1
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Voss JH, Koszegi Z, Yan Y, Shorter E, Grätz L, Lanner JT, Calebiro D, Schulte G. WNT-induced association of Frizzled and LRP6 is not sufficient for the initiation of WNT/β-catenin signaling. Nat Commun 2025; 16:4848. [PMID: 40413190 PMCID: PMC12103576 DOI: 10.1038/s41467-025-60096-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2024] [Accepted: 05/15/2025] [Indexed: 05/27/2025] Open
Abstract
The Wingless/Int-1 (WNT) signaling network is essential to orchestrate central physiological processes such as embryonic development and tissue homeostasis. In the currently held tenet, WNT/β-catenin signaling is initiated by WNT-induced recruitment of Frizzleds (FZDs) and LRP5/6 followed by the formation of a multiprotein signalosome complex. Here, we use bioluminescence resonance energy transfer (BRET) to show that different WNT paralogs dynamically trigger FZD-LRP6 association. While WNT-induced receptor interaction was independent of C-terminal LRP6 phosphorylation, it was allosterically modulated by binding of the phosphoprotein Dishevelled (DVL) to FZD. WNT-16B emerged as a ligand of particular interest, as it efficiently promoted FZD-LRP6 association but, unlike WNT-3A, did not lead to WNT/β-catenin signaling. Transcriptomic analysis further revealed distinct transcriptional fingerprints of WNT-3A and WNT-16B stimulation in HEK293 cells. Additionally, single-molecule tracking demonstrated that, despite increasing FZD5 and LRP6 confinement, WNT-16B stimulation did not result in formation of higher-order receptor clusters, in contrast to WNT-3A. Our results suggest that FZD-WNT-LRP5/6 complex formation alone is not sufficient for the initiation of WNT/β-catenin signaling. Instead, we propose a two-step model, where initial ligand-induced FZD-LRP6 association must be followed by receptor clustering into higher-order complexes and subsequent phosphorylation of LRP6 for efficient activation of WNT/β-catenin signaling.
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Affiliation(s)
- Jan Hendrik Voss
- Karolinska Institutet, Department of Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, S-17165, Stockholm, Sweden
| | - Zsombor Koszegi
- Department of Metabolism and Systems Science, College of Medicine and Health, University of Birmingham, Birmingham, B15 2TT, UK
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, B15 2TT, UK
| | - Yining Yan
- Karolinska Institutet, Department of Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, S-17165, Stockholm, Sweden
| | - Emily Shorter
- Karolinska Institutet, Department of Physiology & Pharmacology, Sec. Molecular Muscle Physiology & Pathophysiology, Biomedicum, S-17165, Stockholm, Sweden
| | - Lukas Grätz
- Karolinska Institutet, Department of Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, S-17165, Stockholm, Sweden
| | - Johanna T Lanner
- Karolinska Institutet, Department of Physiology & Pharmacology, Sec. Molecular Muscle Physiology & Pathophysiology, Biomedicum, S-17165, Stockholm, Sweden
| | - Davide Calebiro
- Department of Metabolism and Systems Science, College of Medicine and Health, University of Birmingham, Birmingham, B15 2TT, UK
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, B15 2TT, UK
| | - Gunnar Schulte
- Karolinska Institutet, Department of Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, S-17165, Stockholm, Sweden.
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2
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Lee JW, Lee DY, Baek S, Jeong JY, Huh WK. Sensitive detection of pertussis toxin in acellular pertussis vaccines using HRH1-mediated calcium signaling. Vaccine 2025; 54:127056. [PMID: 40158234 DOI: 10.1016/j.vaccine.2025.127056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2024] [Revised: 03/12/2025] [Accepted: 03/18/2025] [Indexed: 04/02/2025]
Abstract
Accurate detection and quantification of residual pertussis toxin (PTx), a key virulence factor of Bordetella pertussis, are essential for the production and safety testing of acellular pertussis vaccines. Traditional methods, such as the histamine sensitization test and the CHO cell clustering assay, face challenges including low reproducibility, difficulty in standardization, and interference from vaccine adjuvants. To address these limitations, we developed a biosensor for PTx detection based on histamine receptor H1 (HRH1)-induced calcium signaling in MDA-MB-231 cells, representing an unexplored approach for PTx detection. Using mini G protein recruitment and Gα activation assays, we found that HRH1 activates both Gαq and Gαi heterotrimers. The presence of PTx disrupts histamine-induced Gαi binding to HRH1, resulting in a compensatory increase in Gαq binding and enhanced calcium signaling. By normalizing sustained calcium levels to the percentage of the maximal calcium response, we achieved higher accuracy and reliability in detecting PTx, even in the presence of adjuvants. Our method provides quantitative detection of PTx activity with high sensitivity, achieving a limit of detection in the pg/ml range in acellular pertussis vaccines spiked with PTx. This work introduces a robust and convenient calcium assay using MDA-MB-231 cells, which predominantly express HRH1 with negligible expression of other HRH receptors, as an effective method for PTx detection in vaccine safety testing.
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Affiliation(s)
- Jin-Woo Lee
- School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Dong-Yeop Lee
- School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Seungwon Baek
- School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Jae-Yeon Jeong
- GPCR Therapeutics Inc., Gwanak-gu, Seoul 08790, Republic of Korea.
| | - Won-Ki Huh
- School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea; GPCR Therapeutics Inc., Gwanak-gu, Seoul 08790, Republic of Korea; Institute of Microbiology, Seoul National University, Seoul 08826, Republic of Korea.
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3
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Choi H, Cho SH, Park JH, Seok YJ. Fructose-responsive regulation by FruR in Faecalibacterium prausnitzii for its intestinal colonization. Commun Biol 2025; 8:426. [PMID: 40082586 PMCID: PMC11906611 DOI: 10.1038/s42003-025-07878-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2024] [Accepted: 03/03/2025] [Indexed: 03/16/2025] Open
Abstract
Faecalibacterium prausnitzii, a dominant member of healthy human gut microbiota, exhibits a strong positive correlation with fecal fructose levels, suggesting fructose as a key energy source for its colonization and persistence. This study explores the regulatory mechanisms governing the fru operon in F. prausnitzii, responsible for fructose uptake and metabolism. Here, we demonstrate that FruR, a DeoR family transcriptional regulator, orchestrates fru operon expression through interactions with fructose-1-phosphate (F1P) and HPr2, the histidine-containing phosphocarrier protein. The F1P-HPr2(Ser-P)-FruR complex enhances RNA polymerase binding to the fru promoter, with stronger affinity for specific operator motifs compared to apo-FruR. F1P induces structural modifications in FruR that strengthen its interaction with HPr2 and alter its DNA recognition pattern, facilitating RNA polymerase access to the promoter. In vivo experiments in mice demonstrate increased F. prausnitzii abundance alongside upregulated fru operon expression in fructose-rich environments. This study provides new insights into how fructose availability modulates fru operon regulation and promotes F. prausnitzii colonization in the host intestine.
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Affiliation(s)
- HyeLim Choi
- School of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Sang-Hyun Cho
- School of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Joo-Hong Park
- School of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Yeong-Jae Seok
- School of Biological Sciences, Seoul National University, Seoul, Republic of Korea.
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4
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Kim HT, Jeong JY, Huh WK. Regulation of CXCR4 function by S1P 1 through heteromerization. Cell Commun Signal 2025; 23:111. [PMID: 40012038 PMCID: PMC11863771 DOI: 10.1186/s12964-025-02099-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2024] [Accepted: 02/09/2025] [Indexed: 02/28/2025] Open
Abstract
BACKGROUND The trafficking of immune cells between lymphoid organs and circulation depends on gradients of CXCL12 and sphingosine-1-phosphate (S1P), mediated through their cognate receptors C-X-C chemokine receptor type 4 (CXCR4) and S1P receptor type 1 (S1P1). S1P1 facilitates the egress of hematopoietic stem cells and lymphocytes by counteracting CXCR4-mediated retention signals. However, the molecular mechanisms underlying this interplay remain poorly understood. In this study, we uncover CXCR4-S1P1 heteromerization and explore their functional interactions. METHODS Bimolecular fluorescence complementation (BiFC) assay, proximity ligation assay (PLA), and quantitative bioluminescence resonance energy transfer (BRET) assay were employed to detect CXCR4-S1P1 heteromerization. Functional properties of the heteromers were assessed using cAMP assay, G protein activation, β-arrestin recruitment, ligand binding, calcium mobilization, and transwell migration assays. S1P1-overexpressing Jurkat T cells were generated via lentiviral transduction, while S1P1-deficient KARPAS299 cells and β-arrestin1/2-deficient HEK293A cells were constructed using the CRISPR/Cas9 system. RESULTS CXCR4-S1P1 heteromerization was observed in HEK293A cells overexpressing both receptors. The S1P/S1P1 axis interfered with CXCR4-mediated signaling, while CXCR4 did not affect S1P1-mediated signaling, indicating a unidirectional modulation of CXCR4 by S1P1. CXCL12 binding to CXCR4 remained unchanged in the presence of S1P1, and interference of CXCL12-induced Gαi activation by S1P1 was observed in β-arrestin1/2-deficient cells. BRET analysis revealed that S1P1 interfered with CXCR4-Gαi pre-association and CXCR4 oligomerization, both of which are critical for CXCR4 function. Domain-swapping experiments identified transmembrane domain 3 of S1P1 as essential for this modulation. In Jurkat T cells overexpressing S1P1, CXCR4-mediated signaling and cell migration were diminished, whereas these functions were enhanced in S1P1-deficient KARPAS299 cells. Co-activation of S1P1 attenuated CXCL12-induced migration, while pretreatment with S1P or FTY720-phosphate increased CXCR4-mediated migration by downregulating surface S1P1 in KARPAS299 cells. In primary T cells, PLA confirmed CXCR4-S1P1 heteromerization, and S1P interfered with CXCL12-induced migration. CONCLUSIONS This study identifies CXCR4-S1P1 heteromers and demonstrates a unidirectional modulation of CXCR4 by S1P1. S1P1 affects CXCR4 function by disrupting its G protein pre-association and oligomerization. These findings underscore the regulatory role of the S1P/S1P1 axis in CXCR4 signaling within the heteromeric context and provide novel insights into the intricate mechanisms governing immune cell trafficking.
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Affiliation(s)
- Hyun-Tae Kim
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jae-Yeon Jeong
- GPCR Therapeutics Inc, Gwanak-gu, Seoul, 08790, Republic of Korea.
| | - Won-Ki Huh
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
- GPCR Therapeutics Inc, Gwanak-gu, Seoul, 08790, Republic of Korea.
- Institute of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea.
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5
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Yadava S, Reddy DH, Nakka VP, Anusha VL, Dumala N, Viswanadh MK, Chakravarthi G, Nalluri BN, Ramakrishna K. Unravelling neuroregenerative and neuroprotective roles of Wnt/β-catenin pathway in ischemic stroke: Insights into molecular mechanisms. Neuroscience 2025; 565:527-547. [PMID: 39681254 DOI: 10.1016/j.neuroscience.2024.12.024] [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: 11/01/2024] [Revised: 12/07/2024] [Accepted: 12/12/2024] [Indexed: 12/18/2024]
Abstract
Stroke is a serious condition often resulting in mortality or long-term disability, causing cognitive, memory, and motor impairments. A reduction in cerebral blood flow below critical levels defines the ischemic core and penumbra: the core undergoes irreversible damage, while the penumbra remains viable but functionally impaired. This functional impairment activates complex cell signaling pathways that determine cell survival or death, making the penumbra a key target for therapeutic interventions to prevent further damage. The Wnt/β-catenin (WβC) signaling pathway has emerged as a potential neuroprotective mechanism, promoting neurogenesis, angiogenesis, neuronal connectivity, and maintaining blood-brain barrier integrity after stroke. Activation of the WβC pathway also mitigates oxidative stress, inflammation, and apoptosis in ischemic regions, enhancing its neuroprotective effects. However, the overexpression of GSK3β and DKK1, or the presence of their agonists, can counteract these benefits. This review explores the therapeutic potential of WβC signaling, highlighting the effects of pharmacological modulation through antagonists, agonists, synthetic chemicals, natural products, stem cells, and macromolecules in preclinical models of ischemic stroke. While preclinical evidence supports the benefits of WβC activation, its role in human stroke requires further investigation. Additionally, the review discusses the potential adverse effects of prolonged WβC activation and suggests strategies to mitigate them. Overall, WβC signaling holds promise as a therapeutic target, offering insights into stroke pathophysiology and informing the development of novel treatment strategies.
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Affiliation(s)
- Srikanth Yadava
- KL College of Pharmacy, Koneru Lakshmaiah Education Foundation, Vaddeswaram, India.
| | | | - Venkata Prasuja Nakka
- Department of Systems and Computational Biology, School of Life Sciences, University of Hyderabad, 500046, India.
| | | | - Naresh Dumala
- KL College of Pharmacy, Koneru Lakshmaiah Education Foundation, Vaddeswaram, India.
| | - Matte Kasi Viswanadh
- KL College of Pharmacy, Koneru Lakshmaiah Education Foundation, Vaddeswaram, India.
| | | | - Buchi N Nalluri
- KL College of Pharmacy, Koneru Lakshmaiah Education Foundation, Vaddeswaram, India
| | - Kakarla Ramakrishna
- KL College of Pharmacy, Koneru Lakshmaiah Education Foundation, Vaddeswaram, India.
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6
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Nayak A, Streiff H, Gonzalez I, Adekoya OO, Silva I, Shenoy AK. Wnt Pathway-Targeted Therapy in Gastrointestinal Cancers: Integrating Benchside Insights with Bedside Applications. Cells 2025; 14:178. [PMID: 39936971 PMCID: PMC11816596 DOI: 10.3390/cells14030178] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2024] [Revised: 01/05/2025] [Accepted: 01/07/2025] [Indexed: 02/13/2025] Open
Abstract
The Wnt signaling pathway is critical in the onset and progression of gastrointestinal (GI) cancers. Anomalies in this pathway, often stemming from mutations in critical components such as adenomatous polyposis coli (APC) or β-catenin, lead to uncontrolled cell proliferation and survival. In the case of colorectal cancer, dysregulation of the Wnt pathway drives tumor initiation and growth. Similarly, aberrant Wnt signaling contributes to tumor development, metastasis, and resistance to therapy in other GI cancers, such as gastric, pancreatic, and hepatocellular carcinomas. Targeting the Wnt pathway or its downstream effectors has emerged as a promising therapeutic strategy for combating these highly aggressive GI malignancies. Here, we review the dysregulation of the Wnt signaling pathway in the pathogenesis of GI cancers and further explore the therapeutic potential of targeting the various components of the Wnt pathway. Furthermore, we summarize and integrate the preclinical evidence supporting the therapeutic efficacy of potent Wnt pathway inhibitors with completed and ongoing clinical trials in GI cancers. Additionally, we discuss the challenges of Wnt pathway-targeted therapies in GI cancers to overcome these concerns for effective clinical translation.
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7
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Bruguera ES, Mahoney JP, Weis WI. The co-receptor Tetraspanin12 directly captures Norrin to promote ligand-specific β-catenin signaling. eLife 2025; 13:RP96743. [PMID: 39745873 DOI: 10.7554/elife.96743] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2025] Open
Abstract
Wnt/β-catenin signaling directs animal development and tissue renewal in a tightly controlled, cell- and tissue-specific manner. In the mammalian central nervous system, the atypical ligand Norrin controls angiogenesis and maintenance of the blood-brain barrier and blood-retina barrier through the Wnt/β-catenin pathway. Like Wnt, Norrin activates signaling by binding and heterodimerizing the receptors Frizzled (Fzd) and low-density lipoprotein receptor-related protein 5 or 6 (LRP5/6), leading to membrane recruitment of the intracellular transducer Dishevelled (Dvl) and ultimately stabilizing the transcriptional coactivator β-catenin. Unlike Wnt, the cystine knot ligand Norrin only signals through Fzd4 and additionally requires the co-receptor Tetraspanin12 (Tspan12); however, the mechanism underlying Tspan12-mediated signal enhancement is unclear. It has been proposed that Tspan12 integrates into the Norrin-Fzd4 complex to enhance Norrin-Fzd4 affinity or otherwise allosterically modulate Fzd4 signaling. Here, we measure direct, high-affinity binding between purified Norrin and Tspan12 in a lipid environment and use AlphaFold models to interrogate this interaction interface. We find that Tspan12 and Fzd4 can simultaneously bind Norrin and that a pre-formed Tspan12/Fzd4 heterodimer, as well as cells co-expressing Tspan12 and Fzd4, more efficiently capture low concentrations of Norrin than Fzd4 alone. We also show that Tspan12 competes with both heparan sulfate proteoglycans and LRP6 for Norrin binding and that Tspan12 does not impact Fzd4-Dvl affinity in the presence or absence of Norrin. Our findings suggest that Tspan12 does not allosterically enhance Fzd4 binding to Norrin or Dvl, but instead functions to directly capture Norrin upstream of signaling.
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Affiliation(s)
- Elise S Bruguera
- Departments of Molecular & Cellular Physiology and Structural Biology, Stanford University School of Medicine, Stanford, United States
| | - Jacob P Mahoney
- Departments of Molecular & Cellular Physiology and Structural Biology, Stanford University School of Medicine, Stanford, United States
| | - William I Weis
- Departments of Molecular & Cellular Physiology and Structural Biology, Stanford University School of Medicine, Stanford, United States
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8
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Bruguera ES, Mahoney JP, Weis WI. The co-receptor Tetraspanin12 directly captures Norrin to promote ligand-specific β-catenin signaling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.03.578714. [PMID: 38352533 PMCID: PMC10862866 DOI: 10.1101/2024.02.03.578714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Wnt/β-catenin signaling directs animal development and tissue renewal in a tightly controlled, cell- and tissue-specific manner. In the mammalian central nervous system, the atypical ligand Norrin controls angiogenesis and maintenance of the blood-brain barrier and blood-retina barrier through the Wnt/β-catenin pathway. Like Wnt, Norrin activates signaling by binding and heterodimerizing the receptors Frizzled (Fzd) and Low-density lipoprotein receptor-related protein 5 or 6 (LRP5/6), leading to membrane recruitment of the intracellular transducer Dishevelled (Dvl) and ultimately stabilizing the transcriptional coactivator β-catenin. Unlike Wnt, the cystine-knot ligand Norrin only signals through Fzd4 and additionally requires the co-receptor Tetraspanin12 (Tspan12); however, the mechanism underlying Tspan12-mediated signal enhancement is unclear. It has been proposed that Tspan12 integrates into the Norrin-Fzd4 complex to enhance Norrin-Fzd4 affinity or otherwise allosterically modulate Fzd4 signaling. Here, we measure direct, high-affinity binding between purified Norrin and Tspan12 in a lipid environment and use AlphaFold models to interrogate this interaction interface. We find that Tspan12 and Fzd4 can simultaneously bind Norrin and that a pre-formed Tspan12/Fzd4 heterodimer, as well as cells co-expressing Tspan12 and Fzd4, more efficiently capture low concentrations of Norrin than Fzd4 alone. We also show that Tspan12 competes with both heparan sulfate proteoglycans and LRP6 for Norrin binding and that Tspan12 does not impact Fzd4-Dvl affinity in the presence or absence of Norrin. Our findings suggest that Tspan12 does not allosterically enhance Fzd4 binding to Norrin or Dvl, but instead functions to directly capture Norrin upstream of signaling.
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Affiliation(s)
- Elise S Bruguera
- Departments of Molecular & Cellular Physiology and Structural Biology, Stanford University School of Medicine, Stanford, CA 94305
| | - Jacob P Mahoney
- Departments of Molecular & Cellular Physiology and Structural Biology, Stanford University School of Medicine, Stanford, CA 94305
| | - William I Weis
- Departments of Molecular & Cellular Physiology and Structural Biology, Stanford University School of Medicine, Stanford, CA 94305
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9
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Schulte G. International Union of Basic and Clinical Pharmacology CXV: The Class F of G Protein-Coupled Receptors. Pharmacol Rev 2024; 76:1009-1037. [PMID: 38955509 DOI: 10.1124/pharmrev.124.001062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/10/2024] [Accepted: 05/17/2024] [Indexed: 07/04/2024] Open
Abstract
The class F of G protein-coupled receptors (GPCRs) consists of 10 Frizzleds (FZD1-10) and Smoothened (SMO). FZDs bind and are activated by secreted lipoglycoproteins of the Wingless/Int-1 (WNT) family, and SMO is indirectly activated by the Hedgehog (Hh) family of morphogens acting on the transmembrane protein Patched. The advance of our understanding of FZDs and SMO as dynamic transmembrane receptors and molecular machines, which emerged during the past 14 years since the first-class F GPCR IUPHAR nomenclature report, justifies an update. This article focuses on the advances in molecular pharmacology and structural biology providing new mechanistic insight into ligand recognition, receptor activation mechanisms, signal initiation, and signal specification. Furthermore, class F GPCRs continue to develop as drug targets, and novel technologies and tools such as genetically encoded biosensors and CRISP/Cas9 edited cell systems have contributed to refined functional analysis of these receptors. Also, advances in crystal structure analysis and cryogenic electron microscopy contribute to the rapid development of our knowledge about structure-function relationships, providing a great starting point for drug development. Despite the progress, questions and challenges remain to fully understand the complexity of the WNT/FZD and Hh/SMO signaling systems. SIGNIFICANCE STATEMENT: The recent years of research have brought about substantial functional and structural insight into mechanisms of activation of Frizzleds and Smoothened. While the advance furthers our mechanistic understanding of ligand recognition, receptor activation, signal specification, and initiation, broader opportunities emerge that allow targeting class F GPCRs for therapy and regenerative medicine employing both biologics and small molecule compounds.
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Affiliation(s)
- Gunnar Schulte
- Karolinska Institutet, Department of Physiology & Pharmacology, Receptor Biology & Signaling, Biomedicum, Stockholm, Sweden
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10
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Grätz L, Voss JH, Schulte G. Class-Wide Analysis of Frizzled-Dishevelled Interactions Using BRET Biosensors Reveals Functional Differences among Receptor Paralogs. ACS Sens 2024; 9:4626-4636. [PMID: 39213612 PMCID: PMC11443525 DOI: 10.1021/acssensors.4c00806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Wingless/Int-1 (WNT) signaling is mediated by WNT binding to 10 Frizzleds (FZD1-10), which propagate the signal inside the cell by interacting with different transducers, most prominently the phosphoprotein Dishevelled (DVL). Despite recent progress, questions about WNT/FZD selectivity and paralog-dependent differences in the FZD/DVL interaction remain unanswered. Here, we present a class-wide analysis of the FZD/DVL interaction using the DEP domain of DVL as a proxy in bioluminescence resonance energy transfer (BRET) techniques. Most FZDs engage in a constitutive high-affinity interaction with DEP. Stimulation of unimolecular FZD/DEP BRET sensors with different ligands revealed that most paralogs are dynamic in the FZD/DEP interface, showing distinct profiles in terms of ligand selectivity and signal kinetics. This study underlines mechanistic differences in terms of how allosteric communication between FZDs and their main signal transducer DVL occurs. Moreover, the unimolecular sensors represent the first receptor-focused biosensors to surpass the requirements for high-throughput screening, facilitating FZD-targeted drug discovery.
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Affiliation(s)
- Lukas Grätz
- Department of Physiology & Pharmacology, Section of Receptor Biology & Signaling, Biomedicum, Karolinska Institutet, S-17165 Stockholm, Sweden
| | - Jan H Voss
- Department of Physiology & Pharmacology, Section of Receptor Biology & Signaling, Biomedicum, Karolinska Institutet, S-17165 Stockholm, Sweden
| | - Gunnar Schulte
- Department of Physiology & Pharmacology, Section of Receptor Biology & Signaling, Biomedicum, Karolinska Institutet, S-17165 Stockholm, Sweden
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11
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Qian Y, Ma Z, Xu Z, Duan Y, Xiong Y, Xia R, Zhu X, Zhang Z, Tian X, Yin H, Liu J, Song J, Lu Y, Zhang A, Guo C, Jin L, Kim WJ, Ke J, Xu F, Huang Z, He Y. Structural basis of Frizzled 4 in recognition of Dishevelled 2 unveils mechanism of WNT signaling activation. Nat Commun 2024; 15:7644. [PMID: 39223191 PMCID: PMC11369211 DOI: 10.1038/s41467-024-52174-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Accepted: 08/28/2024] [Indexed: 09/04/2024] Open
Abstract
WNT signaling is fundamental in development and homeostasis, but how the Frizzled receptors (FZDs) propagate signaling remains enigmatic. Here, we present the cryo-EM structure of FZD4 engaged with the DEP domain of Dishevelled 2 (DVL2), a key WNT transducer. We uncover a distinct binding mode where the DEP finger-loop inserts into the FZD4 cavity to form a hydrophobic interface. FZD4 intracellular loop 2 (ICL2) additionally anchors the complex through polar contacts. Mutagenesis validates the structural observations. The DEP interface is highly conserved in FZDs, indicating a universal mechanism by which FZDs engage with DVLs. We further reveal that DEP mimics G-protein/β-arrestin/GRK to recognize an active conformation of receptor, expanding current GPCR engagement models. Finally, we identify a distinct FZD4 dimerization interface. Our findings delineate the molecular determinants governing FZD/DVL assembly and propagation of WNT signaling, providing long-sought answers underlying WNT signal transduction.
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Affiliation(s)
- Yu Qian
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Zhengxiong Ma
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Zhenmei Xu
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Yaning Duan
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Yangjie Xiong
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Ruixue Xia
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Xinyan Zhu
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Zongwei Zhang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Xinyu Tian
- School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Han Yin
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Jian Liu
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Jing Song
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Yang Lu
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Anqi Zhang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Changyou Guo
- School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Lihua Jin
- Northeast Forestry University, Harbin, China
| | - Woo Jae Kim
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Jiyuan Ke
- Institute of Health and Medicine, Hefei Comprehensive National Science Center, Hefei, China
| | - Fei Xu
- iHuman Institute, ShanghaiTech University, Shanghai, China
| | - Zhiwei Huang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Yuanzheng He
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin, China.
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12
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Zheng S, Sheng R. The emerging understanding of Frizzled receptors. FEBS Lett 2024; 598:1939-1954. [PMID: 38744670 DOI: 10.1002/1873-3468.14903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 04/04/2024] [Accepted: 04/08/2024] [Indexed: 05/16/2024]
Abstract
The Wnt signaling pathway is a huge network governing development and homeostasis, dysregulation of which is associated with a myriad of human diseases. The Frizzled receptor (FZD) family comprises receptors for Wnt ligands, which indispensably mediate Wnt signaling jointly with a variety of co-receptors. Studies of FZDs have revealed that 10 FZD subtypes play diverse roles in physiological processes. At the same time, dysregulation of FZDs is also responsible for various diseases, in particular human cancers. Enormous attention has been paid to the molecular understanding and targeted therapy of FZDs in the past decade. In this review, we summarize the latest research on FZD structure, function, regulation and targeted therapy, providing a basis for guiding future research in this field.
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Affiliation(s)
- Shaoqin Zheng
- College of Life and Health Science, Northeastern University, Shenyang, China
| | - Ren Sheng
- College of Life and Health Science, Northeastern University, Shenyang, China
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13
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Liu H, Yan P, Zhang Z, Han H, Zhou Q, Zheng J, Zhang J, Xu F, Shui W. Structural Mass Spectrometry Captures Residue-Resolved Comprehensive Conformational Rearrangements of a G Protein-Coupled Receptor. J Am Chem Soc 2024; 146:20045-20058. [PMID: 39001877 DOI: 10.1021/jacs.4c03922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/15/2024]
Abstract
G protein-coupled receptor (GPCR) structural studies with in-solution spectroscopic approaches have offered distinctive insights into GPCR activation and signaling that highly complement those yielded from structural snapshots by crystallography or cryo-EM. While most current spectroscopic approaches allow for probing structural changes at selected residues or loop regions, they are not suitable for capturing a holistic view of GPCR conformational rearrangements across multiple domains. Herein, we develop an approach based on limited proteolysis mass spectrometry (LiP-MS) to simultaneously monitor conformational alterations of a large number of residues spanning both flexible loops and structured transmembrane domains for a given GPCR. To benchmark LiP-MS for GPCR conformational profiling, we studied the adenosine 2A receptor (A2AR) in response to different ligand binding (agonist/antagonist/allosteric modulators) and G protein coupling. Systematic and residue-resolved profiling of A2AR conformational rearrangements by LiP-MS precisely captures structural mechanisms in multiple domains underlying ligand engagement, receptor activation, and allostery, and may also reflect local conformational flexibility. Furthermore, these residue-resolution structural fingerprints of the A2AR protein allow us to readily classify ligands of different pharmacology and distinguish the G protein-coupled state. Thus, our study provides a new structural MS approach that would be generalizable to characterizing conformational transition and plasticity for challenging integral membrane proteins.
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Affiliation(s)
- Hongyue Liu
- iHuman Institute, ShanghaiTech University, Shanghai 201210, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pengfei Yan
- iHuman Institute, ShanghaiTech University, Shanghai 201210, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhaoyu Zhang
- iHuman Institute, ShanghaiTech University, Shanghai 201210, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hongbo Han
- University of Chinese Academy of Sciences, Beijing 100049, China
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Qingtong Zhou
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Jie Zheng
- University of Chinese Academy of Sciences, Beijing 100049, China
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jian Zhang
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Fei Xu
- iHuman Institute, ShanghaiTech University, Shanghai 201210, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Wenqing Shui
- iHuman Institute, ShanghaiTech University, Shanghai 201210, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
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14
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Hu L, Chen W, Qian A, Li YP. Wnt/β-catenin signaling components and mechanisms in bone formation, homeostasis, and disease. Bone Res 2024; 12:39. [PMID: 38987555 PMCID: PMC11237130 DOI: 10.1038/s41413-024-00342-8] [Citation(s) in RCA: 56] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 04/27/2024] [Accepted: 05/12/2024] [Indexed: 07/12/2024] Open
Abstract
Wnts are secreted, lipid-modified proteins that bind to different receptors on the cell surface to activate canonical or non-canonical Wnt signaling pathways, which control various biological processes throughout embryonic development and adult life. Aberrant Wnt signaling pathway underlies a wide range of human disease pathogeneses. In this review, we provide an update of Wnt/β-catenin signaling components and mechanisms in bone formation, homeostasis, and diseases. The Wnt proteins, receptors, activators, inhibitors, and the crosstalk of Wnt signaling pathways with other signaling pathways are summarized and discussed. We mainly review Wnt signaling functions in bone formation, homeostasis, and related diseases, and summarize mouse models carrying genetic modifications of Wnt signaling components. Moreover, the therapeutic strategies for treating bone diseases by targeting Wnt signaling, including the extracellular molecules, cytosol components, and nuclear components of Wnt signaling are reviewed. In summary, this paper reviews our current understanding of the mechanisms by which Wnt signaling regulates bone formation, homeostasis, and the efforts targeting Wnt signaling for treating bone diseases. Finally, the paper evaluates the important questions in Wnt signaling to be further explored based on the progress of new biological analytical technologies.
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Affiliation(s)
- Lifang Hu
- Laboratory for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, Key Laboratory for Space Biosciences and Biotechnology, Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China
| | - Wei Chen
- Division in Cellular and Molecular Medicine, Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane University, New Orleans, LA, 70112, USA
| | - Airong Qian
- Laboratory for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, Key Laboratory for Space Biosciences and Biotechnology, Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China.
| | - Yi-Ping Li
- Division in Cellular and Molecular Medicine, Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane University, New Orleans, LA, 70112, USA.
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15
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Schulte G, Scharf MM, Bous J, Voss JH, Grätz L, Kozielewicz P. Frizzleds act as dynamic pharmacological entities. Trends Pharmacol Sci 2024; 45:419-429. [PMID: 38594145 DOI: 10.1016/j.tips.2024.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 03/07/2024] [Accepted: 03/13/2024] [Indexed: 04/11/2024]
Abstract
The Frizzled family of transmembrane receptors (FZD1-10) belongs to the class F of G protein-coupled receptors (GPCRs). FZDs bind to and are activated by Wingless/Int1 (WNT) proteins. The WNT/FZD signaling system regulates crucial aspects of developmental biology and stem-cell regulation. Dysregulation of WNT/FZD communication can lead to developmental defects and diseases such as cancer and fibrosis. Recent insight into the activation mechanisms of FZDs has underlined that protein dynamics and conserved microswitches are essential for FZD-mediated information flow and build the basis for targeting these receptors pharmacologically. In this review, we summarize recent advances in our understanding of FZD activation, and how novel concepts merge and collide with existing dogmas in the field.
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Affiliation(s)
- Gunnar Schulte
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-171 77 Stockholm, Sweden.
| | - Magdalena M Scharf
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-171 77 Stockholm, Sweden
| | - Julien Bous
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-171 77 Stockholm, Sweden
| | - Jan Hendrik Voss
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-171 77 Stockholm, Sweden
| | - Lukas Grätz
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-171 77 Stockholm, Sweden
| | - Pawel Kozielewicz
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-171 77 Stockholm, Sweden
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16
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Dai E, Liu M, Li S, Zhang X, Wang S, Zhao R, He Y, Peng L, Lv L, Xiao H, Yang M, Yang Z, Zhao P. Identification of Novel FZD4 Mutations in Familial Exudative Vitreoretinopathy and Investigating the Pathogenic Mechanisms of FZD4 Mutations. Invest Ophthalmol Vis Sci 2024; 65:1. [PMID: 38558095 PMCID: PMC10996936 DOI: 10.1167/iovs.65.4.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/12/2024] [Indexed: 04/04/2024] Open
Abstract
Purpose The purpose of this study is to report five novel FZD4 mutations identified in familial exudative vitreoretinopathy (FEVR) and to analyze and summarize the pathogenic mechanisms of 34 of 96 reported missense mutations in FZD4. Methods Five probands diagnosed with FEVR and their family members were enrolled in the study. Ocular examinations and targeted gene panel sequencing were conducted on all participants. Plasmids, each carrying 29 previously reported FZD4 missense mutations and five novel mutations, were constructed based on the selection of mutations from each domain of FZD4. These plasmids were used to investigate the effects of mutations on protein expression levels, Norrin/β-catenin activation capacity, membrane localization, norrin binding ability, and DVL2 recruitment ability in HEK293T, HEK293STF, and HeLa cells. Results All five novel mutations (S91F, V103E, C145S, E160K, C377F) responsible for FEVR were found to compromise Norrin/β-catenin activation of FZD4 protein. After reviewing a total of 34 reported missense mutations, we categorized all mutations based on their functional changes: signal peptide mutations, cysteine mutations affecting disulfide bonds, extracellular domain mutations influencing norrin binding, transmembrane domain (TM) 1 and TM7 mutations impacting membrane localization, and intracellular domain mutations affecting DVL2 recruitment. Conclusions We expanded the spectrum of FZD4 mutations relevant to FEVR and experimentally demonstrated that missense mutations in FZD4 can be classified into five categories based on different functional changes.
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Affiliation(s)
- Erkuan Dai
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Min Liu
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Shujin Li
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Xiang Zhang
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shiyuan Wang
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Rulian Zhao
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Yunqi He
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Li Peng
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Liting Lv
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Haodong Xiao
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Mu Yang
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Zhenglin Yang
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Peiquan Zhao
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
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17
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Le V, Abdelmessih G, Dailey WA, Pinnock C, Jobczyk V, Rashingkar R, Drenser KA, Mitton KP. Mechanisms Underlying Rare Inherited Pediatric Retinal Vascular Diseases: FEVR, Norrie Disease, Persistent Fetal Vascular Syndrome. Cells 2023; 12:2579. [PMID: 37947657 PMCID: PMC10647367 DOI: 10.3390/cells12212579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/28/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023] Open
Abstract
Familial Exudative Vitreoretinopathy (FEVR), Norrie disease, and persistent fetal vascular syndrome (PFVS) are extremely rare retinopathies that are clinically distinct but are unified by abnormal retinal endothelial cell function, and subsequent irregular retinal vascular development and/or aberrant inner blood-retinal-barrier (iBRB) function. The early angiogenesis of the retina and its iBRB is a delicate process that is mediated by the canonical Norrin Wnt-signaling pathway in retinal endothelial cells. Pathogenic variants in genes that play key roles within this pathway, such as NDP, FZD4, TSPAN12, and LRP5, have been associated with the incidence of these retinal diseases. Recent efforts to further elucidate the etiology of these conditions have not only highlighted their multigenic nature but have also resulted in the discovery of pathological variants in additional genes such as CTNNB1, KIF11, and ZNF408, some of which operate outside of the Norrin Wnt-signaling pathway. Recent discoveries of FEVR-linked variants in two other Catenin genes (CTNND1, CTNNA1) and the Endoplasmic Reticulum Membrane Complex Subunit-1 gene (EMC1) suggest that we will continue to find additional genes that impact the neural retinal vasculature, especially in multi-syndromic conditions. The goal of this review is to briefly highlight the current understanding of the roles of their encoded proteins in retinal endothelial cells to understand the essential functional mechanisms that can be altered to cause these very rare pediatric retinal vascular diseases.
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Affiliation(s)
- Vincent Le
- Eye Research Institute, Oakland University, Rochester, MI 48309, USA
- Oakland University William Beaumont School of Medicine, Rochester, MI 48309, USA
| | | | - Wendy A. Dailey
- Eye Research Institute, Oakland University, Rochester, MI 48309, USA
| | - Cecille Pinnock
- Eye Research Institute, Oakland University, Rochester, MI 48309, USA
| | - Victoria Jobczyk
- Eye Research Institute, Oakland University, Rochester, MI 48309, USA
| | - Revati Rashingkar
- Oakland University William Beaumont School of Medicine, Rochester, MI 48309, USA
| | - Kimberly A. Drenser
- Eye Research Institute, Oakland University, Rochester, MI 48309, USA
- Associated Retinal Consultants P.C., Royal Oak, MI 48073, USA
| | - Kenneth P. Mitton
- Eye Research Institute, Oakland University, Rochester, MI 48309, USA
- Oakland University William Beaumont School of Medicine, Rochester, MI 48309, USA
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18
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Hong JM, Lee JW, Seen DS, Jeong JY, Huh WK. LPA1-mediated inhibition of CXCR4 attenuates CXCL12-induced signaling and cell migration. Cell Commun Signal 2023; 21:257. [PMID: 37749552 PMCID: PMC10518940 DOI: 10.1186/s12964-023-01261-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 08/09/2023] [Indexed: 09/27/2023] Open
Abstract
BACKGROUND G protein-coupled receptor heteromerization is believed to exert dynamic regulatory impact on signal transduction. CXC chemokine receptor 4 (CXCR4) and its ligand CXCL12, both of which are overexpressed in many cancers, play a pivotal role in metastasis. Likewise, lysophosphatidic acid receptor 1 (LPA1) is implicated in cancer cell proliferation and migration. In our preliminary study, we identified LPA1 as a prospective CXCR4 interactor. In the present study, we investigated in detail the formation of the CXCR4-LPA1 heteromer and characterized the unique molecular features and function of this heteromer. METHODS We employed bimolecular fluorescence complementation, bioluminescence resonance energy transfer, and proximity ligation assays to demonstrate heteromerization between CXCR4 and LPA1. To elucidate the distinctive molecular characteristics and functional implications of the CXCR4-LPA1 heteromer, we performed various assays, including cAMP, BRET for G protein activation, β-arrestin recruitment, ligand binding, and transwell migration assays. RESULTS We observed that CXCR4 forms heteromers with LPA1 in recombinant HEK293A cells and the human breast cancer cell line MDA-MB-231. Coexpression of LPA1 with CXCR4 reduced CXCL12-mediated cAMP inhibition, ERK activation, Gαi/o activation, and β-arrestin recruitment, while CXCL12 binding to CXCR4 remained unaffected. In contrast, CXCR4 had no impact on LPA1-mediated signaling. The addition of lysophosphatidic acid (LPA) further hindered CXCL12-induced Gαi/o recruitment to CXCR4. LPA or alkyl-OMPT inhibited CXCL12-induced migration in various cancer cells that endogenously express both CXCR4 and LPA1. Conversely, CXCL12-induced calcium signaling and migration were increased in LPAR1 knockout cells, and LPA1-selective antagonists enhanced CXCL12-induced Gαi/o signaling and cell migration in the parental MDA-MB-231 cells but not in LPA1-deficient cells. Ultimately, complete inhibition of cell migration toward CXCL12 and alkyl-OMPT was only achieved in the presence of both CXCR4 and LPA1 antagonists. CONCLUSIONS The presence and impact of CXCR4-LPA1 heteromers on CXCL12-induced signaling and cell migration have been evidenced across various cell lines. This discovery provides crucial insights into a valuable regulatory mechanism of CXCR4 through heteromerization. Moreover, our findings propose a therapeutic potential in combined CXCR4 and LPA1 inhibitors for cancer and inflammatory diseases associated with these receptors, simultaneously raising concerns about the use of LPA1 antagonists alone for such conditions. Video Abstract.
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Affiliation(s)
- Jong Min Hong
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jin-Woo Lee
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Dong-Seung Seen
- GPCR Therapeutics Inc, Gwanak-Gu, Seoul, 08790, Republic of Korea
| | - Jae-Yeon Jeong
- GPCR Therapeutics Inc, Gwanak-Gu, Seoul, 08790, Republic of Korea.
| | - Won-Ki Huh
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
- Institute of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea.
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19
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Ding J, Lee SJ, Vlahos L, Yuki K, Rada CC, van Unen V, Vuppalapaty M, Chen H, Sura A, McCormick AK, Tomaske M, Alwahabi S, Nguyen H, Nowatzke W, Kim L, Kelly L, Vollrath D, Califano A, Yeh WC, Li Y, Kuo CJ. Therapeutic blood-brain barrier modulation and stroke treatment by a bioengineered FZD 4-selective WNT surrogate in mice. Nat Commun 2023; 14:2947. [PMID: 37268690 PMCID: PMC10238527 DOI: 10.1038/s41467-023-37689-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 03/27/2023] [Indexed: 06/04/2023] Open
Abstract
Derangements of the blood-brain barrier (BBB) or blood-retinal barrier (BRB) occur in disorders ranging from stroke, cancer, diabetic retinopathy, and Alzheimer's disease. The Norrin/FZD4/TSPAN12 pathway activates WNT/β-catenin signaling, which is essential for BBB and BRB function. However, systemic pharmacologic FZD4 stimulation is hindered by obligate palmitoylation and insolubility of native WNTs and suboptimal properties of the FZD4-selective ligand Norrin. Here, we develop L6-F4-2, a non-lipidated, FZD4-specific surrogate which significantly improves subpicomolar affinity versus native Norrin. In Norrin knockout (NdpKO) mice, L6-F4-2 not only potently reverses neonatal retinal angiogenesis deficits, but also restores BRB and BBB function. In adult C57Bl/6J mice, post-stroke systemic delivery of L6-F4-2 strongly reduces BBB permeability, infarction, and edema, while improving neurologic score and capillary pericyte coverage. Our findings reveal systemic efficacy of a bioengineered FZD4-selective WNT surrogate during ischemic BBB dysfunction, with potential applicability to adult CNS disorders characterized by an aberrant blood-brain barrier.
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Affiliation(s)
- Jie Ding
- Department of Medicine, Division of Hematology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Sung-Jin Lee
- Surrozen, Inc. South San Francisco, South San Francisco, CA, 94080, USA
| | - Lukas Vlahos
- Department of Systems Biology, Columbia University, Columbia, NY, 10032, USA
| | - Kanako Yuki
- Department of Medicine, Division of Hematology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Cara C Rada
- Department of Medicine, Division of Hematology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Vincent van Unen
- Department of Medicine, Division of Hematology, Stanford University School of Medicine, Stanford, CA, 94305, USA
- Institute for Immunity, Transplantation and Infection, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | | | - Hui Chen
- Surrozen, Inc. South San Francisco, South San Francisco, CA, 94080, USA
| | - Asmiti Sura
- Surrozen, Inc. South San Francisco, South San Francisco, CA, 94080, USA
| | - Aaron K McCormick
- Department of Medicine, Division of Hematology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Madeline Tomaske
- Department of Medicine, Division of Hematology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Samira Alwahabi
- Department of Medicine, Division of Hematology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Huy Nguyen
- Surrozen, Inc. South San Francisco, South San Francisco, CA, 94080, USA
| | - William Nowatzke
- Surrozen, Inc. South San Francisco, South San Francisco, CA, 94080, USA
| | - Lily Kim
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Lisa Kelly
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Douglas Vollrath
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Andrea Califano
- Department of Systems Biology, Columbia University, Columbia, NY, 10032, USA
| | - Wen-Chen Yeh
- Surrozen, Inc. South San Francisco, South San Francisco, CA, 94080, USA
| | - Yang Li
- Surrozen, Inc. South San Francisco, South San Francisco, CA, 94080, USA
| | - Calvin J Kuo
- Department of Medicine, Division of Hematology, Stanford University School of Medicine, Stanford, CA, 94305, USA.
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20
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Bowin CF, Kozielewicz P, Grätz L, Kowalski-Jahn M, Schihada H, Schulte G. WNT stimulation induces dynamic conformational changes in the Frizzled-Dishevelled interaction. Sci Signal 2023; 16:eabo4974. [PMID: 37014927 DOI: 10.1126/scisignal.abo4974] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2023]
Abstract
Frizzleds (FZDs) are G protein-coupled receptors (GPCRs) that bind to WNT family ligands. FZDs signal through multiple effector proteins, including Dishevelled (DVL), which acts as a hub for several downstream signaling pathways. To understand how WNT binding to FZD stimulates intracellular signaling and influences downstream pathway selectivity, we investigated the dynamic changes in the FZD5-DVL2 interaction elicited by WNT-3A and WNT-5A. Ligand-induced changes in bioluminescence resonance energy transfer (BRET) between FZD5 and DVL2 or the isolated FZD-binding DEP domain of DVL2 revealed a composite response consisting of both DVL2 recruitment and conformational dynamics in the FZD5-DVL2 complex. The combination of different BRET paradigms enabled us to identify ligand-dependent conformational dynamics in the FZD5-DVL2 complex and distinguish them from ligand-induced recruitment of DVL2 or DEP to FZD5. The observed agonist-induced conformational changes at the receptor-transducer interface suggest that extracellular agonist and intracellular transducers cooperate through transmembrane allosteric interaction with FZDs in a ternary complex reminiscent of that of classical GPCRs.
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Affiliation(s)
- Carl-Fredrik Bowin
- Department of Physiology and Pharmacology, Section of Receptor Biology and Signaling, Karolinska Institutet, Stockholm, Sweden
| | - Pawel Kozielewicz
- Department of Physiology and Pharmacology, Section of Receptor Biology and Signaling, Karolinska Institutet, Stockholm, Sweden
| | - Lukas Grätz
- Department of Physiology and Pharmacology, Section of Receptor Biology and Signaling, Karolinska Institutet, Stockholm, Sweden
| | - Maria Kowalski-Jahn
- Department of Physiology and Pharmacology, Section of Receptor Biology and Signaling, Karolinska Institutet, Stockholm, Sweden
| | - Hannes Schihada
- Department of Physiology and Pharmacology, Section of Receptor Biology and Signaling, Karolinska Institutet, Stockholm, Sweden
| | - Gunnar Schulte
- Department of Physiology and Pharmacology, Section of Receptor Biology and Signaling, Karolinska Institutet, Stockholm, Sweden
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21
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Zheng S, Lin J, Pang Z, Zhang H, Wang Y, Ma L, Zhang H, Zhang X, Chen M, Zhang X, Zhao C, Qi J, Cao L, Wang M, He X, Sheng R. Aberrant Cholesterol Metabolism and Wnt/β-Catenin Signaling Coalesce via Frizzled5 in Supporting Cancer Growth. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2200750. [PMID: 35975457 PMCID: PMC9534957 DOI: 10.1002/advs.202200750] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 07/23/2022] [Indexed: 05/12/2023]
Abstract
Frizzled (Fzd) proteins are Wnt receptors and play essential roles in development, homeostasis, and oncogenesis. How Wnt/Fzd signaling is coupled to physiological regulation remains unknown. Cholesterol is reported as a signaling molecule regulating morphogen such as Hedgehog signaling. Despite the elusiveness of the in-depth mechanism, it is well-established that pancreatic cancer specially requires abnormal cholesterol metabolism levels for growth. In this study, it is unexpectedly found that among ten Fzds, Fzd5 has a unique capacity to bind cholesterol specifically through its conserved extracellular linker region. Cholesterol-binding enables Fzd5 palmitoylation, which is indispensable for receptor maturation and trafficking to the plasma membrane. In Wnt-addicted pancreatic ductal adenocarcinoma (PDAC), cholesterol stimulates tumor growth via Fzd5-mediated Wnt/β-catenin signaling. A natural oxysterol, 25-hydroxylsterol competes with cholesterol and inhibits Fzd5 maturation and Wnt signaling, thereby alleviating PDAC growth. This cholesterol-receptor interaction and ensuing receptor lipidation uncover a novel mechanism by which Fzd5 acts as a cholesterol sensor and pivotal connection coupling lipid metabolism to morphogen signaling. These findings further suggest that cholesterol-targeting may provide new therapeutic opportunities for treating Wnt-dependent cancers.
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Affiliation(s)
- Shaoqin Zheng
- College of Life and Health ScienceNortheastern UniversityShenyang110819P. R. China
| | - Jiahui Lin
- College of Life and Health ScienceNortheastern UniversityShenyang110819P. R. China
| | - Zhongqiu Pang
- College of Life and Health ScienceNortheastern UniversityShenyang110819P. R. China
| | - Hui Zhang
- College of Life and Health ScienceNortheastern UniversityShenyang110819P. R. China
| | - Yinuo Wang
- College of Life and Health ScienceNortheastern UniversityShenyang110819P. R. China
| | - Lanjing Ma
- College of Life and Health ScienceNortheastern UniversityShenyang110819P. R. China
| | - Haijiao Zhang
- College of Life and Health ScienceNortheastern UniversityShenyang110819P. R. China
| | - Xi Zhang
- College of SciencesNortheastern UniversityShenyang110004P. R. China
| | - Maorong Chen
- F.M Kirby Neurobiology CenterBoston Children's HospitalDepartment of NeurologyHarvard Medical SchoolBostonMA02115USA
| | - Xinjun Zhang
- Key Laboratory of Molecular Biophysics of the Ministry of EducationNational Engineering Research Center for NanomedicineCollege of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan430074P. R. China
| | - Chao Zhao
- School of Public HealthJilin UniversityChangchun130021P. R. China
| | - Jun Qi
- Department of Cancer BiologyDana‐Farber Cancer InstituteDepartment of MedicineHarvard Medical SchoolBostonMA02215USA
| | - Liu Cao
- Institute of Translational MedicineKey Laboratory of Cell Biology of Ministry of Public Healthand Key Laboratory of Medical Cell Biology of Ministry of EducationLiaoning Province Collaborative Innovation Center of Aging Related Disease Diagnosis and Treatment and PreventionChina Medical UniversityShenyang110112P. R. China
| | - Min Wang
- Department of Biliary‐Pancreatic SurgeryAffiliated Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology1095 Jiefang AveWuhan430030P. R. China
| | - Xi He
- F.M Kirby Neurobiology CenterBoston Children's HospitalDepartment of NeurologyHarvard Medical SchoolBostonMA02115USA
| | - Ren Sheng
- College of Life and Health ScienceNortheastern UniversityShenyang110819P. R. China
- F.M Kirby Neurobiology CenterBoston Children's HospitalDepartment of NeurologyHarvard Medical SchoolBostonMA02115USA
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22
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van der Ende SR, Meyers BS, Capasso JE, Sasongko M, Yonekawa Y, Pihlblad M, Huey J, Bedoukian EC, Krantz ID, Ngo MH, McMaster CR, Levin AV, Robitaille JM. Severe Familial Exudative Vitreoretinopathy, Congenital Hearing Loss, and Developmental Delay in a Child With Biallelic Variants in FZD4. JAMA Ophthalmol 2022; 140:889-893. [PMID: 35951321 PMCID: PMC9372905 DOI: 10.1001/jamaophthalmol.2022.2914] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Question Are FZD4 variants associated with familial exudative vitreoretinopathy (FEVR) with extraocular features? Findings This case series included a patient with biallelic FZD4 variants with severe FEVR in infancy, congenital hearing loss, and developmental delay. Each parent was carrying 1 of the alleles and manifested mild FEVR; cell-based FZD4 receptor-activation assays determined that FZD4 function was dramatically decreased in the presence of these compound heterozygous variants. Meaning Biallelic variants in FZD4 can result in a severe ocular phenotype with systemic features, which may represent a novel syndrome. Importance Familial exudative vitreoretinopathy (FEVR) is a nonsyndromic autosomal dominant retinal disorder commonly caused by variants in the FZD4 gene. This study investigates the potential role beyond ocular abnormalities for FZD4 gene variants in patients with FEVR. Objective To evaluate the role of FZD4 in symptoms beyond those associated with FEVR through a patient with biallelic variants in FZD4. Design, Setting, and Participants This case series included the DNA testing and phenotyping of 1 patient proband and her parents, combined with signaling assays, to determine the association of patient-derived compound heterozygous variants on FZD4 signaling and biologic function. Main Outcomes and Measures FZD4 genes were tested using next-generation sequencing and Sanger sequencing. Cell-based assays measured the effect of the variants on FZD4 signaling. Results The proband presented with absent red reflexes from complete tractional retinal detachments diagnosed at 3 days of age and failed the newborn screening hearing test. Auditory brainstem response at 6 months of age showed bilateral mild to moderate high-frequency sensorineural hearing loss. The patient manifested developmental delays in speech and walking. Intravenous fluorescein angiography (IVFA) of the patient’s parents detected stage 1 FEVR. Genetic testing revealed 2 FZD4 variants in the patient, each variant found in 1 parent. Signaling assays confirmed that the presence of both variants was associated with significantly worse signaling activity compared with the heterozygous state. Conclusions and Relevance Results of this case series suggest that extraocular syndromic FEVR was associated with FZD4 variants. The decrease in FZD4 signaling owing to the biallelic nature of the disease resulted in hearing deficits, developmental delays, and a more severe retinal phenotype.
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Affiliation(s)
- Sarah R van der Ende
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Benjamin S Meyers
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Jenina E Capasso
- Pediatric Ophthalmology and Ocular Genetics, Flaum Eye Institute, University of Rochester, Rochester, New York.,Pediatric Genetics, Golisano Children's Hospital, University of Rochester, Rochester, New York
| | | | - Yoshihiro Yonekawa
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania.,Wills Eye Hospital, Philadelphia, Pennsylvania
| | - Matthew Pihlblad
- Pediatric Ophthalmology and Strabismus, UPMC Children's Hospital of Pittsburgh, Pennsylvania
| | - Jennifer Huey
- Pediatric Ophthalmology and Strabismus, UPMC Children's Hospital of Pittsburgh, Pennsylvania.,Laboratory of Medicine and Pathology, University of Washington Medical Center, Seattle
| | - Emma C Bedoukian
- Roberts Individualized Medical Genetics Center, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Ian D Krantz
- Roberts Individualized Medical Genetics Center, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Michael H Ngo
- Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Christopher R McMaster
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Alex V Levin
- Pediatric Ophthalmology and Ocular Genetics, Flaum Eye Institute, University of Rochester, Rochester, New York
| | - Johane M Robitaille
- Department of Ophthalmology & Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
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23
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Mahoney JP, Bruguera ES, Vasishtha M, Killingsworth LB, Kyaw S, Weis WI. PI(4,5)P 2-stimulated positive feedback drives the recruitment of Dishevelled to Frizzled in Wnt-β-catenin signaling. Sci Signal 2022; 15:eabo2820. [PMID: 35998232 PMCID: PMC9528458 DOI: 10.1126/scisignal.abo2820] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In the Wnt-β-catenin pathway, Wnt binding to Frizzled (Fzd) and LRP5 or LRP6 (LRP5/6) co-receptors inhibits the degradation of the transcriptional coactivator β-catenin by recruiting the cytosolic effector Dishevelled (Dvl). Polymerization of Dvl at the plasma membrane recruits the β-catenin destruction complex, enabling the phosphorylation of LRP5/6, a key step in inhibiting β-catenin degradation. Using purified Fzd proteins reconstituted in lipid nanodiscs, we investigated the factors that promote the recruitment of Dvl to the plasma membrane. We found that the affinity of Fzd for Dvl was not affected by Wnt ligands, in contrast to other members of the GPCR superfamily for which the binding of extracellular ligands affects the affinity for downstream transducers. Instead, Fzd-Dvl binding was enhanced by increased concentration of the lipid PI(4,5)P2, which is generated by Dvl-associated lipid kinases in response to Wnt and which is required for LRP5/6 phosphorylation. Moreover, binding to Fzd did not promote Dvl DEP domain dimerization, which has been proposed to be required for signaling downstream of Fzd. Our findings suggest a positive feedback loop in which Wnt-stimulated local PI(4,5)P2 production enhances Dvl recruitment and further PI(4,5)P2 production to support Dvl polymerization, LRP5/6 phosphorylation, and β-catenin stabilization.
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Affiliation(s)
- Jacob P Mahoney
- Departments of Structural Biology and Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - Elise S Bruguera
- Departments of Structural Biology and Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - Mansi Vasishtha
- Departments of Structural Biology and Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - Lauren B Killingsworth
- Departments of Structural Biology and Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - Saw Kyaw
- Departments of Structural Biology and Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - William I Weis
- Departments of Structural Biology and Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94035, USA
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24
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Ko SB, Mihara E, Park Y, Roh K, Kang C, Takagi J, Bang I, Choi HJ. Functional role of the Frizzled linker domain in the Wnt signaling pathway. Commun Biol 2022; 5:421. [PMID: 35513706 PMCID: PMC9072438 DOI: 10.1038/s42003-022-03370-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 04/14/2022] [Indexed: 12/20/2022] Open
Abstract
The Wnt signaling pathway plays a critical role in the developmental and physiological processes of metazoans. We previously reported that the Frizzled4 (FZD4) linker domain plays an important role in Norrin binding and signaling. However, the question remains whether the FZD linker contributes to Wnt signaling in general. Here, we show that the FZD linker is involved in Wnt binding and affects downstream Wnt signaling. A FZD4 chimera, in which the linker was swapped with that of the non-canonical receptor FZD6, impairs the binding with WNT3A and suppresses the recruitment of LRP6 and Disheveled, resulting in reduced canonical signaling. A similar effect was observed for non-canonical signaling. A FZD6 chimera containing the FZD1 linker showed reduced WNT5A binding and impaired signaling in ERK, JNK, and AKT mediated pathways. Altogether, our results suggest that the FZD linker plays an important role in specific Wnt binding and intracellular Wnt signaling.
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Affiliation(s)
- Seung-Bum Ko
- Department of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Emiko Mihara
- Laboratory for Protein Synthesis and Expression, Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Yedarm Park
- Department of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kyeonghwan Roh
- Department of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Chanhee Kang
- Department of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Junichi Takagi
- Laboratory for Protein Synthesis and Expression, Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Injin Bang
- Department of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
- Laura and Isaac Perlmutter Cancer Center, New York University Langone Medical Center, New York, 10016, NY, USA.
| | - Hee-Jung Choi
- Department of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
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25
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Employing Genetically Encoded, Biophysical Sensors to Understand WNT/Frizzled Interaction and Receptor Complex Activation. Handb Exp Pharmacol 2021. [PMID: 34463848 DOI: 10.1007/164_2021_534] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/15/2025]
Abstract
The Frizzled (FZD) family of WNT receptors consists of ten paralogues in mammals. They belong to the superfamily of G protein-coupled receptors and regulate crucial processes during embryonic development. Dysregulated FZD signaling leads to disease, most prominently to diverse forms of cancer, which renders these receptors attractive for drug discovery. Recent advances in assay development and the design of genetically encoded biosensors monitoring ligand-receptor interaction, conformational dynamics, and protein-protein interaction have allowed for a better pharmacological understanding of WNT/FZD signal transduction and open novel avenues for mechanism-based drug discovery and screening. In this chapter, we summarize the recent progress in the molecular dissection of FZD activation based on advanced biosensors.
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26
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Ji Y, Wang T, Gao Q, Huang X, Chang J. Normalization of non-canonical Wnt signalings does not compromise blood-brain barrier protection conferred by upregulating endothelial Wnt/β-catenin signaling following ischemic stroke. CNS Neurosci Ther 2021; 27:1085-1096. [PMID: 34056869 PMCID: PMC8339534 DOI: 10.1111/cns.13661] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 05/05/2021] [Accepted: 05/06/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Endothelial canonical (Wnt/β-catenin) and non-canonical Wnt signalings (Wnt/PCP and Wnt/Ca2+ ) promote blood-brain barrier (BBB) development and antagonize each other. However, the effects of ischemic stroke on endothelial canonical and non-canonical Wnt signalings are unclear. Further, how non-canonical Wnt signalings are influenced by upregulation of endothelial Wnt/β-catenin signaling and subsequently affect BBB function following ischemic stroke have not been studied. METHODS First, we determined the levels of Wnt signaling markers including TCF/LEF1 transcription activity, Axin2 mRNA, phospho-JNKThr183/Tyr185 , and NFAT in brain endothelial cells (ECs) with the deletion of Wnt receptor Frizzled (Fzd)4 or Fzd6, the two most abundant Fzds in brain ECs. Next, we observed the effect of ischemia/reperfusion injury on Wnt signalings in brain ECs and adult mice. Last, we assessed the changes of non-canonical Wnt signalings and BBB injury in the early stage of ischemic stroke in mice with endothelial β-catenin activation (β-cat mice). RESULTS Fzd4 or Fzd6 deletion dampened both Wnt/β-catenin and Wnt/PCP signalings but enhanced Wnt/Ca2+ signaling in brain ECs. Both canonical and non-canonical Wnt signalings in brain ECs were downregulated after ischemia/reperfusion injury in vitro and in vivo. Upregulating endothelial Wnt/β-catenin signaling in β-cat mice normalized the downregulated non-canonical Wnt signalings, which did not compromise its protective effects on BBB integrity and endothelial tight junction following ischemic stroke. CONCLUSIONS The BBB protection induced by upregulation of endothelial Wnt/β-catenin signaling may be not interfered by the normalization of non-canonical Wnt signalings in the early stage of ischemic stroke.
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Affiliation(s)
- Ya‐bin Ji
- Shenzhen Key Laboratory of Biomimetic Materials and Cellular ImmunomodulationInstitute of Biomedicine and BiotechnologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenChina
- Department of NeurologyNanfang HospitalSouthern Medical UniversityGuangzhouChina
- Baiyun affiliated Cerebrovascular HospitalNanfang Hospital Baiyun BranchSouthern Medical UniversityGuangzhouChina
| | - Tian‐xi Wang
- Shenzhen Key Laboratory of Biomimetic Materials and Cellular ImmunomodulationInstitute of Biomedicine and BiotechnologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenChina
| | - Qiang Gao
- Shenzhen Key Laboratory of Biomimetic Materials and Cellular ImmunomodulationInstitute of Biomedicine and BiotechnologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenChina
- Department of NeurosurgeryThe First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouChina
| | - Xiao‐wen Huang
- Shenzhen Key Laboratory of Biomimetic Materials and Cellular ImmunomodulationInstitute of Biomedicine and BiotechnologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenChina
| | - Junlei Chang
- Shenzhen Key Laboratory of Biomimetic Materials and Cellular ImmunomodulationInstitute of Biomedicine and BiotechnologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenChina
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27
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Kozielewicz P, Shekhani R, Moser S, Bowin CF, Wesslowski J, Davidson G, Schulte G. Quantitative Profiling of WNT-3A Binding to All Human Frizzled Paralogues in HEK293 Cells by NanoBiT/BRET Assessments. ACS Pharmacol Transl Sci 2021; 4:1235-1245. [PMID: 34151213 PMCID: PMC8205236 DOI: 10.1021/acsptsci.1c00084] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Indexed: 02/06/2023]
Abstract
![]()
The WNT signaling
system governs critical processes during embryonic
development and tissue homeostasis, and its dysfunction can lead to
cancer. Details concerning selectivity and differences in relative
binding affinities of 19 mammalian WNTs to the cysteine-rich domain
(CRD) of their receptors—the ten mammalian Frizzleds (FZDs)—remain
unclear. Here, we used eGFP-tagged mouse WNT-3A for a systematic analysis
of WNT interaction with every human FZD paralogue in HEK293A cells.
Employing HiBiT-tagged full-length FZDs, we studied eGFP-WNT-3A binding
kinetics, saturation binding, and competition binding with commercially
available WNTs in live HEK293A cells using a NanoBiT/BRET-based assay.
Further, we generated receptor chimeras to dissect the contribution
of the transmembrane core to WNT-CRD binding. Our data pinpoint distinct
WNT-FZD selectivity and shed light on the complex WNT-FZD binding
mechanism. The methodological development described herein reveals
yet unappreciated details of the complexity of WNT signaling and WNT-FZD
interactions, providing further details with respect to WNT-FZD selectivity.
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Affiliation(s)
- Paweł Kozielewicz
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
| | - Rawan Shekhani
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
| | - Stefanie Moser
- Institute of Biological and Chemical Systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), 76131, Karlsruhe, Germany
| | - Carl-Fredrik Bowin
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
| | - Janine Wesslowski
- Institute of Biological and Chemical Systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), 76131, Karlsruhe, Germany
| | - Gary Davidson
- Institute of Biological and Chemical Systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), 76131, Karlsruhe, Germany
| | - Gunnar Schulte
- Section of Receptor Biology & Signaling, Dept. Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
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28
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Marakhonov AV, Mishina IA, Kadyshev VV, Repina SA, Shurygina MF, Shchagina OA, Vasserman NN, Vasilyeva TA, Kutsev SI, Zinchenko RA. Prenatal diagnosis of Norrie disease after whole exome sequencing of an affected proband during an ongoing pregnancy: a case report. BMC MEDICAL GENETICS 2020; 21:156. [PMID: 33092543 PMCID: PMC7579785 DOI: 10.1186/s12881-020-01093-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 11/29/2022]
Abstract
Background Hereditary ophthalmic pathology is a genetically heterogeneous group of diseases that occur either as an isolated eye disorder or as a symptom of hereditary syndromes (chromosomal or monogenic). Thus, a diagnostic search in some cases of ophthalmic pathology can be time- and cost-consuming. The most challenging situation can arise when prenatal diagnosis is needed during an ongoing pregnancy. Case presentation A family was referred to the Research Centre for Medical Genetics (RCMG) for childbirth risk prognosis at 7–8 week of gestation because a previous child, a six-year-old boy, has congenital aniridia, glaucoma, retinal detachment, severe psychomotor delay, and lack of speech and has had several ophthalmic surgeries. The affected child had been previously tested for PAX6 mutations and 11p13 copy number variations, which revealed no changes. Considering the lack of pathogenic changes and precise diagnosis for the affected boy, NGS sequencing of clinically relevant genes was performed for the ongoing pregnancy; it revealed a novel hemizygous substitution NM_000266.3(NDP):c.385G > T, p.(Glu129*), in the NDP gene, which is associated with Norrie disease (OMIM #310600). Subsequent Sanger validation of the affected boy and his mother confirmed the identified substitution inherited in X-linked recessive mode. Amniotic fluid testing revealed the fetus was hemizygous for the variant and lead to the decision of the family to interrupt the pregnancy. Complications which developed during the termination of pregnancy required hysterectomy due to medical necessity. Conclusions Clinical polymorphism of hereditary ophthalmic pathology can severely complicate establishment of an exact diagnosis and make it time- and cost-consuming. NGS appears to be the method-of-choice in complicated cases, and this could substantially hasten the establishment of a diagnosis and genetic risk estimation.
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Affiliation(s)
- Andrey V Marakhonov
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation.
| | - Irina A Mishina
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Vitaly V Kadyshev
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Svetlana A Repina
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Maria F Shurygina
- S. Fyodorov Eye Microsurgery Federal State Institution, Moscow, Russian Federation
| | - Olga A Shchagina
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Natalya N Vasserman
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Tatyana A Vasilyeva
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Sergey I Kutsev
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation
| | - Rena A Zinchenko
- Laboratory of Genetic Epidemiology, Research Centre for Medical Genetics, Moscow, Russian Federation.,N.A. Semashko National Research Institute of Public Health, Moscow, Russian Federation
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29
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Tsutsumi N, Mukherjee S, Waghray D, Janda CY, Jude KM, Miao Y, Burg JS, Aduri NG, Kossiakoff AA, Gati C, Garcia KC. Structure of human Frizzled5 by fiducial-assisted cryo-EM supports a heterodimeric mechanism of canonical Wnt signaling. eLife 2020; 9:e58464. [PMID: 32762848 PMCID: PMC7442489 DOI: 10.7554/elife.58464] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 08/06/2020] [Indexed: 01/19/2023] Open
Abstract
Frizzleds (Fzd) are the primary receptors for Wnt morphogens, which are essential regulators of stem cell biology, yet the structural basis of Wnt signaling through Fzd remains poorly understood. Here we report the structure of an unliganded human Fzd5 determined by single-particle cryo-EM at 3.7 Å resolution, with the aid of an antibody chaperone acting as a fiducial marker. We also analyzed the topology of low-resolution XWnt8/Fzd5 complex particles, which revealed extreme flexibility between the Wnt/Fzd-CRD and the Fzd-TM regions. Analysis of Wnt/β-catenin signaling in response to Wnt3a versus a 'surrogate agonist' that cross-links Fzd to LRP6, revealed identical structure-activity relationships. Thus, canonical Wnt/β-catenin signaling appears to be principally reliant on ligand-induced Fzd/LRP6 heterodimerization, versus the allosteric mechanisms seen in structurally analogous class A G protein-coupled receptors, and Smoothened. These findings deepen our mechanistic understanding of Wnt signal transduction, and have implications for harnessing Wnt agonism in regenerative medicine.
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Affiliation(s)
- Naotaka Tsutsumi
- Department of Molecular and Cellular Physiology, Stanford University School of MedicineStanfordUnited States
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
- Howard Hughes Medical Institute, Stanford University School of MedicineStanfordUnited States
| | - Somnath Mukherjee
- Department of Biochemistry and Molecular Biology, The University of ChicagoChicagoUnited States
| | - Deepa Waghray
- Department of Molecular and Cellular Physiology, Stanford University School of MedicineStanfordUnited States
| | - Claudia Y Janda
- Department of Molecular and Cellular Physiology, Stanford University School of MedicineStanfordUnited States
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
- Princess Máxima Center for Pediatric OncologyUtrechtNetherlands
| | - Kevin M Jude
- Department of Molecular and Cellular Physiology, Stanford University School of MedicineStanfordUnited States
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
- Howard Hughes Medical Institute, Stanford University School of MedicineStanfordUnited States
| | - Yi Miao
- Department of Molecular and Cellular Physiology, Stanford University School of MedicineStanfordUnited States
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
| | - John S Burg
- Department of Molecular and Cellular Physiology, Stanford University School of MedicineStanfordUnited States
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
| | - Nanda Gowtham Aduri
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
- SLAC National Accelerator Laboratory, Bioscience DivisionMenlo ParkUnited States
| | - Anthony A Kossiakoff
- Department of Biochemistry and Molecular Biology, The University of ChicagoChicagoUnited States
| | - Cornelius Gati
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
- SLAC National Accelerator Laboratory, Bioscience DivisionMenlo ParkUnited States
| | - K Christopher Garcia
- Department of Molecular and Cellular Physiology, Stanford University School of MedicineStanfordUnited States
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
- Howard Hughes Medical Institute, Stanford University School of MedicineStanfordUnited States
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30
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Aubert-Mucca M, Pernin-Grandjean J, Marchasson S, Gaston V, Habib C, Meunier I, Sigaudy S, Kaplan J, Roche O, Denis D, Bitoun P, Haye D, Verloes A, Calvas P, Chassaing N, Plaisancié J. Confirmation of FZD5 implication in a cohort of 50 patients with ocular coloboma. Eur J Hum Genet 2020; 29:131-140. [PMID: 32737437 DOI: 10.1038/s41431-020-0695-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 07/01/2020] [Accepted: 07/07/2020] [Indexed: 11/09/2022] Open
Abstract
Defects in optic fissure closure can lead to congenital ocular coloboma. This ocular malformation, often associated with microphthalmia, is described in various clinical forms with different inheritance patterns and genetic heterogeneity. In recent times, the identification of an increased number of genes involved in numerous cellular functions has led to a better understanding in optic fissure closure mechanisms. Nevertheless, most of these genes are also involved in wider eye growth defects such as micro-anophthalmia, questioning the mechanisms controlling both extension and severity of optic fissure closure defects. However, some genes, such as FZD5, have only been so far identified in isolated coloboma. Thus, to estimate the frequency of implication of different ocular genes, we screened a cohort of 50 patients affected by ocular coloboma by using targeted sequencing of 119 genes involved in ocular development. This analysis revealed seven heterozygous (likely) pathogenic variants in RARB, MAB21L2, RBP4, TFAP2A, and FZD5. Surprisingly, three out of the seven variants detected herein were novel disease-causing variants in FZD5 identified in three unrelated families with dominant inheritance. Although molecular diagnosis rate remains relatively low in patients with ocular coloboma (14% (7/50) in this work), these results, however, highlight the importance of genetic screening, especially of FZD5, in such patients. Indeed, in our series, FZD5 variants represent half of the genetic causes, constituting 6% (3/50) of the patients who benefited from a molecular diagnosis. Our findings support the involvement of FZD5 in ocular coloboma and provide clues for screening this gene during current diagnostic procedures.
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Affiliation(s)
- Marion Aubert-Mucca
- Service de Génétique Médicale, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | | | | | - Veronique Gaston
- Service de Génétique Médicale, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Christophe Habib
- Service de Génétique Médicale, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Isabelle Meunier
- Centre de Référence des Maladies Sensorielles Génétiques, Hôpital Gui de Chauliac, Institut de Neurosciences de Montpellier, INSERM U1051, Université de Montpellier, Montpellier, France
| | - Sabine Sigaudy
- Département de Génétique Médicale, AP-HM, CHU Timone Enfants, Marseille, France
| | - Josseline Kaplan
- Laboratoire de Génétique Ophtalmologique, INSERM U1163 Institut Imagine, Paris, France
| | - Olivier Roche
- Département d'Ophtalmologie, IHU Necker-Enfants-Malades, Université Paris-Descartes, Paris, France
| | - Danièle Denis
- Institut de Neurosciences de la Timone (INT), Centre National de la Recherche Scientifique (CNRS), Aix-Marseille Université (AMU), Marseille, France
| | - Pierre Bitoun
- Département d'Ophtalmologie, SIDVA 91, Juvisy-sur-Orge, France
| | - Damien Haye
- Département de Génétique, Hôpital Robert Debré, Paris, France
| | - Alain Verloes
- Département de Génétique, Hôpital Robert Debré, Paris, France
| | - Patrick Calvas
- Service de Génétique Médicale, Hôpital Purpan, CHU Toulouse, Toulouse, France.,INSERM U1056, UDEAR, Equipe 4, Université Toulouse III, Toulouse, France.,Centre de Référence des Affections Rares en Génétique Ophtalmologique CARGO, Site Constitutif, CHU Toulouse, Toulouse, France
| | - Nicolas Chassaing
- Service de Génétique Médicale, Hôpital Purpan, CHU Toulouse, Toulouse, France.,INSERM U1056, UDEAR, Equipe 4, Université Toulouse III, Toulouse, France.,Centre de Référence des Affections Rares en Génétique Ophtalmologique CARGO, Site Constitutif, CHU Toulouse, Toulouse, France
| | - Julie Plaisancié
- Service de Génétique Médicale, Hôpital Purpan, CHU Toulouse, Toulouse, France. .,INSERM U1056, UDEAR, Equipe 4, Université Toulouse III, Toulouse, France. .,Centre de Référence des Affections Rares en Génétique Ophtalmologique CARGO, Site Constitutif, CHU Toulouse, Toulouse, France.
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31
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Martens C, Politis A. A glimpse into the molecular mechanism of integral membrane proteins through hydrogen-deuterium exchange mass spectrometry. Protein Sci 2020; 29:1285-1301. [PMID: 32170968 PMCID: PMC7255514 DOI: 10.1002/pro.3853] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/11/2020] [Accepted: 03/11/2020] [Indexed: 01/07/2023]
Abstract
Integral membrane proteins (IMPs) control countless fundamental biological processes and constitute the majority of drug targets. For this reason, uncovering their molecular mechanism of action has long been an intense field of research. They are, however, notoriously difficult to work with, mainly due to their localization within the heterogeneous of environment of the biological membrane and the instability once extracted from the lipid bilayer. High‐resolution structures have unveiled many mechanistic aspects of IMPs but also revealed that the elucidation of static pictures has limitations. Hydrogen–deuterium exchange coupled to mass spectrometry (HDX‐MS) has recently emerged as a powerful biophysical tool for interrogating the conformational dynamics of proteins and their interactions with ligands. Its versatility has proven particularly useful to reveal mechanistic aspects of challenging classes of proteins such as IMPs. This review recapitulates the accomplishments of HDX‐MS as it has matured into an essential tool for membrane protein structural biologists.
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Affiliation(s)
- Chloe Martens
- Laboratory for the Structure and Function of Biological Membranes, Center for Structural Biology and Bioinformatics, Université Libre de Bruxelles, Brussels, Belgium
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32
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Park SH, Lee JH. Dynamic G Protein-Coupled Receptor Signaling Probed by Solution NMR Spectroscopy. Biochemistry 2020; 59:1065-1080. [PMID: 32092261 DOI: 10.1021/acs.biochem.0c00032] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for investigating various dynamic features of G protein-coupled receptor (GPCR) signaling. In this Perspective, we focus on NMR techniques to characterize ligand-dependent conformational dynamics of GPCRs as well as the interaction of GPCRs with their environment and ligands. We also describe circumstances under which each technique should be applied, their advantages and disadvantages, and how they can be combined with other strategies to deepen the understanding of GPCR signaling at the molecular level.
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Affiliation(s)
- Sho Hee Park
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Jung Ho Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
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33
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Kozielewicz P, Turku A, Schulte G. Molecular Pharmacology of Class F Receptor Activation. Mol Pharmacol 2020; 97:62-71. [PMID: 31591260 DOI: 10.1124/mol.119.117986] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 09/25/2019] [Indexed: 12/29/2022] Open
Abstract
The class Frizzled (FZD) or class F of G protein-coupled receptors consists of 10 FZD paralogues and Smoothened (SMO). FZDs coordinate wingless/Int-1 signaling and SMO mediates Hedgehog signaling. Class F receptor signaling is intrinsically important for embryonic development and its dysregulation leads to diseases, including diverse forms of tumors. With regard to the importance of class F signaling in human disease, these receptors provide an attractive target for therapeutics, exemplified by the use of SMO antagonists for the treatment of basal cell carcinoma. Here, we review recent structural insights in combination with a more detailed functional understanding of class F receptor activation, G protein coupling, conformation-based functional selectivity, and mechanistic details of activating cancer mutations, which will lay the basis for further development of class F-targeting small molecules for human therapy. SIGNIFICANCE STATEMENT: Stimulated by recent insights into the activation mechanisms of class F receptors from structural and functional analysis of Frizzled and Smoothened, we aim to summarize what we know about the molecular details of ligand binding, agonist-driven conformational changes, and class F receptor activation. A better understanding of receptor activation mechanisms will allow us to engage in structure- and mechanism-driven drug discovery with the potential to develop more isoform-selective and potentially pathway-selective drugs for human therapy.
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Affiliation(s)
- Pawel Kozielewicz
- Section of Receptor Biology and Signaling, Department Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Ainoleena Turku
- Section of Receptor Biology and Signaling, Department Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Gunnar Schulte
- Section of Receptor Biology and Signaling, Department Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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34
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Kozielewicz P, Turku A, Bowin CF, Petersen J, Valnohova J, Cañizal MCA, Ono Y, Inoue A, Hoffmann C, Schulte G. Structural insight into small molecule action on Frizzleds. Nat Commun 2020; 11:414. [PMID: 31964872 PMCID: PMC6972889 DOI: 10.1038/s41467-019-14149-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 12/09/2019] [Indexed: 01/05/2023] Open
Abstract
WNT-Frizzled (FZD) signaling plays a critical role in embryonic development, stem cell regulation and tissue homeostasis. FZDs are linked to severe human pathology and are seen as a promising target for therapy. Despite intense efforts, no small molecule drugs with distinct efficacy have emerged. Here, we identify the Smoothened agonist SAG1.3 as a partial agonist of FZD6 with limited subtype selectivity. Employing extensive in silico analysis, resonance energy transfer- and luciferase-based assays we describe the mode of action of SAG1.3. We define the ability of SAG1.3 to bind to FZD6 and to induce conformational changes in the receptor, recruitment and activation of G proteins and dynamics in FZD–Dishevelled interaction. Our results provide the proof-of-principle that FZDs are targetable by small molecules acting on their seven transmembrane spanning core. Thus, we provide a starting point for a structure-guided and mechanism-based drug discovery process to exploit the potential of FZDs as therapeutic targets. WNT-Frizzled (FZD) signaling plays a critical role in embryonic development, tissue homeostasis and human disease but no small molecule drugs targeting FZD with distinct efficacy have emerged so far. Here, authors identify the Smoothened agonist SAG1.3 as a partial agonist for FZD6 with limited subtype selectivity.
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Affiliation(s)
- Paweł Kozielewicz
- Section of Receptor Biology & Signaling, Department of Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
| | - Ainoleena Turku
- Section of Receptor Biology & Signaling, Department of Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
| | - Carl-Fredrik Bowin
- Section of Receptor Biology & Signaling, Department of Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
| | - Julian Petersen
- Section of Receptor Biology & Signaling, Department of Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
| | - Jana Valnohova
- Section of Receptor Biology & Signaling, Department of Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden
| | - Maria Consuelo Alonso Cañizal
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, 97078, Würzburg, Germany.,Institute for Molecular Cell Biology, CMB-Center for Molecular Biomedicine, University Hospital Jena, Friedrich-Schiller University Jena, Hans-Knöll-Strasse 2, 07745, Jena, Germany
| | - Yuki Ono
- Department of Pharmacological Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Asuka Inoue
- Department of Pharmacological Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Carsten Hoffmann
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, 97078, Würzburg, Germany.,Institute for Molecular Cell Biology, CMB-Center for Molecular Biomedicine, University Hospital Jena, Friedrich-Schiller University Jena, Hans-Knöll-Strasse 2, 07745, Jena, Germany
| | - Gunnar Schulte
- Section of Receptor Biology & Signaling, Department of Physiology & Pharmacology, Karolinska Institutet, S-17165, Stockholm, Sweden.
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35
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Milhem RM, Ali BR. Disorders of FZ-CRD; insights towards FZ-CRD folding and therapeutic landscape. Mol Med 2019; 26:4. [PMID: 31892318 PMCID: PMC6938638 DOI: 10.1186/s10020-019-0129-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 12/13/2019] [Indexed: 02/08/2023] Open
Abstract
The ER is hub for protein folding. Proteins that harbor a Frizzled cysteine-rich domain (FZ-CRD) possess 10 conserved cysteine motifs held by a unique disulfide bridge pattern which attains a correct fold in the ER. Little is known about implications of disease-causing missense mutations within FZ-CRD families. Mutations in FZ-CRD of Frizzled class receptor 4 (FZD4) and Muscle, skeletal, receptor tyrosine kinase (MuSK) and Receptor tyrosine kinase-like orphan receptor 2 (ROR2) cause Familial Exudative Vitreoretinopathy (FEVR), Congenital Myasthenic Syndrome (CMS), and Robinow Syndrome (RS) respectively. We highlight reported pathogenic inherited missense mutations in FZ-CRD of FZD4, MuSK and ROR2 which misfold, and traffic abnormally in the ER, with ER-associated degradation (ERAD) as a common pathogenic mechanism for disease. Our review shows that all studied FZ-CRD mutants of RS, FEVR and CMS result in misfolded proteins and/or partially misfolded proteins with an ERAD fate, thus we coin them as "disorders of FZ-CRD". Abnormal trafficking was demonstrated in 17 of 29 mutants studied; 16 mutants were within and/or surrounding the FZ-CRD with two mutants distant from FZ-CRD. These ER-retained mutants were improperly N-glycosylated confirming ER-localization. FZD4 and MuSK mutants were tagged with polyubiquitin chains confirming targeting for proteasomal degradation. Investigating the cellular and molecular mechanisms of these mutations is important since misfolded protein and ER-targeted therapies are in development. The P344R-MuSK kinase mutant showed around 50% of its in-vitro autophosphorylation activity and P344R-MuSK increased two-fold on proteasome inhibition. M105T-FZD4, C204Y-FZD4, and P344R-MuSK mutants are thermosensitive and therefore, might benefit from extending the investigation to a larger number of chemical chaperones and/or proteasome inhibitors. Nonetheless, FZ-CRD ER-lipidation it less characterized in the literature and recent structural data sheds light on the importance of lipidation in protein glycosylation, proper folding, and ER trafficking. Current treatment strategies in-place for the conformational disease landscape is highlighted. From this review, we envision that disorders of FZ-CRD might be receptive to therapies that target FZ-CRD misfolding, regulation of fatty acids, and/or ER therapies; thus paving the way for a newly explored paradigm to treat different diseases with common defects.
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Affiliation(s)
- Reham M. Milhem
- Department of Natural and Applied Sciences, University of Dubai, P.O.Box: 14143, Academic City, Dubai, United Arab Emirates
| | - Bassam R. Ali
- Department of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, Abu Dhabi, United Arab Emirates
- Zayed Center for Health Sciences, United Arab Emirates University, Al-Ain, Abu Dhabi, United Arab Emirates
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36
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Sugar-mediated regulation of a c-di-GMP phosphodiesterase in Vibrio cholerae. Nat Commun 2019; 10:5358. [PMID: 31767877 PMCID: PMC6877527 DOI: 10.1038/s41467-019-13353-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 10/31/2019] [Indexed: 01/03/2023] Open
Abstract
Biofilm formation protects bacteria from stresses including antibiotics and host immune responses. Carbon sources can modulate biofilm formation and host colonization in Vibrio cholerae, but the underlying mechanisms remain unclear. Here, we show that EIIAGlc, a component of the phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS), regulates the intracellular concentration of the cyclic dinucleotide c-di-GMP, and thus biofilm formation. The availability of preferred sugars such as glucose affects EIIAGlc phosphorylation state, which in turn modulates the interaction of EIIAGlc with a c-di-GMP phosphodiesterase (hereafter referred to as PdeS). In a Drosophila model of V. cholerae infection, sugars in the host diet regulate gut colonization in a manner dependent on the PdeS-EIIAGlc interaction. Our results shed light into the mechanisms by which some nutrients regulate biofilm formation and host colonization.
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37
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Familial Exudative Vitreoretinopathy-Related Disease-Causing Genes and Norrin/ β-Catenin Signal Pathway: Structure, Function, and Mutation Spectrums. J Ophthalmol 2019; 2019:5782536. [PMID: 31827910 PMCID: PMC6885210 DOI: 10.1155/2019/5782536] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 09/07/2019] [Accepted: 09/26/2019] [Indexed: 02/06/2023] Open
Abstract
Familial exudative vitreoretinopathy (FEVR) is a hereditary ocular disorder characterized by incomplete vascularization/abnormality of peripheral retina. Four of the identified disease-causing genes of FEVR were NDP, FZD4, LRP5, and TSPAN12, the protein coded by which were the components of the Norrin/β-catenin signal pathway. In this review, we summarized and discussed the spectrum of mutations involving these four genes. By the end of 2017, the number of FEVR causing mutations reported for NDP, FZD4, LRP5, and TSPAN12 was, respectively, 26, 121, 58, and 40. Three most frequently reported mutations were c. 362G > A (p.R121Q) of NDP, c. 313A > G (p.M105V), and c.1282_1285delGACA (p.D428SfsX2) of FZD4. Mutations have a tendency to cluster in some “hotspots” domains which may be responsible for protein interactions.
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38
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Cho C, Wang Y, Smallwood PM, Williams J, Nathans J. Molecular determinants in Frizzled, Reck, and Wnt7a for ligand-specific signaling in neurovascular development. eLife 2019; 8:47300. [PMID: 31225798 PMCID: PMC6588345 DOI: 10.7554/elife.47300] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/07/2019] [Indexed: 12/28/2022] Open
Abstract
The molecular basis of Wnt-Frizzled specificity is a central question in developmental biology. Reck, a multi-domain and multi-functional glycosylphosphatidylinositol-anchored protein, specifically enhances beta-catenin signaling by Wnt7a and Wnt7b in cooperation with the 7-transmembrane protein Gpr124. Among amino acids that distinguish Wnt7a and Wnt7b from other Wnts, two clusters are essential for signaling in a Reck- and Gpr124-dependent manner. Both clusters are far from the site of Frizzled binding: one resides at the amino terminus and the second resides in a protruding loop. Within Reck, the fourth of five tandem repeats of an unusual domain with six-cysteines (the CC domain) is essential for Wnt7a stimulation: substitutions P256A and W261A in CC4 eliminate this activity without changing protein abundance or surface localization. Mouse embryos carrying ReckP256A,W261A have severe defects in forebrain angiogenesis, providing the strongest evidence to date that Reck promotes CNS angiogenesis by specifically stimulating Wnt7a and Wnt7b signaling.
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Affiliation(s)
- Chris Cho
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Yanshu Wang
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Philip M Smallwood
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - John Williams
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States
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39
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Schulte G, Kozielewicz P. Structural insight into Class F receptors - What have we learnt regarding agonist-induced activation? Basic Clin Pharmacol Toxicol 2019; 126 Suppl 6:17-24. [PMID: 30925000 DOI: 10.1111/bcpt.13235] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 03/19/2019] [Indexed: 12/11/2022]
Abstract
Class F receptors, including the ten Frizzleds (FZD1-10 ) and SMO, mediate the effects of WNTs and hedgehog proteins and belong to the superfamily of G protein-coupled receptors (GPCRs). While the recent, high-resolution insight into mechanisms of GPCR activation provides a better understanding of receptor activation in Class A, B and C GPCRs, it remains unclear how Class F receptors bind their ligands, how ligand binding is translated to receptor activation and how signal initiation and specification are achieved. Here, we summarize recent efforts in elucidating Class F receptor structure and activation mechanisms and critically discuss the progress made in this area. A better understanding of the activation mechanisms of Class F receptors is required to engage in mechanism-based and structure-guided drug discovery to exploit the large therapeutic potential of targeting these receptors pharmacologically.
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Affiliation(s)
- Gunnar Schulte
- Section of Receptor Biology & Signaling, Department Physiology & Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Paweł Kozielewicz
- Section of Receptor Biology & Signaling, Department Physiology & Pharmacology, Karolinska Institutet, Stockholm, Sweden
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40
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Norrin maintains malignancy of gastric cancer cells in part through activating AKT signaling. Biochem Biophys Res Commun 2019; 512:405-411. [DOI: 10.1016/j.bbrc.2019.03.044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 03/07/2019] [Indexed: 01/09/2023]
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41
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Valnohova J, Kowalski-Jahn M, Sunahara RK, Schulte G. Functional dissection of the N-terminal extracellular domains of Frizzled 6 reveals their roles for receptor localization and Dishevelled recruitment. J Biol Chem 2018; 293:17875-17887. [PMID: 30237173 PMCID: PMC6240854 DOI: 10.1074/jbc.ra118.004763] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/18/2018] [Indexed: 11/06/2022] Open
Abstract
The Frizzled (FZD) proteins belong to class F of G protein-coupled receptors (GPCRs) and are essential for various pathways involving the secreted lipoglycoproteins of the wingless/int-1 (WNT) family. A WNT-binding cysteine-rich domain (CRD) in FZDs is N-terminally located and connected to the seven transmembrane domain-spanning receptor core by a linker domain that has a variable length in different FZD homologs. However, the function and importance of this linker domain are poorly understood. Here we used systematic mutagenesis of FZD6 to define the minimal N-terminal domain sufficient for receptor surface expression and recruitment of the intracellular scaffold protein Dishevelled (DVL). Further, we identified a triad of evolutionarily conserved cysteines in the FZD linker domain that is crucial for receptor membrane expression and recruitment of DVL. Our results are in agreement with the concept that the conserved cysteines in the linker domain of FZDs assist with the formation of a common secondary structure in this region. We propose that this structure could be involved in agonist binding and receptor activation mechanisms that are similar to the binding and activation mechanisms known for other GPCRs.
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Affiliation(s)
- Jana Valnohova
- From the Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Maria Kowalski-Jahn
- From the Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Roger K Sunahara
- Department of Pharmacology, University of California San Diego School of Medicine, La Jolla, California 92093
| | - Gunnar Schulte
- From the Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, 171 65 Stockholm, Sweden.
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