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Ruiling Z, Wenjuan L, Kexin Z, Xuejun W, Zhong Z. Developmental transcriptomics throughout the embryonic developmental process of Rhipicephalus turanicus reveals stage-specific gene expression profiles. Parasit Vectors 2022; 15:89. [PMID: 35292089 PMCID: PMC8922761 DOI: 10.1186/s13071-022-05214-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 02/20/2022] [Indexed: 11/10/2022] Open
Abstract
Background Ticks are important vectors and transmit diverse pathogens, including protozoa, viruses, and bacteria. Tick-borne diseases can cause damage to both human health and the livestock industries. The control and prevention of ticks and tick-borne diseases has relied heavily on acaricides. Methods In the present study, using a high-throughput RNA sequencing (RNA-Seq) technique, we performed a comprehensive time-series transcriptomic analysis throughout the embryogenesis period of Rhipicephalus turanicus. Results Altogether, 127,157 unigenes were assembled and clustered. Gene expression differences among the embryonic stages demonstrated that the most differentially expressed genes (DEGs) were observed in the comparisons of early embryonic stages (RTE5 vs. RTE10, 9726 genes), and there were far fewer DEGs in later stages (RTE25 vs. RTE30, 2751 genes). Furthermore, 16 distinct gene modules were identified according to weighted gene co-expression network analysis (WGCNA), and genes in different modules displayed stage-specific characteristics. Gene Ontology (GO) annotations and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment suggested that some genes involved in organ and tissue formation were significantly upregulated in the early embryonic developmental stages, whereas metabolism-related pathways were more enriched in the later embryonic developmental stages. Conclusions These transcriptome studies revealed gene expression profiles at different stages of embryonic development, which would be useful for interrupting the embryonic development of ticks and disrupting the transmission of tick-borne diseases. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-022-05214-w.
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Affiliation(s)
- Zhang Ruiling
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China. .,School of Basic Medical Sciences, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China.
| | - Liu Wenjuan
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China.,School of Basic Medical Sciences, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China
| | - Zhang Kexin
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China.,School of Basic Medical Sciences, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China
| | - Wang Xuejun
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China. .,Shandong Provincial Center for Disease Control and Prevention, Jinan, China.
| | - Zhang Zhong
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China. .,School of Basic Medical Sciences, Shandong First Medical University (Shandong Academy of Medical Sciences), Tai'an, China.
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2
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Wagstaff EL, Heredero Berzal A, Boon CJF, Quinn PMJ, ten Asbroek ALMA, Bergen AA. The Role of Small Molecules and Their Effect on the Molecular Mechanisms of Early Retinal Organoid Development. Int J Mol Sci 2021; 22:7081. [PMID: 34209272 PMCID: PMC8268497 DOI: 10.3390/ijms22137081] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/23/2021] [Accepted: 06/26/2021] [Indexed: 12/12/2022] Open
Abstract
Early in vivo embryonic retinal development is a well-documented and evolutionary conserved process. The specification towards eye development is temporally controlled by consecutive activation or inhibition of multiple key signaling pathways, such as the Wnt and hedgehog signaling pathways. Recently, with the use of retinal organoids, researchers aim to manipulate these pathways to achieve better human representative models for retinal development and disease. To achieve this, a plethora of different small molecules and signaling factors have been used at various time points and concentrations in retinal organoid differentiations, with varying success. Additions differ from protocol to protocol, but their usefulness or efficiency has not yet been systematically reviewed. Interestingly, many of these small molecules affect the same and/or multiple pathways, leading to reduced reproducibility and high variability between studies. In this review, we make an inventory of the key signaling pathways involved in early retinogenesis and their effect on the development of the early retina in vitro. Further, we provide a comprehensive overview of the small molecules and signaling factors that are added to retinal organoid differentiation protocols, documenting the molecular and functional effects of these additions. Lastly, we comparatively evaluate several of these factors using our established retinal organoid methodology.
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Affiliation(s)
- Ellie L. Wagstaff
- Department of Human Genetics, Amsterdam UMC, University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands;
| | - Andrea Heredero Berzal
- Department of Ophthalmology, Amsterdam UMC, University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands; (A.H.B.); (C.J.F.B.)
| | - Camiel J. F. Boon
- Department of Ophthalmology, Amsterdam UMC, University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands; (A.H.B.); (C.J.F.B.)
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZA Leiden, The Netherlands
| | - Peter M. J. Quinn
- Jonas Children’s Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Columbia Stem Cell Initiative, Departments of Ophthalmology, Pathology & Cell Biology, Institute of Human Nutrition, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA; Edward S. Harkness Eye Institute, Department of Ophthalmology, Columbia University Irving Medical Center—New York-Presbyterian Hospital, New York, NY 10032, USA;
| | | | - Arthur A. Bergen
- Department of Human Genetics, Amsterdam UMC, University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands;
- Department of Ophthalmology, Amsterdam UMC, University of Amsterdam (UvA), 1105 AZ Amsterdam, The Netherlands; (A.H.B.); (C.J.F.B.)
- Netherlands Institute for Neuroscience (NIN-KNAW), 1105 BA Amsterdam, The Netherlands
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3
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Patni AP, Harishankar MK, Joseph JP, Sreeshma B, Jayaraj R, Devi A. Comprehending the crosstalk between Notch, Wnt and Hedgehog signaling pathways in oral squamous cell carcinoma - clinical implications. Cell Oncol (Dordr) 2021; 44:473-494. [PMID: 33704672 DOI: 10.1007/s13402-021-00591-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 01/17/2021] [Accepted: 01/19/2021] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Oral squamous cell carcinoma (OSCC) is a malignant oral cavity neoplasm that affects many people, especially in developing countries. Despite several advances that have been made in diagnosis and treatment, the morbidity and mortality rates due to OSCC remain high. Accumulating evidence indicates that aberrant activation of cellular signaling pathways, such as the Notch, Wnt and Hedgehog pathways, occurs during the development and metastasis of OSCC. In this review, we have articulated the roles of the Notch, Wnt and Hedgehog signaling pathways in OSCC and their crosstalk during tumor development and progression. We have also examined possible interactions and associations between these pathways and treatment regimens that could be employed to effectively tackle OSCC and/or prevent its recurrence. CONCLUSIONS Activation of the Notch signaling pathway upregulates the expression of several genes, including c-Myc, β-catenin, NF-κB and Shh. Associations between the Notch signaling pathway and other pathways have been shown to enhance OSCC tumor aggressiveness. Crosstalk between these pathways supports the maintenance of cancer stem cells (CSCs) and regulates OSCC cell motility. Thus, application of compounds that block these pathways may be a valid strategy to treat OSCC. Such compounds have already been employed in other types of cancer and could be repurposed for OSCC.
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Affiliation(s)
- Anjali P Patni
- Stem Cell Biology Laboratory, Department of Genetic Engineering, School of Bioengineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kanchipuram, Kattankulathur, Chennai, Tamil Nadu, 603203, India
| | - M K Harishankar
- Stem Cell Biology Laboratory, Department of Genetic Engineering, School of Bioengineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kanchipuram, Kattankulathur, Chennai, Tamil Nadu, 603203, India
| | - Joel P Joseph
- Stem Cell Biology Laboratory, Department of Genetic Engineering, School of Bioengineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kanchipuram, Kattankulathur, Chennai, Tamil Nadu, 603203, India
| | - Bhuvanadas Sreeshma
- Stem Cell Biology Laboratory, Department of Genetic Engineering, School of Bioengineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kanchipuram, Kattankulathur, Chennai, Tamil Nadu, 603203, India
| | - Rama Jayaraj
- College of Human and Human Sciences, Charles Darwin University, Ellangowan Drive, Darwin, Northern Territory, 0909, Australia
| | - Arikketh Devi
- Stem Cell Biology Laboratory, Department of Genetic Engineering, School of Bioengineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kanchipuram, Kattankulathur, Chennai, Tamil Nadu, 603203, India.
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4
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Li H, Wang W, Zhang W, Wu G. Structural insight into the recognition between Sufu and fused in the Hedgehog signal transduction pathway. J Struct Biol 2020; 212:107614. [PMID: 32911070 DOI: 10.1016/j.jsb.2020.107614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/15/2020] [Accepted: 09/02/2020] [Indexed: 10/23/2022]
Abstract
Hedgehog signaling plays a crucial role in embryogenesis and adult tissue homeostasis, and mutations of its key components such as Suppressor of fused (Sufu) are closely associated with human diseases. The Ser/Thr kinase Fused (Fu) promotes Hedgehog signaling by phosphorylating the Cubitus interruptus (Ci)/Glioma-associated oncogene homologue (Gli) family of transcription factors. Sufu associates with both Fu and Ci/Gli, but the recognition mechanism between Sufu and Fu remains obscure. Here, our structure of the N-terminal domain (NTD) of Drosophila Sufu (dSufu) in complex with the Sufu-binding site (SBS) of Fu reveals that both main-chain β sheet formation and side-chain hydrophobic interactions contribute to the recognition between Sufu and Fu, and point mutations of highly conserved interface residues eliminated their association. Structural comparison suggests that Fu and Ci/Gli bind on opposite sides of dSufu-NTD, allowing the formation of a Fu-dSufu-Ci ternary complex which facilitates the phosphorylation of Ci/Gli by Fu. Hence, our results provide insights into the Sufu-Fu recognition mechanism.
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Affiliation(s)
- Hua Li
- State Key Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai, China
| | - Wen Wang
- State Key Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai, China
| | - Wei Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai, China
| | - Geng Wu
- State Key Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai, China.
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5
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Scheidt T, Alka O, Gonczarowska-Jorge H, Gruber W, Rathje F, Dell’Aica M, Rurik M, Kohlbacher O, Zahedi RP, Aberger F, Huber CG. Phosphoproteomics of short-term hedgehog signaling in human medulloblastoma cells. Cell Commun Signal 2020; 18:99. [PMID: 32576205 PMCID: PMC7310537 DOI: 10.1186/s12964-020-00591-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 05/05/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Aberrant hedgehog (HH) signaling is implicated in the development of various cancer entities such as medulloblastoma. Activation of GLI transcription factors was revealed as the driving force upon pathway activation. Increased phosphorylation of essential effectors such as Smoothened (SMO) and GLI proteins by kinases including Protein Kinase A, Casein Kinase 1, and Glycogen Synthase Kinase 3 β controls effector activity, stability and processing. However, a deeper and more comprehensive understanding of phosphorylation in the signal transduction remains unclear, particularly during early response processes involved in SMO activation and preceding GLI target gene regulation. METHODS We applied temporal quantitative phosphoproteomics to reveal phosphorylation dynamics underlying the short-term chemical activation and inhibition of early hedgehog signaling in HH responsive human medulloblastoma cells. Medulloblastoma cells were treated for 5.0 and 15 min with Smoothened Agonist (SAG) to induce and with vismodegib to inhibit the HH pathway. RESULTS Our phosphoproteomic profiling resulted in the quantification of 7700 and 10,000 phosphosites after 5.0 and 15 min treatment, respectively. The data suggest a central role of phosphorylation in the regulation of ciliary assembly, trafficking, and signal transduction already after 5.0 min treatment. ERK/MAPK signaling, besides Protein Kinase A signaling and mTOR signaling, were differentially regulated after short-term treatment. Activation of Polo-like Kinase 1 and inhibition of Casein Kinase 2A1 were characteristic for vismodegib treatment, while SAG treatment induced Aurora Kinase A activity. Distinctive phosphorylation of central players of HH signaling such as SMO, SUFU, GLI2 and GLI3 was observed only after 15 min treatment. CONCLUSIONS This study provides evidence that phosphorylation triggered in response to SMO modulation dictates the localization of hedgehog pathway components within the primary cilium and affects the regulation of the SMO-SUFU-GLI axis. The data are relevant for the development of targeted therapies of HH-associated cancers including sonic HH-type medulloblastoma. A deeper understanding of the mechanisms of action of SMO inhibitors such as vismodegib may lead to the development of compounds causing fewer adverse effects and lower frequencies of drug resistance. Video Abstract.
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Affiliation(s)
- Tamara Scheidt
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
| | - Oliver Alka
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - Humberto Gonczarowska-Jorge
- Leibniz-Institute of Analytical Sciences- ISAS - e.V, Dortmund, Germany
- Present address: CAPES Foundation, Ministry of Education of Brazil, Brasília, DF 70040-020 Brazil
| | - Wolfgang Gruber
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
- Present address: EVER Valinject GmbH, 4866 Unterach am Attersee, Austria
| | - Florian Rathje
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
| | | | - Marc Rurik
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - Oliver Kohlbacher
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
- Biomolecular Interactions, Max Planck Institute for Developmental Biology, Max-Planck-Ring 5, 72076 Tübingen, Germany
- Institute for Translational Bioinformatics, University Hospital Tübingen, Hoppe-Seyler-Str. 9, 72076 Tübingen, Germany
- Applied Bioinformatics, Center for Bioinformatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - René P. Zahedi
- Leibniz-Institute of Analytical Sciences- ISAS - e.V, Dortmund, Germany
- Gerald Bronfman Department of Oncology, Jewish General Hospital, McGill University, Montreal, Canada
- Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, Canada
| | - Fritz Aberger
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
| | - Christian G. Huber
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
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6
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Peer E, Tesanovic S, Aberger F. Next-Generation Hedgehog/GLI Pathway Inhibitors for Cancer Therapy. Cancers (Basel) 2019; 11:cancers11040538. [PMID: 30991683 PMCID: PMC6520835 DOI: 10.3390/cancers11040538] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/04/2019] [Accepted: 04/09/2019] [Indexed: 12/26/2022] Open
Abstract
The Hedgehog/Glioma-associated oncogene homolog (HH/GLI) signaling pathway regulates self-renewal of rare and highly malignant cancer stem cells (CSC), which have been shown to account for the initiation and maintenance of tumor growth as well as for drug resistance, metastatic spread and relapse. Efficacious therapeutic approaches targeting CSC pathways, such as HH/GLI signaling in combination with chemo, radiation or immunotherapy are, therefore, of high medical need. Pharmacological inhibition of HH/GLI pathway activity represents a promising approach to eliminate malignant CSC. Clinically approved HH/GLI pathway inhibitors target the essential pathway effector Smoothened (SMO) with striking therapeutic efficacy in skin and brain cancer patients. However, multiple genetic and molecular mechanisms resulting in de novo and acquired resistance to SMO inhibitors pose major limitations to anti-HH/GLI therapies and, thus, the eradication of CSC. In this review, we summarize reasons for clinical failure of SMO inhibitors, including mechanisms caused by genetic alterations in HH pathway effectors or triggered by additional oncogenic signals activating GLI transcription factors in a noncanonical manner. We then discuss emerging novel and rationale-based approaches to overcome SMO-inhibitor resistance, focusing on pharmacological perturbations of enzymatic modifiers of GLI activity and on compounds either directly targeting oncogenic GLI factors or interfering with synergistic crosstalk signals known to boost the oncogenicity of HH/GLI signaling.
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Affiliation(s)
- Elisabeth Peer
- Department of Biosciences, Paris-Lodron University of Salzburg, Cancer Cluster Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria.
| | - Suzana Tesanovic
- Department of Biosciences, Paris-Lodron University of Salzburg, Cancer Cluster Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria.
| | - Fritz Aberger
- Department of Biosciences, Paris-Lodron University of Salzburg, Cancer Cluster Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria.
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7
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Giordano C, Ruel L, Poux C, Therond P. Protein association changes in the Hedgehog signaling complex mediate differential signaling strength. Development 2018; 145:145/24/dev166850. [PMID: 30541874 DOI: 10.1242/dev.166850] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 11/07/2018] [Indexed: 01/20/2023]
Abstract
Hedgehog (Hh) is a conserved morphogen that controls cell differentiation and tissue patterning in metazoans. In Drosophila, the Hh signal is transduced from the G protein-coupled receptor Smoothened (Smo) to the cytoplasmic Hh signaling complex (HSC). How activated Smo is translated into a graded activation of the downstream pathway is still not well understood. In this study, we show that the last amino acids of the cytoplasmic tail of Smo, in combination with G protein-coupled receptor kinase 2 (Gprk2), bind to the regulatory domain of Fused (Fu) and highly activate its kinase activity. We further show that this binding induces changes in the association of Fu protein with the HSC and increases the proximity of the Fu catalytic domain to its substrate, the Costal2 kinesin. We propose a new model in which, depending on the magnitude of Hh signaling, Smo and Gprk2 modulate protein association and conformational changes in the HSC, which are responsible for the differential activation of the pathway.
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Affiliation(s)
- Cecile Giordano
- Université Côte d'Azur, CNRS, Inserm, iBV, 06108 Nice, France
| | - Laurent Ruel
- Université Côte d'Azur, CNRS, Inserm, iBV, 06108 Nice, France
| | - Candice Poux
- Stockholms Universitet, Wenner-Grens Institut, SE-106 91 Stockholm, Sweden
| | - Pascal Therond
- Université Côte d'Azur, CNRS, Inserm, iBV, 06108 Nice, France
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8
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Lv X, Chen H, Zhang S, Zhang Z, Pan C, Xia Y, Fan J, Wu W, Lu Y, Zhang L, Wu H, Zhao Y. Fsh-Pc-Sce complex mediates active transcription of Cubitus interruptus (Ci). J Mol Cell Biol 2018; 10:437-447. [PMID: 29432547 DOI: 10.1093/jmcb/mjy008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 02/07/2018] [Indexed: 12/30/2022] Open
Abstract
The Hedgehog (Hh) signaling pathway plays important roles in both embryonic development and adult tissue homeostasis. Such biological functions are mediated by the transcription factor Cubitus interruptus (Ci). Yet the transcriptional regulation of the effector Ci itself is poorly investigated. Through an RNAi-based genetic screen, we identified that female sterile (1) homeotic (Fsh), a transcription co-activator, directly activates Ci transcription. Biochemistry assays demonstrated physical interactions among Fsh, Sex combs extra (Sce), and Polycomb (Pc). Functional assays further showed that both Pc and Sce are required for Ci expression, which is not likely mediated by the derepression of Engrailed (En), a repressor of Ci, in Pc or Sce mutant cells. Finally, we provide evidence showing that Pc/Sce facilitates the binding of Fsh at Ci locus and that the physical interaction between Fsh and Pc is essential for Fsh-mediated Ci transcription. Taken together, we not only uncover that Ci is transcriptionally regulated by Fsh-Pc-Sce complex but also provide evidence for the coordination between Fsh and PcG proteins in transcriptional regulation.
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Affiliation(s)
- Xiangdong Lv
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Hao Chen
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Shuo Zhang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Zhao Zhang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Chenyu Pan
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Yuanxin Xia
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Jialin Fan
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Wenqing Wu
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Yi Lu
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Lei Zhang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Hailong Wu
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Yun Zhao
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China
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9
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Yue Y, Blasius TL, Zhang S, Jariwala S, Walker B, Grant BJ, Cochran JC, Verhey KJ. Altered chemomechanical coupling causes impaired motility of the kinesin-4 motors KIF27 and KIF7. J Cell Biol 2018; 217:1319-1334. [PMID: 29351996 PMCID: PMC5881503 DOI: 10.1083/jcb.201708179] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/28/2017] [Accepted: 01/02/2018] [Indexed: 01/08/2023] Open
Abstract
Kinesin-4 motors play important roles in cell division, microtubule organization, and signaling. Understanding how motors perform their functions requires an understanding of their mechanochemical and motility properties. We demonstrate that KIF27 can influence microtubule dynamics, suggesting a conserved function in microtubule organization across the kinesin-4 family. However, kinesin-4 motors display dramatically different motility characteristics: KIF4 and KIF21 motors are fast and processive, KIF7 and its Drosophila melanogaster homologue Costal2 (Cos2) are immotile, and KIF27 is slow and processive. Neither KIF7 nor KIF27 can cooperate for fast processive transport when working in teams. The mechanistic basis of immotile KIF7 behavior arises from an inability to release adenosine diphosphate in response to microtubule binding, whereas slow processive KIF27 behavior arises from a slow adenosine triphosphatase rate and a high affinity for both adenosine triphosphate and microtubules. We suggest that evolutionarily selected sequence differences enable immotile KIF7 and Cos2 motors to function not as transporters but as microtubule-based tethers of signaling complexes.
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Affiliation(s)
- Yang Yue
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - T Lynne Blasius
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - Stephanie Zhang
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN
| | - Shashank Jariwala
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI
| | - Benjamin Walker
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN
| | - Barry J Grant
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI
| | - Jared C Cochran
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN
| | - Kristen J Verhey
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
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10
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Zhao L, Wang L, Chi C, Lan W, Su Y. The emerging roles of phosphatases in Hedgehog pathway. Cell Commun Signal 2017; 15:35. [PMID: 28931407 PMCID: PMC5607574 DOI: 10.1186/s12964-017-0191-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 09/14/2017] [Indexed: 01/12/2023] Open
Abstract
Hedgehog signaling is evolutionarily conserved and plays a pivotal role in cell fate determination, embryonic development, and tissue renewal. As aberrant Hedgehog signaling is tightly associated with a broad range of human diseases, its activities must be precisely controlled. It has been known that several core components of Hedgehog pathway undergo reversible phosphorylations mediated by protein kinases and phosphatases, which acts as an effective regulatory mechanism to modulate Hedgehog signal activities. In contrast to kinases that have been extensively studied in these phosphorylation events, phosphatases were thought to function in an unspecific manner, thus obtained much less emphasis in the past. However, in recent years, increasing evidence has implicated that phosphatases play crucial and specific roles in the context of developmental signaling, including Hedgehog signaling. In this review, we present a summary of current progress on phosphatase studies in Hedgehog pathway, emphasizing the multiple employments of protein serine/threonine phosphatases during the transduction of morphogenic Hedgehog signal in both Drosophila and vertebrate systems, all of which provide insights into the importance of phosphatases in the specific regulation of Hedgehog signaling.
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Affiliation(s)
- Long Zhao
- Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, 02129, USA
| | - Liguo Wang
- Institute of Evolution & Marine Biodiversity, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Chunli Chi
- Institute of Evolution & Marine Biodiversity, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Wenwen Lan
- Institute of Evolution & Marine Biodiversity, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Ying Su
- Institute of Evolution & Marine Biodiversity, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China.
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11
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Li T, Fan J, Blanco-Sánchez B, Giagtzoglou N, Lin G, Yamamoto S, Jaiswal M, Chen K, Zhang J, Wei W, Lewis MT, Groves AK, Westerfield M, Jia J, Bellen HJ. Ubr3, a Novel Modulator of Hh Signaling Affects the Degradation of Costal-2 and Kif7 through Poly-ubiquitination. PLoS Genet 2016; 12:e1006054. [PMID: 27195754 PMCID: PMC4873228 DOI: 10.1371/journal.pgen.1006054] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Accepted: 04/25/2016] [Indexed: 12/21/2022] Open
Abstract
Hedgehog (Hh) signaling regulates multiple aspects of metazoan development and tissue homeostasis, and is constitutively active in numerous cancers. We identified Ubr3, an E3 ubiquitin ligase, as a novel, positive regulator of Hh signaling in Drosophila and vertebrates. Hh signaling regulates the Ubr3-mediated poly-ubiquitination and degradation of Cos2, a central component of Hh signaling. In developing Drosophila eye discs, loss of ubr3 leads to a delayed differentiation of photoreceptors and a reduction in Hh signaling. In zebrafish, loss of Ubr3 causes a decrease in Shh signaling in the developing eyes, somites, and sensory neurons. However, not all tissues that require Hh signaling are affected in zebrafish. Mouse UBR3 poly-ubiquitinates Kif7, the mammalian homologue of Cos2. Finally, loss of UBR3 up-regulates Kif7 protein levels and decreases Hh signaling in cultured cells. In summary, our work identifies Ubr3 as a novel, evolutionarily conserved modulator of Hh signaling that boosts Hh in some tissues.
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Affiliation(s)
- Tongchao Li
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Junkai Fan
- Markey Cancer Center and Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
| | | | - Nikolaos Giagtzoglou
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
| | - Guang Lin
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Shinya Yamamoto
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
| | - Manish Jaiswal
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas, United States of America
| | - Kuchuan Chen
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jie Zhang
- Markey Cancer Center and Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
| | - Wei Wei
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Michael T. Lewis
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Andrew K. Groves
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
| | - Monte Westerfield
- Institute of Neuroscience, University of Oregon, Eugene, Oregon, United States of America
| | - Jianhang Jia
- Markey Cancer Center and Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
| | - Hugo J. Bellen
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
- * E-mail:
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12
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Abstract
The Hedgehog (Hh) signaling pathway play critical roles in embryonic development and adult tissue homeostasis. A critical step in Hh signal transduction is how Hh receptor Patched (Ptc) inhibits the atypical G protein-coupled receptor Smoothened (Smo) in the absence of Hh and how this inhibition is release by Hh stimulation. It is unlikely that Ptc inhibits Smo by direct interaction. Here we discuss how Hh regulates the phosphorylation and ubiquitination of Smo, leading to cell surface and ciliary accumulation of Smo in Drosophila and vertebrate cells, respectively. In addition, we discuss how PI(4)P phospholipid acts in between Ptc and Smo to regulate Smo phosphorylation and activation in response to Hh stimulation.
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Affiliation(s)
- Kai Jiang
- Markey Cancer Center, Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Jianhang Jia
- Markey Cancer Center, Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
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13
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Vedanayagam JP, Garrigan D. The effects of natural selection across molecular pathways in Drosophila melanogaster. BMC Evol Biol 2015; 15:203. [PMID: 26391223 PMCID: PMC4578789 DOI: 10.1186/s12862-015-0472-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/30/2015] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Whole-genome RNA interference post-transcriptional silencing (RNAi) is a widely used method for studying the phenotypic effects of knocking down individual genes. In this study, we use a population genomic approach to characterize the rate of evolution for proteins affecting 26 RNAi knockdown phenotypes in Drosophila melanogaster. RESULTS We find that only two of the 26 RNAi knockdown phenotypes are enriched for rapidly evolving proteins: innate immunity and regulation of Hedgehog signaling. Among all genes associated with an RNAi knockdown phenotype, we note examples in which the adaptively evolving proteins play a well-defined role in a given molecular pathway. However, most adaptively evolving proteins are found to perform more general cellular functions. When RNAi phenotypes are grouped into categories according to cellular function, we find that genes involved in the greatest number of phenotypic categories are also significantly more likely to have a history of rapid protein evolution. CONCLUSIONS We show that genes that have been demonstrated to have a measurable effect on multiple molecular phenotypes show higher rates of protein evolution than genes having an effect on a single category of phenotype. Defining pleiotropy in this way yields very different results than previous studies that define pleiotropy by the number of physical interactions, which show highly connected proteins tend to evolve more slowly than lowly connected proteins. We suggest that a high degree of pleiotropy may increase the likelihood of compensatory substitution, consistent with modern theoretical work on adaptation.
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Affiliation(s)
| | - Daniel Garrigan
- Department of Biology, University of Rochester, Rochester, New York, 14627, USA.
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14
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Suh HN, Han HJ. Sonic hedgehog increases the skin wound-healing ability of mouse embryonic stem cells through the microRNA 200 family. Br J Pharmacol 2014; 172:815-28. [PMID: 25257936 DOI: 10.1111/bph.12947] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 09/03/2014] [Accepted: 09/13/2014] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND AND PURPOSE To use stem cell therapy effectively, it is important to enhance the therapeutic potential of stem cells with soluble factors. Although sonic hedgehog (shh) is important in maintaining the stem cell, the recovery effect of mouse embryonic stem cells (mESCs) with shh has not yet been elucidated. The present study investigated the effect of mESCs with shh in skin recovery in vivo as well as the related intracellular signal pathways in vitro. EXPERIMENTAL APPROACH The healing effect of mESCs with shh on skin wounds was examined in vivo in ICR mice. The involvement of Smads, the microRNA (miR)-200 family, zinc finger E-box-binding homeobox (ZEBs) and E-cadherin on shh-induced mESC migration and self-renewal was determined in vitro. KEY RESULTS The mESCs with shh increased re-epithelialization and VEGF expression in skin wounds. Shh-treated mESCs increased both secreted and intracellular levels of VEGF. Shh induced dephosphorylation of glycogen synthase kinase 3β through the Smoothened receptor and increased the phosphorylation of Smad1 and Smad2/3 in mESCs. Shh-induced decrease of the mmu-miR-141, -200c, -200a, -200b and -429 expression levels was significantly reversed by Smad4 siRNA. Shh increased nuclear expression of ZEB1/ZEB2 and decreased E-cadherin expression while increasing cell migration and skin wound healing. Both these effects were reversed by mmu-miR-141 and -200b mimics. CONCLUSIONS AND IMPLICATIONS Mouse ESCs accelerated skin wound healing by shh through down-regulating E-cadherin, an effect dependent on mmu-miR-141 and -200b. Our data provides evidence for the effectiveness of shh in stem cell-based therapy in vivo.
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Affiliation(s)
- Han Na Suh
- Department of Veterinary Physiology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
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15
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Zhang Y, Dong W, Guo S, Zhao S, He S, Zhang L, Tang Y, Wang H. Lentivirus-mediated delivery of sonic hedgehog into the striatum stimulates neuroregeneration in a rat model of Parkinson disease. Neurol Sci 2014; 35:1931-40. [PMID: 25030123 DOI: 10.1007/s10072-014-1866-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 06/25/2014] [Indexed: 12/14/2022]
Abstract
Parkinson disease (PD) is a progressive neurodegenerative disorder in which the nigrostriatal pathway, consisting of dopaminergic neuronal projections from the substantia nigra to the striatum, degenerates. Viral transduction is currently the most promising in vivo strategy for delivery of therapeutic proteins into the brain for treatment of PD. Sonic hedgehog (Shh) is necessary for cell proliferation, differentiation and neuroprotection in the central nervous system. In this study, we investigated the effects of overexpressed N-terminal product of SHH (SHH-N) in a PD model rat. A lentiviral vector containing SHH-N was stereotactically injected into the striatum 24 h after a striatal 6-OHDA lesion. We found that overexpressed SHH-N attenuated behavioral deficits and reduced the loss of dopamine neurons in the substantia nigra and the loss of dopamine fibers in the striatum. In addition, fluoro-ruby-labeled nigrostriatal projections were also repaired. Together, our results demonstrate the feasibility and efficacy of using the strategy of lentivirus-mediated Shh-N delivery to delay nigrostriatal pathway degeneration. This strategy holds the potential for therapeutic application in the treatment of PD.
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Affiliation(s)
- Yi Zhang
- Department of Gynecology and Obstetrics, The Third Affiliated Hospital of Southern Medical University, Guangzhou, 510630, Guangdong, China
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16
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Mbodj A, Junion G, Brun C, Furlong EEM, Thieffry D. Logical modelling of Drosophila signalling pathways. MOLECULAR BIOSYSTEMS 2014; 9:2248-58. [PMID: 23868318 DOI: 10.1039/c3mb70187e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A limited number of signalling pathways are involved in the specification of cell fate during the development of all animals. Several of these pathways were originally identified in Drosophila. To clarify their roles, and possible cross-talk, we have built a logical model for the nine key signalling pathways recurrently used in metazoan development. In each case, we considered the associated ligands, receptors, signal transducers, modulators, and transcription factors reported in the literature. Implemented using the logical modelling software GINsim, the resulting models qualitatively recapitulate the main characteristics of each pathway, in wild type as well as in various mutant situations (e.g. loss-of-function or gain-of-function). These models constitute pluggable modules that can be used to assemble comprehensive models of complex developmental processes. Moreover, these models of Drosophila pathways could serve as scaffolds for more complicated models of orthologous mammalian pathways. Comprehensive model annotations and GINsim files are provided for each of the nine considered pathways.
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Affiliation(s)
- Abibatou Mbodj
- Technological Advances for Genomics and Clinics (TAGC), INSERM UMR_S 1090, Aix-Marseille Université, Marseille, France.
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17
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Dimitrova K, Stoehr M, Dehghani F, Dietz A, Wichmann G, Bertolini J, Mozet C. Overexpression of the Hedgehog signalling pathway in head and neck squamous cell carcinoma. ACTA ACUST UNITED AC 2013; 36:279-86. [PMID: 23689223 DOI: 10.1159/000350322] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Overexpression of the Hedgehog (HH) signalling pathway has been described in several malignancies and is associated with a poor prognosis. HH signalling blockade reduces tumour growth in vitro and in vivo. We aimed to determine whether head and neck squamous cell carcinomas (HNSCCs) express HH proteins in comparison to healthy mucosa. PATIENTS AND METHODS Formalin-fixed and paraffin-embedded tissue sections of 10 patients with HNSCC were stained with fluorescence-labelled antibodies for cytokeratin and HH proteins (SHH, PTCH1/2, SMO, Gli1-3) and photographs were taken with a laser scanning microscope. The pixel count and colour intensity were analysed in RGB (red/green/blue) colour mode, and expression levels were compared to healthy mucosa. RESULTS Image analysis in RGB mode provided objective evidence for the over-expression of HH signalling components in HNSCC, particularly with regard to the transcription factors Gli1 (10-fold) and SHH (5-fold) in comparison with healthy mucosa. The lowest levels were found for Gli3 in HNSCC. CONCLUSIONS We postulate pivotal roles of Gli1 and SHH expression in the carcinogenesis of HNSCC. HH pathway overexpression appears to be involved in the initiation of tumour growth and spread due to its stem cell-modulating properties. Detection of HH pathway components, and especially Gli1 and SHH, in HNSCC might offer a promising target for further anticancer research in HNSCC.
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Affiliation(s)
- Kamelia Dimitrova
- Department of Otolaryngology, Head and Neck Surgery, University of Leipzig, Germany
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18
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Zhang Y, Zhao S, Dong W, He S, Wang H, Zhang L, Tang Y, Guo J, Guo S. Cloning and bioinformatical analysis of the N-terminus of the sonic hedgehog gene. Neural Regen Res 2013; 8:258-63. [PMID: 25206596 PMCID: PMC4107527 DOI: 10.3969/j.issn.1673-5374.2013.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 10/26/2012] [Indexed: 11/18/2022] Open
Abstract
The sonic hedgehog protein not only plays a key role in early embryonic development, but also has essential effects on the adult nervous system, including neural stem cell proliferation, differentiation, migration and neuronal axon guidance. The N-terminal fragment of sonic hedgehog is the key functional element in this process. Therefore, this study aimed to clone and analyze the N-terminal fragment of the sonic hedgehog gene. Total RNA was extracted from the notochord of a Sprague-Dawley rat at embryonic day 9 and the N-terminal fragment of sonic hedgehog was amplified by nested reverse transcription-PCR. The N-terminal fragment of the sonic hedgehog gene was successfully cloned. The secondary and tertiary structures of the N-terminal fragment of the sonic hedgehog protein were predicted using Jpred and Phyre online.
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Affiliation(s)
- Yi Zhang
- School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, Guangdong Province, China ; Department of Gynecology and Obstetrics, the Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, Guangdong Province, China
| | - Shu Zhao
- School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, Guangdong Province, China
| | - Weiren Dong
- School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, Guangdong Province, China
| | - Suifen He
- Department of Laboratory, Shunde Guizhou Hospital, Foshan 528305, Guangdong Province, China
| | - Haihong Wang
- School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, Guangdong Province, China
| | - Lihua Zhang
- School of Medical Sciences, Foshan University, Foshan 528000, Guangdong Province, China
| | - Yinjuan Tang
- Department of Histology & Embryology, Xiangnan College, Chenzhou 418000, Hunan Province, China
| | - Jiasong Guo
- Department of Gynecology and Obstetrics, the Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, Guangdong Province, China
| | - Suiqun Guo
- Department of Gynecology and Obstetrics, the Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, Guangdong Province, China
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19
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Maixner DW, Weng HR. The Role of Glycogen Synthase Kinase 3 Beta in Neuroinflammation and Pain. ACTA ACUST UNITED AC 2013; 1:001. [PMID: 25309941 DOI: 10.13188/2327-204x.1000001] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Neuroinflammation is a crucial mechanism related to many neurological diseases. Extensive studies in recent years have indicated that dysregulation of Glycogen Synthase Kinase 3 Beta (GSK3β) contributes to the development and progression of these disorders through regulating the neuroinflammation processes. Inhibitors of GSK3β have been shown to be beneficial in many neuroinflammatory disease models including Alzheimer's disease, multiple sclerosis and AIDS dem entia complex. Glial activation and elevated pro-inflammation cytokines (signs of neuroinflammation) in the spinal cord have been widely recognized as a pivotal mechanism underlying the development and maintenance of many types of pathological pain. The role of GSK3β in the pathogenesis of pain has recently emerged. In this review, we will first review the GSK3β structure, regulation, and mechanisms by which GSK3βregulates inflammation. We will then describe neuroinflammationin general and in specific types of neurological diseases and the potential beneficial effects induced by inhibiting GSK3β. Finally, we will provide new evidence linking aberrant levels of GSK3β in the development of pathological pain.
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Affiliation(s)
- Dylan Warren Maixner
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia, 30606, USA
| | - Han-Rong Weng
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia, 30606, USA
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20
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Seifert K, Büttner A, Rigol S, Eilert N, Wandel E, Giannis A. Potent small molecule Hedgehog agonists induce VEGF expression in vitro. Bioorg Med Chem 2012; 20:6465-81. [DOI: 10.1016/j.bmc.2012.08.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 08/17/2012] [Accepted: 08/20/2012] [Indexed: 12/21/2022]
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21
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Queiroz KCS, Spek CA, Peppelenbosch MP. Targeting Hedgehog signaling and understanding refractory response to treatment with Hedgehog pathway inhibitors. Drug Resist Updat 2012; 15:211-22. [PMID: 22910179 DOI: 10.1016/j.drup.2012.05.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Revised: 05/25/2012] [Accepted: 05/26/2012] [Indexed: 12/01/2022]
Abstract
Hedgehog (Hh) signaling is a principal component of the morphogenetic code best known to direct pattern formation during embryogenesis. The Hh pathway remains active in adulthood however where it guides tissue regeneration and remodeling and Hh production in the niche plays an important role in maintaining stem cell compartment size. Deregulated Hh signaling activity is associated, depending on the context, with both cancer initiation and progression. Interestingly, the Hh pathway is remarkably druggable, raising hopes that inhibition of the pathway could support anticancer therapy. Indeed, a large body of preclinical data supports such an action, but promising clinical data are still limited to basal cell carcinoma (BSC) and medulloblastoma. Nevertheless cancer resistance against Hh targeting has already emerged as a major problem. Here we shall review the current situation with respect to targeting the Hh pathway in cancer in general and in chemotolerance in particular with a focus on the problems associated with the emergence of tumors resistant to treatment with inhibitors targeting the Hh receptor Smoothened (SMO).
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Affiliation(s)
- Karla C S Queiroz
- Center for Experimental and Molecular Medicine, Academic Medical Center, University of Amsterdam, The Netherlands
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22
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Li J, Xu Y, Chong K. The novel functions of kinesin motor proteins in plants. PROTOPLASMA 2012; 249 Suppl 2:S95-100. [PMID: 22167300 PMCID: PMC3389602 DOI: 10.1007/s00709-011-0357-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 11/28/2011] [Indexed: 05/17/2023]
Abstract
Kinesin superfamily proteins are important microtubule-based motor proteins with a kinesin motor domain that is conserved among all eukaryotic organisms. They are responsible for unidirectionally transporting various cargoes, including membranous organelles, protein complexes, and mRNAs. They also play critical roles in mitosis, morphogenesis, and signal transduction. Most kinesins in plants are evolutionarily divergent from their counterparts in animals and fungi. The mitotic kinesins in the plant kinesin-5 and kinesin-14 subfamilies appear to be similar to those in fungi and animals. However, others with nonmotor sequences are unique to plants. The kinesins affect microtubule organization, organelle distribution, vesicle transport, and cellulose microfibril order. Ultimately, plant kinesins contribute directly or indirectly to cell division and cell growth in various tissues. Here, we review a novel function of kinesins with transcription activation activity in regulating gibberellin biosynthesis and cell growth. These findings will open exciting new areas of kinesin research.
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Affiliation(s)
- Juan Li
- Research Center for Molecular and Developmental Biology, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093 China
| | - Yunyuan Xu
- Research Center for Molecular and Developmental Biology, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093 China
| | - Kang Chong
- Research Center for Molecular and Developmental Biology, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093 China
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23
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Hh-induced Smoothened conformational switch is mediated by differential phosphorylation at its C-terminal tail in a dose- and position-dependent manner. Dev Biol 2012; 366:172-84. [PMID: 22537496 DOI: 10.1016/j.ydbio.2012.04.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 04/02/2012] [Accepted: 04/07/2012] [Indexed: 12/26/2022]
Abstract
The activation of Smoothened (Smo) requires phosphorylation at three clusters of Serine residues in Drosophila Hedgehog (Hh) signaling. However, the mechanism by which phosphorylation promotes Smo conformational change and subsequently activates Smo in response to Hh gradient remains unclear. Here, we show that the conformational states of Smo are determined by not only the amount but also the position of the negative charges provided by phosphorylation. By using a Smo phospho-specific antibody, we demonstrate that Smo is differentially phosphorylated at three clusters of serine residues in response to levels of Hh activity. Mutating the first cluster, compared to mutating the other clusters, impairs Smo activity more severely, whereas mutating the last cluster prohibits C-terminus dimerization. In addition, phosphorylation of the membrane proximal cluster promotes phosphorylation of the distal cluster. We propose a zipper-lock model in which the gradual phosphorylation at these clusters induces a gradual conformational change in the Smo cytoplasmic tail, which promotes the interaction between Smo and Costal2 (Cos2). Moreover, we show that Hh regulates both PKA and CK1 phosphorylation of Smo. Thus, the differential phosphorylation of Smo mediates the thresholds of Hh activity.
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24
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Muresan V, Muresan Z. Unconventional functions of microtubule motors. Arch Biochem Biophys 2012; 520:17-29. [PMID: 22306515 PMCID: PMC3307959 DOI: 10.1016/j.abb.2011.12.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 12/21/2011] [Accepted: 12/23/2011] [Indexed: 11/21/2022]
Abstract
With the functional characterization of proteins advancing at fast pace, the notion that one protein performs different functions - often with no relation to each other - emerges as a novel principle of how cells work. Molecular motors are no exception to this new development. Here, we provide an account on recent findings revealing that microtubule motors are multifunctional proteins that regulate many cellular processes, in addition to their main function in transport. Some of these functions rely on their motor activity, but others are independent of it. Of the first category, we focus on the role of microtubule motors in organelle biogenesis, and in the remodeling of the cytoskeleton, especially through the regulation of microtubule dynamics. Of the second category, we discuss the function of microtubule motors as static anchors of the cargo at the destination, and their participation in regulating signaling cascades by modulating interactions between signaling proteins, including transcription factors. We also review atypical forms of transport, such as the cytoplasmic streaming in the oocyte, and the movement of cargo by microtubule fluctuations. Our goal is to provide an overview of these unexpected functions of microtubule motors, and to incite future research in this expanding field.
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Affiliation(s)
- Virgil Muresan
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103, U.S.A
| | - Zoia Muresan
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103, U.S.A
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25
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Xia R, Jia H, Fan J, Liu Y, Jia J. USP8 promotes smoothened signaling by preventing its ubiquitination and changing its subcellular localization. PLoS Biol 2012; 10:e1001238. [PMID: 22253573 PMCID: PMC3254663 DOI: 10.1371/journal.pbio.1001238] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Accepted: 11/23/2011] [Indexed: 01/15/2023] Open
Abstract
Hedgehog regulates the activity of its signal transducer Smoothened by enhancing its interaction with the deubiquitinase USP8, thereby promoting Smoothened translocation to the cell surface and so enhancing Hh signaling. The seven transmembrane protein Smoothened (Smo) is a critical component of the Hedgehog (Hh) signaling pathway and is regulated by phosphorylation, dimerization, and cell-surface accumulation upon Hh stimulation. However, it is not clear how Hh regulates Smo accumulation on the cell surface or how Hh regulates the intracellular trafficking of Smo. In addition, little is known about whether ubiquitination is involved in Smo regulation. In this study, we demonstrate that Smo is multi-monoubiquitinated and that Smo ubiquitination is inhibited by Hh and by phosphorylation. Using an in vivo RNAi screen, we identified ubiquitin-specific protease 8 (USP8) as a deubiquitinase that down-regulates Smo ubiquitination. Inactivation of USP8 increases Smo ubiquitination and attenuates Hh-induced Smo accumulation, leading to decreased Hh signaling activity. Moreover, overexpression of USP8 prevents Smo ubiquitination and elevates Smo accumulation, leading to increased Hh signaling activity. Mechanistically, we show that Hh promotes the interaction of USP8 with Smo aa625–753, which covers the three PKA and CK1 phosphorylation clusters. Finally, USP8 promotes the accumulation of Smo at the cell surface and prevents localization to the early endosomes, presumably by deubiquitinating Smo. Our studies identify USP8 as a positive regulator in Hh signaling by down-regulating Smo ubiquitination and thereby mediating Smo intracellular trafficking. The Hedgehog (Hh) signaling pathway is well known for its role in directing processes such as cell growth, proliferation, and differentiation during embryogenesis. The signal initiated by Hh binding to its receptor, Patched, is transduced by another protein called Smoothened (Smo), which moves from membranes inside the cell to accumulate on the cell surface when Hh binds. This accumulation of Smo on the cell surface is thought to play a central role in maintaining Hh signaling. In this study, we investigated how Hh controls the stability and movement of Smo inside the cell. We found that Smo is modified by addition of a small protein called ubiquitin (Ub), and that Hh regulates the ubiquitination of Smo. We identified an enzyme called USP8 that can remove the ubiquitin modification from Smo, thereby enhancing its signaling activity. Furthermore we show that Hh can enhance the interaction between Smo and USP8. Finally, we discovered that USP8 promotes the movement of Smo from inside the cell to the cell surface. We conclude that Hh promotes the deubiquitination of Smo by USP8, resulting in the relocation of Smo to the cell surface where it enhances Hh signaling.
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Affiliation(s)
- Ruohan Xia
- Department of Molecular and Cellular Biochemistry, Markey Cancer Center, University of Kentucky, Lexington, Kentucky, United States of America
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26
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Abstract
The study of posttranslational regulation of proteins has occupied biochemists for well over a half century. Understanding balanced phosphorylation and dephosphorylation of the proteins may be the key to meeting some of the most pressing scientific challenges. A detailed examination of the phosphorylation of many components in the Hedgehog (Hh) pathway leads to a better understanding of the Hh signaling mechanisms. This chapter describes the precise phosphorylation that evolves during the phosphorylation/dephosphorylation of players in the Hh signaling cascade, including the signal transducer Smoothened and the transcription factor Ci/Gli.
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Affiliation(s)
- Jianhang Jia
- Department of Molecular and Cellular Biochemistry, Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA
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27
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Zhang Y, Mao F, Lu Y, Wu W, Zhang L, Zhao Y. Transduction of the Hedgehog signal through the dimerization of Fused and the nuclear translocation of Cubitus interruptus. Cell Res 2011. [DOI: https://doi.org/10.1038/cr.2011.136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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28
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Zhang Y, Mao F, Lu Y, Wu W, Zhang L, Zhao Y. Transduction of the Hedgehog signal through the dimerization of Fused and the nuclear translocation of Cubitus interruptus. Cell Res 2011; 21:1436-51. [PMID: 21844892 PMCID: PMC3193457 DOI: 10.1038/cr.2011.136] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The Hedgehog (Hh) family of secreted proteins is essential for development in both vertebrates and invertebrates. As one of main morphogens during metazoan development, the graded Hh signal is transduced across the plasma membrane by Smoothened (Smo) through the differential phosphorylation of its cytoplasmic tail, leading to pathway activation and the differential expression of target genes. However, how Smo transduces the graded Hh signal via the Costal2 (Cos2)/Fused (Fu) complex remains poorly understood. Here we present a model of the cell response to a Hh gradient by translating Smo phosphorylation information to Fu dimerization and Cubitus interruptus (Ci) nuclear localization information. Our findings suggest that the phosphorylated C-terminus of Smo recruits the Cos2/Fu complex to the membrane through the interaction between Smo and Cos2, which further induces Fu dimerization. Dimerized Fu is phosphorylated and transduces the Hh signal by phosphorylating Cos2 and Suppressor of Fu (Su(fu)). We further show that this process promotes the dissociation of the full-length Ci (Ci155) and Cos2 or Su(fu), and results in the translocation of Ci155 into the nucleus, activating the expression of target genes.
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Affiliation(s)
- Yanyan Zhang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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29
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Su Y, Ospina JK, Zhang J, Michelson AP, Schoen AM, Zhu AJ. Sequential phosphorylation of smoothened transduces graded hedgehog signaling. Sci Signal 2011; 4:ra43. [PMID: 21730325 PMCID: PMC3526344 DOI: 10.1126/scisignal.2001747] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The correct interpretation of a gradient of the morphogen Hedgehog (Hh) during development requires phosphorylation of the Hh signaling activator Smoothened (Smo); however, the molecular mechanism by which Smo transduces graded Hh signaling is not well understood. We show that regulation of the phosphorylation status of Smo by distinct phosphatases at specific phosphorylated residues creates differential thresholds of Hh signaling. Phosphorylation of Smo was initiated by adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase (PKA) and further enhanced by casein kinase I (CKI). We found that protein phosphatase 1 (PP1) directly dephosphorylated PKA-phosphorylated Smo to reduce signaling mediated by intermediate concentrations of Hh, whereas PP2A specifically dephosphorylated PKA-primed, CKI-phosphorylated Smo to restrict signaling by high concentrations of Hh. We also established a functional link between sequentially phosphorylated Smo species and graded Hh activity. Thus, we propose a sequential phosphorylation model in which precise interpretation of morphogen concentration can be achieved upon versatile phosphatase-mediated regulation of the phosphorylation status of an essential activator in developmental signaling.
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Affiliation(s)
| | | | | | - Andrew P. Michelson
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Adam M. Schoen
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Alan Jian Zhu
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
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30
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Wu JT, Lin WH, Chen WY, Huang YC, Tang CY, Ho MS, Pi H, Chien CT. CSN-mediated deneddylation differentially modulates Ci(155) proteolysis to promote Hedgehog signalling responses. Nat Commun 2011; 2:182. [PMID: 21304511 PMCID: PMC3105314 DOI: 10.1038/ncomms1185] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Accepted: 01/11/2011] [Indexed: 01/15/2023] Open
Abstract
The Hedgehog (Hh) morphogen directs distinct cell responses according to its distinct signalling levels. Hh signalling stabilizes transcription factor cubitus interruptus (Ci) by prohibiting SCFSlimb-dependent ubiquitylation and proteolysis of Ci. How graded Hh signalling confers differential SCFSlimb-mediated Ci proteolysis in responding cells remains unclear. Here, we show that in COP9 signalosome (CSN) mutants, in which deneddylation of SCFSlimb is inactivated, Ci is destabilized in low-to-intermediate Hh signalling cells. As a consequence, expression of the low-threshold Hh target gene dpp is disrupted, highlighting the critical role of CSN deneddylation on low-to-intermediate Hh signalling response. The status of Ci phosphorylation and the level of E1 ubiquitin-activating enzyme are tightly coupled to this CSN regulation. We propose that the affinity of substrate–E3 interaction, ligase activity and E1 activity are three major determinants for substrate ubiquitylation and thereby substrate degradation in vivo. Hedgehog signalling gradients are required for proper wing formation in Drosophila, and Hedgehog is known to regulate the cubitus interruptus transcription factor. Here, the authors show that the COP9 signalosome has a critical role in translating a Hedgehog gradient into a cubitus interruptus gradient.
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Affiliation(s)
- June-Tai Wu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan
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31
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Gallet A. Hedgehog morphogen: from secretion to reception. Trends Cell Biol 2011; 21:238-46. [PMID: 21257310 DOI: 10.1016/j.tcb.2010.12.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 12/08/2010] [Accepted: 12/21/2010] [Indexed: 10/18/2022]
Abstract
A major challenge of developmental biology is to understand how cells coordinate developmental behaviors with their neighbors. To achieve this, cells often employ signaling molecules that emanate from a local source and act at a distance on target cells. The Hedgehog morphogen is an essential signaling molecule required for numerous processes during animal development. Emphasizing the importance of this molecule for both growth control and patterning, Hedgehog signaling activity is often deregulated during cancer formation and progression. The secretion and spread of Hedgehog are not passive processes, but require accessory molecules involved in Hedgehog processing, release, spread and reception. In this review, I focus on the factors that are required to control the spread and activity of Hedgehog, highlighting recent data that have shed light on these processes.
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Affiliation(s)
- Armel Gallet
- Institut de Biologie du Développement & Cancer - IBDC, Université de Nice Sophia-Antipolis, UMR6543 CNRS, Centre de Biochimie, Parc Valrose, 06108 Nice cedex 2, France.
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32
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Nehmé R, Mus-Veteau I. Proteins of the Hedgehog signaling pathway as therapeutic targets against cancer. Expert Rev Proteomics 2010; 7:601-12. [PMID: 20653513 DOI: 10.1586/epr.10.39] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The Hedgehog pathway plays a crucial role in growth and patterning during embryonic development and is involved in stem cell maintenance and proliferation in adult tissues. Mutations that increase the overall activity of the pathway are often associated with a higher incidence of cancers. This article focuses on the mutations, misfoldings and deregulations of the Hedgehog pathway proteins that have been reported to be involved in different tumors, and on small molecules targeting these proteins shown to slow down the growth of certain tumors in various animal models. We propose that proteomics could be a powerful tool to identify new targets of the Hedgehog pathway, enabling the discovery of effective and novel treatments for cancers.
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Affiliation(s)
- Rony Nehmé
- MRC - Laboratory of Molecular Biology, Cambridge, UK
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33
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Jia H, Liu Y, Xia R, Tong C, Yue T, Jiang J, Jia J. Casein kinase 2 promotes Hedgehog signaling by regulating both smoothened and Cubitus interruptus. J Biol Chem 2010; 285:37218-26. [PMID: 20876583 DOI: 10.1074/jbc.m110.174565] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Casein kinase 2 (CK2) is a typical serine/threonine kinase consisting of α and β subunits and has been implicated in many cellular and developmental processes. In this study, we demonstrate that CK2 is a positive regulator of the Hedgehog (Hh) signal transduction pathway. We found that inactivation of CK2 by CK2β RNAi enhances the loss-of-Hh wing phenotype induced by a dominant negative form of Smoothened (Smo). CK2β RNAi attenuates Hh-induced Smo accumulation and down-regulates Hh target gene expression, whereas increasing CK2 activity by coexpressing CK2α and CK2β increases Smo accumulation and induces ectopic Hh target gene expression. We identified the serine residues in Smo that can be phosphorylated by CK2 in vitro. Mutating these serine residues attenuates the ability of Smo to transduce high level Hh signaling activity in vivo. Furthermore, we found that CK2 plays an additional positive role downstream of Smo by regulating the stability of full-length Cubitus interruptus (Ci). CK2β RNAi promotes Ci degradation whereas coexpressing CK2α and CK2β increases the half-life of Ci. We showed that CK2 prevents Ci ubiquitination and degradation by the proteasome. Thus, CK2 promotes Hh signaling activity by regulating multiple pathway components.
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Affiliation(s)
- Hongge Jia
- Department of Molecular and Cellular Biochemistry, Markey Cancer Center, University of Kentucky, Lexington, Kentucky 40536, USA
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34
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Wilson CW, Chuang PT. Mechanism and evolution of cytosolic Hedgehog signal transduction. Development 2010; 137:2079-94. [PMID: 20530542 DOI: 10.1242/dev.045021] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Hedgehog (Hh) signaling is required for embryonic patterning and postnatal physiology in invertebrates and vertebrates. With the revelation that the primary cilium is crucial for mammalian Hh signaling, the prevailing view that Hh signal transduction mechanisms are conserved across species has been challenged. However, more recent progress on elucidating the function of core Hh pathway cytosolic regulators in Drosophila, zebrafish and mice has confirmed that the essential logic of Hh transduction is similar between species. Here, we review Hh signaling events at the membrane and in the cytosol, and focus on parallel and divergent functions of cytosolic Hh regulators in Drosophila and mammals.
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Affiliation(s)
- Christopher W Wilson
- Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA
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35
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Raisin S, Ruel L, Ranieri N, Staccini-Lavenant L, Thérond PP. Dynamic phosphorylation of the kinesin Costal-2 in vivo reveals requirement of fused kinase activity for all levels of hedgehog signalling. Dev Biol 2010; 344:119-28. [PMID: 20435030 DOI: 10.1016/j.ydbio.2010.04.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Revised: 04/21/2010] [Accepted: 04/22/2010] [Indexed: 11/26/2022]
Abstract
Hedgehog (Hh) proteins are secreted molecules that play an essential role in development and tumorigenesis. In Drosophila cultured cells, phosphorylation of the kinesin-like Costal2 (Cos2) protein at Ser572 is triggered by the kinase fused (Fu) upon Hh pathway activation. Here, we validate the first phospho-antibody for one of the Hh pathway components, Cos2, as a universal in situ readout of Hh signal transduction. For the first time, this tool allows the visualisation of a gradient of signalling activity and therefore the range of the activating Hh ligand in different tissues. We also show that, in vivo, Fu kinase is activated by and necessary to transduce all levels of intracellular Hh signalling. Our study fills a gap in the understanding of the Hh pathway by showing that the molecular cascade leading to Cos2 phosphorylation is conserved in all cells activated by Hh. Therefore, we propose that the extracellular Hh information is conveyed to an intracellular signal through graded Fu kinase activity.
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Affiliation(s)
- S Raisin
- Université de Nice/Sophia-Antipolis, Institute of Developmental Biology and Cancer, UMR6543-CNRS, UFR Sciences, Parc Valrose, 06108 Nice cedex 02, France
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36
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Goetz SC, Anderson KV. The primary cilium: a signalling centre during vertebrate development. Nat Rev Genet 2010; 11:331-44. [PMID: 20395968 DOI: 10.1038/nrg2774] [Citation(s) in RCA: 1386] [Impact Index Per Article: 99.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The primary cilium has recently stepped into the spotlight, as a flood of data show that this organelle has crucial roles in vertebrate development and human genetic diseases. Cilia are required for the response to developmental signals, and evidence is accumulating that the primary cilium is specialized for hedgehog signal transduction. The formation of cilia, in turn, is regulated by other signalling pathways, possibly including the planar cell polarity pathway. The cilium therefore represents a nexus for signalling pathways during development. The connections between cilia and developmental signalling have begun to clarify the basis of human diseases associated with ciliary dysfunction.
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Affiliation(s)
- Sarah C Goetz
- Developmental Biology Program, Sloan-Kettering Institute, New York, New York 10065, USA
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37
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Abstract
The discovery of a Sonic Hedgehog (Shh) signaling pathway in the mature vertebrate CNS has paved the way to the characterization of the functional roles of Shh signals in normal and diseased brain. Shh is proposed to participate in the establishment and maintenance of adult neurogenic niches and to regulate the proliferation of neuronal or glial precursors in several brain areas. Consistent with its role during brain development, misregulation of Shh signaling is associated with tumorigenesis while its recruitement in damaged neural tissue might be part of the regenerating process. This review focuses on the most recent data of the Hedgehog pathway in the adult brain and its relevance as a novel therapeutic approach for brain diseases including brain tumors.
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Affiliation(s)
- Elisabeth Traiffort
- CNRS, Alfred Fessard Institute of Neurobiology, Laboratory of Neurobiology and Development, UPR-3294, Signal Transduction and Developmental Neuropharmacology Team, Gif-sur-Yvette, France.
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38
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Ayers KL, Thérond PP. Evaluating Smoothened as a G-protein-coupled receptor for Hedgehog signalling. Trends Cell Biol 2010; 20:287-98. [PMID: 20207148 DOI: 10.1016/j.tcb.2010.02.002] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 02/05/2010] [Accepted: 02/09/2010] [Indexed: 11/16/2022]
Abstract
The Hedgehog signalling pathway controls numerous developmental processes. In response to Hedgehog, Smoothened (Smo), a seven-pass transmembrane protein, orchestrates pathway signalling and controls transcription factor activation. In the absence of Hedgehog, the receptor Patched indirectly inhibits Smo in a catalytic manner. Many questions surrounding Smo activation and signalling remain. Recent findings in Drosophila and vertebrate systems have provided strong evidence that Smo acts as a G-protein-coupled receptor. We discuss the role and regulation of Smo and reassess similarities between Smo and G-protein-coupled receptors. We also examine recently identified members of the invertebrate and vertebrate Smo signalling cascades that are typical components of G-protein-coupled receptor pathways. Greater understanding of the mechanisms of Smo activation and its signalling pathways will allow implementation of novel strategies to target disorders related to disruption of Hh signalling.
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Affiliation(s)
- Katie L Ayers
- Institute of Developmental Biology and Cancer, CNRS UMR6543, Université Nice - Sophia Antipolis, Parc Valrose, 06108 Nice Cedex 2, France
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39
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Stecca B, Ruiz i Altaba A. Context-dependent regulation of the GLI code in cancer by HEDGEHOG and non-HEDGEHOG signals. J Mol Cell Biol 2010; 2:84-95. [PMID: 20083481 DOI: 10.1093/jmcb/mjp052] [Citation(s) in RCA: 201] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A surprisingly large and unrelated number of human tumors depend on sustained HEDGEHOG-GLI (HH-GLI) signaling for growth. This includes cancers of the skin, brain, colon, lungs, prostate, blood and pancreas among others. The basis of such commonality is not obvious. HH-GLI signaling has also been shown to be active in and required for cancer stem cell survival and expansion in different cancer types, and its activity is essential not only for tumor growth but also for recurrence and metastatic growth, two key medical problems. Here we review recent data on the role of HH-GLI signaling in cancer focusing on the role of the GLI code, the regulated combinatorial and cooperative function of repressive and activating forms of all Gli transcription factors, as a signaling nexus that integrates not only HH signals but also those of multiple tumor suppressors and oncogenes. Recent data support the view that the context-dependent regulation of the GLI code by oncogenes and tumor suppressors constitutes a basis for the widespread involvement of GLI1 in human cancers, representing a perversion of its normal role in the control of stem cell lineages during normal development and homeostasis.
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Affiliation(s)
- Barbara Stecca
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva CH-1211, Switzerland
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40
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Mechanisms of protein kinase A anchoring. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2010; 283:235-330. [PMID: 20801421 DOI: 10.1016/s1937-6448(10)83005-9] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The second messenger cyclic adenosine monophosphate (cAMP), which is produced by adenylyl cyclases following stimulation of G-protein-coupled receptors, exerts its effect mainly through the cAMP-dependent serine/threonine protein kinase A (PKA). Due to the ubiquitous nature of the cAMP/PKA system, PKA signaling pathways underlie strict spatial and temporal control to achieve specificity. A-kinase anchoring proteins (AKAPs) bind to the regulatory subunit dimer of the tetrameric PKA holoenzyme and thereby target PKA to defined cellular compartments in the vicinity of its substrates. AKAPs promote the termination of cAMP signals by recruiting phosphodiesterases and protein phosphatases, and the integration of signaling pathways by binding additional signaling proteins. AKAPs are a heterogeneous family of proteins that only display similarity within their PKA-binding domains, amphipathic helixes docking into a hydrophobic groove formed by the PKA regulatory subunit dimer. This review summarizes the current state of information on compartmentalized cAMP/PKA signaling with a major focus on structural aspects, evolution, diversity, and (patho)physiological functions of AKAPs and intends to outline newly emerging directions of the field, such as the elucidation of AKAP mutations and alterations of AKAP expression in human diseases, and the validation of AKAP-dependent protein-protein interactions as new drug targets. In addition, alternative PKA anchoring mechanisms employed by noncanonical AKAPs and PKA catalytic subunit-interacting proteins are illustrated.
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41
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Goetz SC, Ocbina PJR, Anderson KV. The primary cilium as a Hedgehog signal transduction machine. Methods Cell Biol 2009; 94:199-222. [PMID: 20362092 DOI: 10.1016/s0091-679x(08)94010-3] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The Hedgehog (Hh) signal transduction pathway is essential for the development and patterning of numerous organ systems, and has important roles in a variety of human cancers. Genetic screens for mouse embryonic patterning mutants first showed a connection between mammalian Hh signaling and intraflagellar transport (IFT), a process required for construction of the primary cilium, a small cellular projection found on most vertebrate cells. Additional genetic and cell biological studies have provided very strong evidence that mammalian Hh signaling depends on the primary cilium. Here, we review the evidence that defines the integral roles that IFT proteins and cilia play in the regulation of the Hh signal transduction pathway in vertebrates. We discuss the mechanisms that control localization of Hh pathway proteins to the cilium, focusing on the transmembrane protein Smoothened (Smo), which moves into the cilium in response to Hh ligand. The phenotypes caused by loss of cilia-associated proteins are complex, which suggests that cilia and IFT play active roles in mediating Hh signaling rather than serving simply as a compartment in which pathway components are concentrated. Hh signaling in Drosophila does not depend on cilia, but there appear to be ancient links between cilia and components of the Hh pathway that may reveal how this fundamental difference between the Drosophila and mammalian Hh pathways arose in evolution.
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Affiliation(s)
- Sarah C Goetz
- Developmental Biology Program, Sloan-Kettering Institute, 1275 York Avenue, New York, New York 10065, USA
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42
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Farzan SF, Stegman MA, Ogden SK, Ascano M, Black KE, Tacchelly O, Robbins DJ. A quantification of pathway components supports a novel model of Hedgehog signal transduction. J Biol Chem 2009; 284:28874-84. [PMID: 19717563 PMCID: PMC2781433 DOI: 10.1074/jbc.m109.041608] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2009] [Revised: 08/25/2009] [Indexed: 11/06/2022] Open
Abstract
The secreted protein Hedgehog (Hh) plays a critical instructional role during metazoan development. In Drosophila, Hh signaling is interpreted by a set of conserved, downstream effectors that differentially localize and interact to regulate the stability and activity of the transcription factor Cubitus interruptus. Two essential models that integrate genetic, cell biological, and biochemical information have been proposed to explain how these signaling components relate to one another within the cellular context. As the molar ratios of the signaling effectors required in each of these models are quite different, quantitating the cellular ratio of pathway components could distinguish these two models. Here, we address this important question using a set of purified protein standards to perform a quantitative analysis of Drosophila cell lysates for each downstream pathway component. We determine each component's steady-state concentration within a given cell, demonstrate the molar ratio of Hh signaling effectors differs more than two orders of magnitude and that this ratio is conserved in vivo. We find that the G-protein-coupled transmembrane protein Smoothened, an activating component, is present in limiting amounts, while a negative pathway regulator, Suppressor of Fused, is present in vast molar excess. Interestingly, despite large differences in the steady-state ratio, all downstream signaling components exist in an equimolar membrane-associated complex. We use these quantitative results to re-evaluate the current models of Hh signaling and now propose a novel model of signaling that accounts for the stoichiometric differences observed between various Hh pathway components.
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Affiliation(s)
- Shohreh F. Farzan
- From the Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755 and
| | - Melanie A. Stegman
- From the Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755 and
| | - Stacey K. Ogden
- From the Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755 and
| | - Manuel Ascano
- From the Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755 and
| | - Kendall E. Black
- From the Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755 and
| | - Ofelia Tacchelly
- From the Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755 and
| | - David J. Robbins
- From the Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755 and
- the Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03756
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43
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Chen MH, Wilson CW, Li YJ, Law KKL, Lu CS, Gacayan R, Zhang X, Hui CC, Chuang PT. Cilium-independent regulation of Gli protein function by Sufu in Hedgehog signaling is evolutionarily conserved. Genes Dev 2009; 23:1910-28. [PMID: 19684112 DOI: 10.1101/gad.1794109] [Citation(s) in RCA: 280] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
A central question in Hedgehog (Hh) signaling is how evolutionarily conserved components of the pathway might use the primary cilium in mammals but not fly. We focus on Suppressor of fused (Sufu), a major Hh regulator in mammals, and reveal that Sufu controls protein levels of full-length Gli transcription factors, thus affecting the production of Gli activators and repressors essential for graded Hh responses. Surprisingly, despite ciliary localization of most Hh pathway components, regulation of Gli protein levels by Sufu is cilium-independent. We propose that Sufu-dependent processes in Hh signaling are evolutionarily conserved. Consistent with this, Sufu regulates Gli protein levels by antagonizing the activity of Spop, a conserved Gli-degrading factor. Furthermore, addition of zebrafish or fly Sufu restores Gli protein function in Sufu-deficient mammalian cells. In contrast, fly Smo is unable to translocate to the primary cilium and activate the mammalian Hh pathway. We also uncover a novel positive role of Sufu in regulating Hh signaling, resulting from its control of both Gli activator and repressor function. Taken together, these studies delineate important aspects of cilium-dependent and cilium-independent Hh signal transduction and provide significant mechanistic insight into Hh signaling in diverse species.
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Affiliation(s)
- Miao-Hsueh Chen
- Cardiovascular Research Institute, University of California at San Francisco, San Francisco, California 94158, USA
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Büttner A, Seifert K, Cottin T, Sarli V, Tzagkaroulaki L, Scholz S, Giannis A. Synthesis and biological evaluation of SANT-2 and analogues as inhibitors of the hedgehog signaling pathway. Bioorg Med Chem 2009; 17:4943-54. [PMID: 19541490 DOI: 10.1016/j.bmc.2009.06.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Revised: 05/29/2009] [Accepted: 06/02/2009] [Indexed: 12/21/2022]
Abstract
Hedgehog (Hh) signaling plays an important role in cell signaling of embryonic development and adult tissue homeostasis. In vertebrates, the hh gene encodes three different unique proteins: sonic hedgehog (Shh), desert hedgehog (Dhh) and indian hedgehog (Ihh). Disruption of the Hh signaling pathway leads to severe disorders in the development of vertebrates whereas aberrant activation of the Hh pathway has been associated with several malignancies including Gorlin syndrome (a disorder predisposing to basal cell carcinoma, medulloblastoma and rhabdomyosarcoma), prostate, pancreatic and breast cancers. In vivo evidence suggests the antagonism of excessive Hh signaling provides a route to unique mechanism-based anti-cancer therapies. Recently the small molecule SANT-2 was identified as a potent antagonist of Hh-signaling pathway. Here, we describe the synthesis, SAR studies as well as biological evaluation of SANT-2 and its analogues. Fifteen SANT-2 derivatives were synthesized and analyzed for their interference with the expression of the Hh target gene Gli1 in a reporter gene assay. By comparison of structure and activity important molecular descriptors for Gli inhibition could be identified. Furthermore we identified derivative TC-132 that was slightly more potent than the parent compound SANT-2. Selected compounds were tested for Hh related teratogenic effects in the small teleost model medaka. Albeit Gli expression has indicated a 16-fold higher Hh-inhibiting activity than observed for the plant alkaloid cyclopamine, none of the tested compounds were able to induce the cyclopamine-specific phenotype in the medaka assay.
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Affiliation(s)
- Anita Büttner
- University of Leipzig, Institute for Organic Chemistry, Johannisallee 29, D-04103 Leipzig, Germany
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Modulation of osteocalcin expression by purmorphamine derivatives. Genes Genomics 2009. [DOI: 10.1007/bf03191198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Abstract
The Hedgehog (Hh) family of proteins control cell growth, survival, and fate, and pattern almost every aspect of the vertebrate body plan. The use of a single morphogen for such a wide variety of functions is possible because cellular responses to Hh depend on the type of responding cell, the dose of Hh received, and the time cells are exposed to Hh. The Hh gradient is shaped by several proteins that are specifically required for Hh processing, secretion, and transport through tissues. The mechanism of cellular response, in turn, incorporates multiple feedback loops that fine-tune the level of signal sensed by the responding cells. Germline mutations that subtly affect Hh pathway activity are associated with developmental disorders, whereas somatic mutations activating the pathway have been linked to multiple forms of human cancer. This review focuses broadly on our current understanding of Hh signaling, from mechanisms of action to cellular and developmental functions. In addition, we review the role of Hh in the pathogenesis of human disease and the possibilities for therapeutic intervention.
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Affiliation(s)
- Markku Varjosalo
- Department of Molecular Medicine, National Public Health Institute (KTL), and Genome-Scale Biology Program, Biomedicum Helsinki, Institute of Biomedicine and High Throughput Center, Faculty of Medicine, University of Helsinki, Helsinki FI-00014, Finland
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