis followed by experimental validation identified death associated protein (Daxx) as a novel substrate of RIP3. In vitro binding studies revealed that RIP3 binds to the serine/proline/threonine-rich domain (amino acid 625-740) of Daxx. Upon ischemic insult, RIP3 phosphorylated Daxx at Ser-668 in the retinal ganglion cells, triggering nuclear export of Daxx. Depletion of RIP3 significantly inhibited nuclear export of Daxx and attenuated cell death to a great extent. Collectively, the findings of this study demonstrate that phosphorylation of Daxx by RIP3 comprises an important part of ischemic necrosis in rat retinal ganglion cells.
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Affiliation(s)
- Yun-Suk Lee
- College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon 305-764, Republic of Korea
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25
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Park BW, Park S, Koo JS, Kim SI, Park JM, Cho JH, Park HS. Homeodomain-interacting protein kinase 1 (HIPK1) expression in breast cancer tissues. Jpn J Clin Oncol 2012; 42:1138-45. [PMID: 23071292 DOI: 10.1093/jjco/hys163] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE This study investigated the incidence and clinical significance of homeodomain-interacting protein kinase 1 expression in breast cancer patients. METHODS We investigated immunohistochemical homeodomain-interacting protein kinase 1 expression from tissue microarrays of 1032 patients. The association of homeodomain-interacting protein kinase 1 expression pattern, clinicopathologic factors and survival outcome was evaluated. Tumors with ≥10% stained cells were considered positive for homeodomain-interacting protein kinase 1. RESULTS Non-cancerous breast tissue, pTis and pT1mic lesions did not show homeodomain-interacting protein kinase 1 expression at any sites. Of the 859 invasive tumors, 124 (14.4%) showed homeodomain-interacting protein kinase 1 expression with three different expression patterns: cytoplasmic (2.4%), nuclear (6.3%), and both cytoplasmic and nuclear (5.7%). Cytoplasmic homeodomain-interacting protein kinase 1-positive tumors showed distinctive features such as fewer nodal metastases, but were frequently Grade III, estrogen receptor-negative, progesterone receptor-negative, HER2-positive, highly proliferative and molecular apocrine tumors. No significant difference in clinicopathologic features was identified between negative and nuclear homeodomain-interacting protein kinase 1-positive tumors. Both cytoplasmic and nuclear HIPK1-positive tumors represent frequent small size, node negativity and moderately differentiated features. Survival was not significantly different by homeodomain-interacting protein kinase 1 expression patterns. CONCLUSIONS Homeodomain-interacting protein kinase 1 expression was identified only in invasive breast cancer cells with three different patterns: cytoplasmic, nuclear, and both cytoplasmic and nuclear. Although the mechanism is not certain, the subcellular localization of HIPK1 expression is associated with tumor histopathologic characteristics and different functions.
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Affiliation(s)
- Byeong-Woo Park
- Department of Surgery and Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea.
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26
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Michod D, Bartesaghi S, Khelifi A, Bellodi C, Berliocchi L, Nicotera P, Salomoni P. Calcium-dependent dephosphorylation of the histone chaperone DAXX regulates H3.3 loading and transcription upon neuronal activation. Neuron 2012; 74:122-35. [PMID: 22500635 PMCID: PMC3657165 DOI: 10.1016/j.neuron.2012.02.021] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2012] [Indexed: 01/19/2023]
Abstract
Activity-dependent modifications of chromatin are believed to contribute to dramatic changes in neuronal circuitry. The mechanisms underlying these modifications are not fully understood. The histone variant H3.3 is incorporated in a replication-independent manner into different regions of the genome, including gene regulatory elements. It is presently unknown whether H3.3 deposition is involved in neuronal activity-dependent events. Here, we analyze the role of the histone chaperone DAXX in the regulation of H3.3 incorporation at activity-dependent gene loci. DAXX is found to be associated with regulatory regions of selected activity-regulated genes, where it promotes H3.3 loading upon membrane depolarization. DAXX loss not only affects H3.3 deposition but also impairs transcriptional induction of these genes. Calcineurin-mediated dephosphorylation of DAXX is a key molecular switch controlling its function upon neuronal activation. Overall, these findings implicate the H3.3 chaperone DAXX in the regulation of activity-dependent events, thus revealing a new mechanism underlying epigenetic modifications in neurons.
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Affiliation(s)
- David Michod
- Samantha Dickson Brain Cancer Unit, University College London Cancer Institute, London WC1E 6DD, UK
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27
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Homeodomain-interacting protein kinase (HIPK)-1 is required for splenic B cell homeostasis and optimal T-independent type 2 humoral response. PLoS One 2012; 7:e35533. [PMID: 22545114 PMCID: PMC3335840 DOI: 10.1371/journal.pone.0035533] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Accepted: 03/17/2012] [Indexed: 01/25/2023] Open
Abstract
The homeodomain-interacting protein kinase (HIPK) family is comprised of four highly related serine/threonine kinases originally identified as co-repressors for various homeodomain-containing transcription factors. The HIPKs have been shown to be involved in growth regulation and apoptosis, with numerous studies highlighting HIPK regulation of the tumor suppressor p53. In this study, we have discovered a B cell homeostatic defect in HIPK1-deficient (HIPK1−/−) mice. Lymphopoietic populations within the thymus and bone marrow of HIPK1−/− mice appeared normal based upon FACS analysis; however, the spleen exhibited a reduced number of total B cells with a significant loss of transitional-1 and follicular B cell populations. Interestingly, the marginal zone B cell population was expanded in HIPK1−/− mice, yielding an increased frequency of these cells. HIPK1−/− B cells exhibited impaired cell division in response to B cell receptor cross-linking in vitro based upon thymidine incorporation or CFSE dilution; however, the addition of CD40L rescued HIPK1−/− proliferation to wild-type levels. Despite the expanded MZ B cell population in the HIPK1−/− mice, the T-independent type 2 humoral response was impaired. These data identify HIPK1 as a novel kinase required for optimal B cell function in mice.
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28
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Lan HC, Wu CF, Shih HM, Chung BC. Death-associated protein 6 (Daxx) mediates cAMP-dependent stimulation of Cyp11a1 (P450scc) transcription. J Biol Chem 2011; 287:5910-6. [PMID: 22199361 DOI: 10.1074/jbc.m111.307603] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
SF-1 is a key transcription factor for all steroidogenic genes. It up-regulates the expression of the steroidogenic Cyp11a1 gene in the adrenal in a pathway stimulated by cAMP through HIPK3-mediated JNK/c-Jun phosphorylation. In the present study, we have investigated the factors mediating cAMP-dependent HIPK3 action to potentiate the activity of SF-1 for Cyp11a1 transcription in mouse adrenocortical Y1 cells. We found Daxx, a HIPK kinase substrate in the apoptosis pathway, was phosphorylated by HIPK3 at Ser-669 in response to cAMP stimulation. Daxx participated in SF-1-dependent Cyp11a1 expression as shown by experiments involving both overexpression and down-regulation via a dominant negative Daxx mutant. The S669A mutant of Daxx, which could not be phosphorylated by HIPK3, lost the ability to potentiate SF-1 activity for Cyp11a1 expression. The enhancement of SF-1 activity by Daxx required JNK and c-Jun phosphorylation. Thus, Daxx functioned as a signal transducer linking cAMP-stimulated HIPK3 activity with JNK/c-Jun phosphorylation and SF-1-dependent Cyp11a1 transcription for steroid synthesis.
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Affiliation(s)
- Hsin-Chieh Lan
- Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan
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29
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Huang H, Du G, Chen H, Liang X, Li C, Zhu N, Xue L, Ma J, Jiao R. Drosophila Smt3 negatively regulates JNK signaling through sequestering Hipk in the nucleus. Development 2011; 138:2477-85. [PMID: 21561986 DOI: 10.1242/dev.061770] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Post-translational modification by the small ubiquitin-related modifier (SUMO) is important for a variety of cellular and developmental processes. However, the precise mechanism(s) that connects sumoylation to specific developmental signaling pathways remains relatively less clear. Here, we show that Smt3 knockdown in Drosophila wing discs causes phenotypes resembling JNK gain of function, including ectopic apoptosis and apoptosis-induced compensatory growth. Smt3 depletion leads to an increased expression of JNK target genes Mmp1 and puckered. We show that, although knockdown of the homeodomain-interacting protein kinase (Hipk) suppresses Smt3 depletion-induced activation of JNK, Hipk overexpression synergistically enhances this type of JNK activation. We further demonstrate that Hipk is sumolylated in vivo, and its nuclear localization is dependent on the sumoylation pathway. Our results thus establish a mechanistic connection between the sumoylation pathway and the JNK pathway through the action of Hipk. We propose that the sumoylation-controlled balance between cytoplasmic and nuclear Hipk plays a crucial role in regulating JNK signaling.
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Affiliation(s)
- Hai Huang
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Datun Road 15, Beijing 100101, China
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30
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Wethkamp N, Hanenberg H, Funke S, Suschek CV, Wetzel W, Heikaus S, Grinstein E, Ramp U, Engers R, Gabbert HE, Mahotka C. Daxx-beta and Daxx-gamma, two novel splice variants of the transcriptional co-repressor Daxx. J Biol Chem 2011; 286:19576-88. [PMID: 21482821 DOI: 10.1074/jbc.m110.196311] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Daxx is involved in transcriptional control and apoptosis. It comprises several domains, including a regulatory C terminus that is responsible for the interaction with numerous proteins such as p53, promyelocytic leukemia protein (PML), and Hsp27. Here, we describe the identification and characterization of two novel variants of Daxx termed Daxx-β and Daxx-γ, which are generated by alternative splicing. Alternative splicing results in a truncated regulatory C terminus in both proteins. As a consequence, Daxx-β and Daxx-γ show a markedly decreased affinity to PML, which in turn is associated with a different subnuclear localization of these proteins compared with Daxx. Although Daxx is localized mainly in PML-oncogenic domains (PODs) Daxx-β and Daxx-γ display a distinct distribution pattern. Furthermore, Daxx-β and Daxx-γ show a decreased affinity to p53 also due to the truncated C terminus. We provide evidence that the p53 recruitment into PODs is Daxx isoform-dependent. The decreased affinity of Daxx-β/-γ to p53 and PML results in a diffuse localization of p53 throughout the nucleus. In contrast to Daxx, Daxx-β and Daxx-γ are unable to repress p53-mediated transcription. Therefore, alternative splicing of Daxx might indicate an additional level in the cellular apoptosis network.
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Affiliation(s)
- Nils Wethkamp
- Institute of Pathology, Heinrich Heine University, University Hospital, Medical Faculty, Düsseldorf, Germany
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31
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Escobar-Cabrera E, Lau DKW, Giovinazzi S, Ishov AM, McIntosh LP. Structural characterization of the DAXX N-terminal helical bundle domain and its complex with Rassf1C. Structure 2011; 18:1642-53. [PMID: 21134643 DOI: 10.1016/j.str.2010.09.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 09/06/2010] [Accepted: 09/08/2010] [Indexed: 12/27/2022]
Abstract
DAXX is a scaffold protein with diverse roles including transcription and cell cycle regulation. Using NMR spectroscopy, we demonstrate that the C-terminal half of DAXX is intrinsically disordered, whereas a folded domain is present near its N terminus. This domain forms a left-handed four-helix bundle (H1, H2, H4, H5). However, due to a crossover helix (H3), this topology differs from that of the Sin3 PAH domain, which to date has been used as a model for DAXX. The N-terminal residues of the tumor suppressor Rassf1C fold into an amphipathic α helix upon binding this DAXX domain via a shallow cleft along the flexible helices H2 and H5 (K(D) ∼60 μM). Based on a proposed DAXX recognition motif as hydrophobic residues preceded by negatively charged groups, we found that peptide models of p53 and Mdm2 also bound the helical bundle. These data provide a structural foundation for understanding the diverse functions of DAXX.
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Affiliation(s)
- Eric Escobar-Cabrera
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T1Z3, Canada
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32
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Regulation of cell cycle and DNA repair in post-mitotic GABA neurons in psychotic disorders. Neuropharmacology 2010; 60:1232-42. [PMID: 21184762 DOI: 10.1016/j.neuropharm.2010.12.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 11/24/2010] [Accepted: 12/15/2010] [Indexed: 11/24/2022]
Abstract
Disturbances of cell cycle regulation and DNA repair in post-mitotic neurons have been implicated in degenerative and malignant diseases of the human brain. Recent work is now suggesting that abnormal regulation of these functions in GABA cells of the adult hippocampus may also play a role in two neuropsychiatric disorders. In schizophrenia and bipolar disorder, a network of genes involved in the regulation of GAD₆₇, a marker for the functional differentiation of GABA cells, show pronounced changes in expression and include kainate receptor subunits, TGFβ and Wnt signaling pathways, epigenetic factors and transcription factors. One of these genes, cyclin D2, is involved in the regulation of cell cycle and DNA repair and appears to be a pivotal element in linking GAD₆₇ expression with these functional clusters of genes. Dysfunction of post-mitotic GABAergic neurons in the adult hippocampus of patients with psychotic disorders is associated with changes in the expression of genes that are involved in the maintenance of functional and genomic integrity of GABA cells. The nature of these changes is quite different in schizophrenia and bipolar disorder, suggesting that a common cell phenotype (in this case, decreased GAD₆₇ expression) may involve two fundamentally different molecular endophenotypes and reflect unique susceptibility genes involved in the respective disorders. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.
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33
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Chaudhary P, Sharma R, Sharma A, Vatsyayan R, Yadav S, Singhal SS, Rauniyar N, Prokai L, Awasthi S, Awasthi YC. Mechanisms of 4-hydroxy-2-nonenal induced pro- and anti-apoptotic signaling. Biochemistry 2010; 49:6263-75. [PMID: 20565132 DOI: 10.1021/bi100517x] [Citation(s) in RCA: 272] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In recent years, 4-hydroxy-2-nonenal (4-HNE) has emerged as an important second messenger in cell cycle signaling. Here, we demonstrate that 4-HNE induces signaling for apoptosis via both the Fas-mediated extrinsic and the p53-mediated intrinsic pathways in HepG2 cells. 4-HNE induces a Fas-mediated DISC independent apoptosis pathway by activating ASK1, JNK, and caspase-3. Parallel treatment of 4-HNE to HepG2 cells also induces apoptosis by the p53 pathway through activation of Bax, p21, JNK, and caspase-3. Exposure of HepG2 cells to 4-HNE leads to the activation of both Fas and Daxx, promotes the export of Daxx from the nucleus to cytoplasm, and facilitates Fas-Daxx binding. Depletion of Daxx by siRNA results in the potentiation of apoptosis, indicating that Fas-Daxx binding in fact is inhibitory to Fas-mediated apoptosis in cells. 4-HNE-induced translocation of Daxx is also accompanied by the activation and nuclear accumulation of HSF1 and up-regulation of heat shock protein Hsp70. All these effects of 4-HNE in cells can be attenuated by ectopic expression of hGSTA4-4, the isozyme of glutathione S-transferase with high activity for 4-HNE. Through immunoprecipitation and liquid chromatography-tandem mass spectrometry, we have demonstrated the covalent binding of 4-HNE to Daxx. We also demonstrate that 4-HNE modification induces phosphorylation of Daxx at Ser668 and Ser671 to facilitate its cytoplasmic export. These results indicate that while 4-HNE exhibits toxicity through several mechanisms, in parallel it evokes signaling for defense mechanisms to self-regulate its toxicity and can simultaneously affect multiple signaling pathways through its interactions with membrane receptors and transcription factors/repressors.
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Affiliation(s)
- Pankaj Chaudhary
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, Texas 76107, USA
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Tang J, Qu L, Pang M, Yang X. Daxx is reciprocally regulated by Mdm2 and Hausp. Biochem Biophys Res Commun 2010; 393:542-5. [PMID: 20153724 DOI: 10.1016/j.bbrc.2010.02.051] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 02/09/2010] [Indexed: 01/05/2023]
Abstract
Daxx is a multifunctional protein, regulating a wide range of important functions including apoptosis and transcription. However, the way Daxx is regulated is poorly understood. In our previous studies, we have found that Daxx forms a complex with the E3 ubiquitin ligase Mdm2 and the de-ubiquitinase Hausp. In the present work, we show that Daxx is ubiquitinated by Mdm2 in both in vitro and in vivo systems and Mdm2 reduces Daxx expression upon over-expression. We further demonstrate that Hausp critically controls the cellular level of Daxx most likely by inducing Daxx de-ubiquitination. These results reveal Mdm2 and Hausp as important regulators for Daxx functions by controlling Daxx ubiquitination and stability.
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Affiliation(s)
- Jun Tang
- State Key Laboratory of Agrobiotechnology, College of Veterinary Medicine, China Agricultural University, 2 Yuanmingyuan W. Rd., Haidian District, Beijing 100193, China.
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Regulation of ICP0-null mutant herpes simplex virus type 1 infection by ND10 components ATRX and hDaxx. J Virol 2010; 84:4026-40. [PMID: 20147399 DOI: 10.1128/jvi.02597-09] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Herpes simplex virus type 1 (HSV-1) immediate-early gene product ICP0 activates lytic infection and relieves cell-mediated repression of viral gene expression. This repression is conferred by preexisting cellular proteins and is commonly referred to as intrinsic antiviral resistance or intrinsic defense. PML and Sp100, two core components of nuclear substructures known as ND10 or PML nuclear bodies, contribute to intrinsic resistance, but it is clear that other proteins must also be involved. We have tested the hypothesis that additional ND10 factors, particularly those that are involved in chromatin remodeling, may have roles in intrinsic resistance against HSV-1 infection. The two ND10 component proteins investigated in this report are ATRX and hDaxx, which are known to interact with each other and comprise components of a repressive chromatin-remodeling complex. We generated stable cell lines in which endogenous ATRX or hDaxx expression is severely suppressed by RNA interference. We found increases in both gene expression and plaque formation induced by ICP0-null mutant HSV-1 in both ATRX- and hDaxx-depleted cells. Reconstitution of wild-type hDaxx expression reversed the effects of hDaxx depletion, but reconstitution with a mutant form of hDaxx unable to interact with ATRX did not. Our results suggest that ATRX and hDaxx act as a complex that contributes to intrinsic antiviral resistance to HSV-1 infection, which is counteracted by ICP0.
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He Q, Shi J, Sun H, An J, Huang Y, Sheikh MS. Characterization of Human Homeodomain-interacting Protein Kinase 4 (HIPK4) as a Unique Member of the HIPK Family. MOLECULAR AND CELLULAR PHARMACOLOGY 2010; 2:61-68. [PMID: 20508833 PMCID: PMC2876313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Homeodomain-interacting protein kinases including HIPK1, HIPK2 and HIPK3 are serine/threonine kinases that form a family of highly conserved kinases. HIPKs are involved in diverse cellular functions including regulation cell death, survival, proliferation and differentiation. Here we report the characterization of a human HIPK4 that we identified in a proteomic screen during our efforts to unravel novel markers linked to cell death and survival. Human HIPK4 protein is composed of 616 residues with predicted molecular mass of 69.425 kDa and harbors a serine/threonine protein kinase catalytic domain at its N-terminal end. In the in vitro kinase assay, HIPK4 exhibits kinase activity and mutation of the conserved lysine 40 or aspartic acid 136 residue in its catalytic domain inactivates its kinase function. Human HIPK4 harbors multiple putative serine/threonine- and tyrosine-specific phsophorylation sites and also contains four high probability sumoylation sites, findings that suggest its function to be modulated by post-translational modifications. HIPK4 has been so named in the database because of its sequence homology to HIPK1, 2 and 3 predominantly within its catalytic domain. However, HIPK4 is smaller in size than the known HIPKs and has additional distinct features suggesting it to be a unique member of the HIPK family. Further functional characterization of HIPK4 is needed and will prove valuable to ascertain whether it performs distinct functions or share overlapping functions with other HIPKs.
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Affiliation(s)
- Qin He
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, New York
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Kitamura T, Fukuyo Y, Inoue M, Horikoshi NT, Shindoh M, Rogers BE, Usheva A, Horikoshi N. Mutant p53 disrupts the stress MAPK activation circuit induced by ASK1-dependent stabilization of Daxx. Cancer Res 2009; 69:7681-8. [PMID: 19789335 DOI: 10.1158/0008-5472.can-09-2133] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Daxx is a regulatory protein for apoptosis signal-regulating kinase 1 (ASK1) which activates c-Jun NH2-terminal kinase (JNK) and p38 pathways in response to stressors such as tumor necrosis factor-alpha (TNFalpha). Here, we show that TNFalpha treatment induces the accumulation of Daxx protein through ASK1 activation by preventing its proteasome-dependent degradation. ASK1 directly phosphorylates Daxx at Ser(176) and Ser(184) and Daxx is required for the sustained activation of JNK. Tumorigenic mutant p53, which binds to Daxx and inhibits Daxx-dependent activation of ASK1, prevents Daxx phosphorylation and stabilization. When mutant p53 was depleted in cancer cells, Daxx was accumulated and the cell-killing effect of TNFalpha was restored. Our results indicate that Daxx not only activates ASK1 but also is a downstream target of ASK1 and that accumulated Daxx further activates ASK1. Thus, the Daxx-ASK1 positive feedback loop amplifying JNK/p38 signaling plays an important role in the cell-killing effects of stressors, such as TNFalpha. Tumorigenic mutant p53 disrupts this circuit and makes cells more tolerable to stresses, as its gain-of-function mechanism.
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Affiliation(s)
- Tetsuya Kitamura
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri, USA
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Gupta A, Hou R, Liu L, Hiroyasu S, Hadix JA, Huggins GS, Sibinga NES. Daxx inhibits muscle differentiation by repressing E2A-mediated transcription. J Cell Biochem 2009; 107:438-47. [PMID: 19308989 DOI: 10.1002/jcb.22140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The basic helix-loop-helix (HLH) E2A transcription factors bind to DNA as homodimers or as heterodimers formed with other basic HLH factors, activate gene expression, and promote differentiation of muscle, lymphoid, neuronal, and other cell types. These E2A functions can be inhibited by the Id proteins, HLH factors that sequester E2A in non-DNA binding dimers. Here we describe the direct interaction of E2A with Daxx, a broadly expressed non-HLH protein previously associated with apoptosis and transcriptional repression. Daxx inhibits E2A function, but not via an Id-like mechanism; rather, it recruits histone deacetylase activity to E2A-dependent promoters. Increased Daxx expression during muscle differentiation inhibits E2A-dependent expression of key myogenic genes and reduces myotube formation, while decreased Daxx expression promotes myotube formation. These results identify a new mechanism for limiting E2A activity and establish a link between Daxx-mediated gene regulation and control of cellular differentiation.
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Affiliation(s)
- Amitabh Gupta
- Department of Neurology, Johns Hopkins Hospital, Baltimore, Maryland 21287, USA
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Site-specific regulation of cell cycle and DNA repair in post-mitotic GABA cells in schizophrenic versus bipolars. Proc Natl Acad Sci U S A 2009; 106:11731-6. [PMID: 19564623 DOI: 10.1073/pnas.0903066106] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
GABA cell dysfunction in both schizophrenia (SZ) and bipolar disorder (BD) involves decreased GAD(67) expression, although this change involves fundamentally different networks of genes in the 2 disorders. One gene that is common to these 2 networks is cyclin D2, a key component of cell cycle regulation that shows increased expression in SZ, but decreased expression in BD. Because of the importance of cell cycle regulation in maintaining functional differentiation and DNA repair, the current study has examined the genes involved in the G(1) and G(2) checkpoints to generate new hypotheses regarding the regulation of the GABA cell phenotype in the hippocampus of SZ and BD. The results have demonstrated significant changes in cell cycle regulation in both SZ and BD and these changes include the transcriptional complex (TC) that controls the expression of E2F/DP-1 target genes critical for progression to G(2)/M. The methyl-CpG binding domain protein (MBD4) that is pivotal for DNA repair, is significantly up-regulated in the stratum oriens (SO) of CA3/2 and CA1 in SZs and BDs. However, other genes associated with the TC, and the G(1) and G(2) checkpoints, show complex changes in expression in the SO of CA3/2 and CA1 of both SZs and BDS. Overall, the patterns of expression observed have suggested that the regulation of functional differentiation and/or genomic integrity of hippocampal GABA cells varies according to diagnosis and their location within the trisynaptic pathway.
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McDonough H, Charles PC, Hilliard EG, Qian SB, Min JN, Portbury A, Cyr DM, Patterson C. Stress-dependent Daxx-CHIP interaction suppresses the p53 apoptotic program. J Biol Chem 2009; 284:20649-59. [PMID: 19465479 DOI: 10.1074/jbc.m109.011767] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Our previous studies have implicated CHIP (carboxyl terminus of Hsp70-interacting protein) as a co-chaperone/ubiquitin ligase whose activities yield protection against stress-induced apoptotic events. In this report, we demonstrate a stress-dependent interaction between CHIP and Daxx (death domain-associated protein). This interaction interferes with the stress-dependent association of HIPK2 with Daxx, blocking phosphorylation of serine 46 in p53 and inhibiting the p53-dependent apoptotic program. Microarray analysis confirmed suppression of the p53-dependent transcriptional portrait in CHIP(+/+) but not in CHIP(-/-) heat shocked mouse embryonic fibroblasts. The interaction between CHIP and Daxx results in ubiquitination of Daxx, which is then partitioned to an insoluble compartment of the cell. In vitro ubiquitination of Daxx by CHIP revealed that ubiquitin chain formation utilizes non-canonical lysine linkages associated with resistance to proteasomal degradation. The ubiquitination of Daxx by CHIP utilizes lysines 630 and 631 and competes with the sumoylation machinery of the cell at these residues. These studies implicate CHIP as a stress-dependent regulator of Daxx that counters the pro-apoptotic influence of Daxx in the cell. By abrogating p53-dependent apoptotic pathways and by ubiquitination competitive with Daxx sumoylation, CHIP integrates the proteotoxic stress response of the cell with cell cycle pathways that influence cell survival.
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Affiliation(s)
- Holly McDonough
- Carolina Cardiovascular Biology Center, University of North Carolina, Chapel Hill, North Carolina 27599-7126, USA
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Louie SH, Yang XY, Conrad WH, Muster J, Angers S, Moon RT, Cheyette BNR. Modulation of the beta-catenin signaling pathway by the dishevelled-associated protein Hipk1. PLoS One 2009; 4:e4310. [PMID: 19183803 PMCID: PMC2629544 DOI: 10.1371/journal.pone.0004310] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Accepted: 12/09/2008] [Indexed: 12/31/2022] Open
Abstract
Background Wnts are evolutionarily conserved ligands that signal through β-catenin-dependent and β-catenin–independent pathways to regulate cell fate, proliferation, polarity, and movements during vertebrate development. Dishevelled (Dsh/Dvl) is a multi-domain scaffold protein required for virtually all known Wnt signaling activities, raising interest in the identification and functions of Dsh-associated proteins. Methodology We conducted a yeast-2-hybrid screen using an N-terminal fragment of Dsh, resulting in isolation of the Xenopus laevis ortholog of Hipk1. Interaction between the Dsh and Hipk1 proteins was confirmed by co-immunoprecipitation assays and mass spectrometry, and further experiments suggest that Hipk1 also complexes with the transcription factor Tcf3. Supporting a nuclear function during X. laevis development, Myc-tagged Hipk1 localizes primarily to the nucleus in animal cap explants, and the endogenous transcript is strongly expressed during gastrula and neurula stages. Experimental manipulations of Hipk1 levels indicate that Hipk1 can repress Wnt/β-catenin target gene activation, as demonstrated by β-catenin reporter assays in human embryonic kidney cells and by indicators of dorsal specification in X. laevis embryos at the late blastula stage. In addition, a subset of Wnt-responsive genes subsequently requires Hipk1 for activation in the involuting mesoderm during gastrulation. Moreover, either over-expression or knock-down of Hipk1 leads to perturbed convergent extension cell movements involved in both gastrulation and neural tube closure. Conclusions These results suggest that Hipk1 contributes in a complex fashion to Dsh-dependent signaling activities during early vertebrate development. This includes regulating the transcription of Wnt/β-catenin target genes in the nucleus, possibly in both repressive and activating ways under changing developmental contexts. This regulation is required to modulate gene expression and cell movements that are essential for gastrulation.
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Affiliation(s)
- Sarah H. Louie
- Howard Hughes Medical Institute, Department of Pharmacology, and Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Xiao Yong Yang
- Department of Psychiatry, and Graduate Program in Developmental Biology, Program in Biological Sciences, University of California San Francisco, San Francisco, California, United States of America
| | - William H. Conrad
- Howard Hughes Medical Institute, Department of Pharmacology, and Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Jeanot Muster
- Howard Hughes Medical Institute, Department of Pharmacology, and Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Stephane Angers
- Howard Hughes Medical Institute, Department of Pharmacology, and Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Randall T. Moon
- Howard Hughes Medical Institute, Department of Pharmacology, and Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Benjamin N. R. Cheyette
- Department of Psychiatry, and Graduate Program in Developmental Biology, Program in Biological Sciences, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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Abstract
PAX5, a master regulator of B-cell development, was recently shown to be involved in several leukemia-associated rearrangements, which result in fusion genes encoding chimeric proteins that antagonize PAX5 transcriptional activity. In a population-based fluorescence in situ hybridization screening study of 446 childhood acute lymphoblastic leukemia (ALL) patients, we now show that PAX5 rearrangements occur at an incidence of about 2.5% of B-cell precursor ALL. Identification of several novel PAX5 partner genes, including POM121, BRD1, DACH1, HIPK1 and JAK2 brings the number of distinct PAX5 in-frame fusions to at least 12. Our data show that these not only comprise transcription factors but also structural proteins and genes involved in signal transduction, which at least in part have not been implicated in tumorigenesis.
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Puto LA, Reed JC. Daxx represses RelB target promoters via DNA methyltransferase recruitment and DNA hypermethylation. Genes Dev 2008; 22:998-1010. [PMID: 18413714 DOI: 10.1101/gad.1632208] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The apoptosis-modulating protein Daxx functions as a transcriptional repressor that binds to and suppresses the activity of nuclear factor-kappaB member RelB, among other transcription factors. The mechanism by which Daxx represses RelB target genes remains elusive. In this report, we demonstrate that Daxx controls epigenetic silencing of RelB target genes by DNA methylation. Daxx potently represses the RelB target genes dapk1, dapk3, c-flip, and birc3 (ciap2) at both the mRNA and protein levels. Recruitment of Daxx to target gene promoters, and its ability to repress them, is RelB-dependent, as shown by experiments using relB(-/-) cells. Importantly, methylation of target promoters is decreased in daxx(-/-) cells compared with daxx(+/+) cells, and stable transfection of daxx(-/-) cells with Daxx restores DNA methylation. Furthermore, Daxx recruits DNA methyl transferase 1 (Dnmt1) to target promoters, resulting in synergistic repression. The observation that Daxx functions to target DNA methyltransferases onto RelB target sites in the genome provides a rare example of a gene-specific mechanism for epigenetic silencing. Given the documented role of several of the RelB-regulated genes in diseases, particularly cancer, the findings have implications for developing therapeutic strategies based on epigenetic-modifying drugs.
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Affiliation(s)
- Lorena A Puto
- Program in Apoptosis and Cell Death Research, Burnham Institute for Medical Research, La Jolla, California 92037, USA
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Rinaldo C, Siepi F, Prodosmo A, Soddu S. HIPKs: Jack of all trades in basic nuclear activities. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1783:2124-9. [PMID: 18606197 DOI: 10.1016/j.bbamcr.2008.06.006] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 05/26/2008] [Accepted: 06/10/2008] [Indexed: 10/21/2022]
Abstract
Over the past decade several investigators have reported on the physical interaction of serine/threonine kinases of the homeodomain interacting-protein family (HIPKs) with increasing number of nuclear factors and on their localization in different nuclear sub-compartments. Although we are still far from a global understanding of the molecular consequences of HIPK subnuclear compartmentalization, the spatial description of particular interactions and posttranslational modifications promoted by these kinases on key cellular regulators might provide relevant insights. Here we will discuss the possible implications of the HIPK subnuclear localization in the regulation of gene transcription and in the cell response to stress.
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Affiliation(s)
- Cinzia Rinaldo
- Department of Experimental Oncology, Regina Elena Cancer Institute, 00158 Rome, Italy
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SENP1 mediates TNF-induced desumoylation and cytoplasmic translocation of HIPK1 to enhance ASK1-dependent apoptosis. Cell Death Differ 2008; 15:739-50. [DOI: 10.1038/sj.cdd.4402303] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Tavalai N, Papior P, Rechter S, Stamminger T. Nuclear domain 10 components promyelocytic leukemia protein and hDaxx independently contribute to an intrinsic antiviral defense against human cytomegalovirus infection. J Virol 2008; 82:126-37. [PMID: 17942542 PMCID: PMC2224380 DOI: 10.1128/jvi.01685-07] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Accepted: 10/10/2007] [Indexed: 12/28/2022] Open
Abstract
Infection with DNA viruses commonly results in the association of viral genomes with a cellular subnuclear structure known as nuclear domain 10 (ND10). Recent studies demonstrated that individual ND10 components, like hDaxx or promyelocytic leukemia protein (PML), mediate an intrinsic immune response against human cytomegalovirus (HCMV) infection, strengthening the assumption that ND10 components are part of a cellular antiviral defense mechanism. In order to further define the role of hDaxx and PML for HCMV replication, we generated either primary human fibroblasts with a stable, individual knockdown of PML or hDaxx (PML-kd and hDaxx-kd, respectively) or cells exhibiting a double knockdown. Comparative analysis of HCMV replication in PML-kd or hDaxx-kd cells revealed that immediate-early (IE) gene expression increased to a similar extent, regardless of which ND10 constituent was depleted. Since a loss of PML, the defining component of ND10, results in a dispersal of the entire nuclear substructure, the increased replication efficacy of HCMV in PML-kd cells could be a consequence of the dissociation of the repressor protein hDaxx from its optimal subnuclear localization. However, experiments using three different recombinant HCMVs revealed a differential growth complementation in PML-kd versus hDaxx-kd cells, strongly arguing for an independent involvement in suppressing HCMV replication. Furthermore, infection experiments using double-knockdown cells devoid of both PML and hDaxx illustrated an additional enhancement in the replication efficacy of HCMV compared to the single-knockdown cells. Taken together, our data indicate that both proteins, PML and hDaxx, mediate an intrinsic immune response against HCMV infection by contributing independently to the silencing of HCMV IE gene expression.
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Affiliation(s)
- Nina Tavalai
- Institut für Klinische und Molekulare Virologie, University Hospital Erlangen, Schlossgarten 4, 91054 Erlangen, Germany
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Arai S, Matsushita A, Du K, Yagi K, Okazaki Y, Kurokawa R. Novel homeodomain-interacting protein kinase family member, HIPK4, phosphorylates human p53 at serine 9. FEBS Lett 2007; 581:5649-57. [DOI: 10.1016/j.febslet.2007.11.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2007] [Revised: 11/02/2007] [Accepted: 11/04/2007] [Indexed: 11/28/2022]
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Benes FM, Lim B, Matzilevich D, Walsh JP, Subburaju S, Minns M. Regulation of the GABA cell phenotype in hippocampus of schizophrenics and bipolars. Proc Natl Acad Sci U S A 2007; 104:10164-9. [PMID: 17553960 PMCID: PMC1888575 DOI: 10.1073/pnas.0703806104] [Citation(s) in RCA: 391] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2007] [Indexed: 12/14/2022] Open
Abstract
GABAergic dysfunction is present in the hippocampus in schizophrenia (SZ) and bipolar disorder (BD). The trisynaptic pathway was "deconstructed" into various layers of sectors CA3/2 and CA1 and gene expression profiling performed. Network association analysis was used to uncover genes that may be related to regulation of glutamate decarboxylase 67 (GAD(67)), a marker for this system that has been found by many studies to show decreased expression in SZs and BDs. The most striking change was a down-regulation of GAD(67) in the stratum oriens (SO) of CA2/3 in both groups; CA1 only showed changes in the SO of schizophrenics. The network generated for GAD(67) contained 25 genes involved in the regulation of kainate receptors, TGF-beta and Wnt signaling, as well as transcription factors involved in cell growth and differentiation. In SZs, IL-1beta, (GRIK2/3), TGF-beta2, TGF-betaR1, histone deacetylase 1 (HDAC1), death associated protein (DAXX), and cyclin D2 (CCND2) were all significantly up-regulated, whereas in BDs, PAX5, Runx2, LEF1, TLE1, and CCND2 were significantly down-regulated. In the SO of CA1 of BDs, where GAD67 showed no expression change, TGF-beta and Wnt signaling genes were all up-regulated, but other transcription factors showed no change in expression. In other layers/sectors, BDs showed no expression changes in these GAD(67) network genes. Overall, these results are consistent with the hypothesis that decreased expression of GAD(67) may be associated with an epigenetic mechanism in SZ. In BD, however, a suppression of transcription factors involved in cell differentiation may contribute to GABA dysfunction.
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Affiliation(s)
- Francine M Benes
- Program in Structural and Molecular Neuroscience, McLean Hospital, Belmont, MA 02178, USA.
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50
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Lan HC, Li HJ, Lin G, Lai PY, Chung BC. Cyclic AMP stimulates SF-1-dependent CYP11A1 expression through homeodomain-interacting protein kinase 3-mediated Jun N-terminal kinase and c-Jun phosphorylation. Mol Cell Biol 2007; 27:2027-36. [PMID: 17210646 PMCID: PMC1820514 DOI: 10.1128/mcb.02253-06] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Steroids are synthesized in adrenal glands and gonads under the control of pituitary peptides. These peptides bind to cell surface receptors to activate the cyclic AMP (cAMP) signaling pathway leading to an increase of steroidogenic gene expression. Exactly how cAMP activates steroidogenic gene expression is not clear, except for the knowledge that transcription factor SF-1 plays a key role. Investigating the factors participating in SF-1 action, we found that c-Jun and homeodomain-interacting protein kinase 3 (HIPK3) were required for basal and cAMP-stimulated expression of one major steroidogenic gene, CYP11A1. HIPK3 enhanced SF-1 activity, and c-Jun was required for the functional interaction of HIPK3 with SF-1. Furthermore, after cAMP stimulation, both c-Jun and Jun N-terminal kinase (JNK) were phosphorylated through HIPK3. These phosphorylations were important for SF-1 activity and CYP11A1 expression. Thus, we have defined HIPK3-mediated JNK activity and c-Jun phosphorylation as important events that increase SF-1 activity for CYP11A1 transcription in response to cAMP. This finding has linked three common factors, HIPK3, JNK, and c-Jun, to the cAMP signaling pathway leading to increased steroidogenic gene expression.
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Affiliation(s)
- Hsin-Chieh Lan
- Institute of Molecular Biology, Academia Sinica, Nankang, Taipei 115, Taiwan
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