Direct evidence that the GPCR CysLTR2 mutant causative of uveal melanoma is constitutively active with highly biased signaling
| Autor: | Jordan M. Mattheisen, Amanda R. Moore, Yu Chen, Ping Chi, Manija A. Kazmi, Tyler D. Hitchman, Mizuho Horioka, Thomas P. Sakmar, Emilie Ceraudo, Thomas Huber |
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| Rok vydání: | 2021 |
| Předmět: |
Uveal Neoplasms
0301 basic medicine Receptors Vasopressin Glutamine MV missense variant Mutant HTRF homogeneous time-resolved fluorescence immunoassay UVM uveal melanoma Biochemistry Malignant transformation CysLTR2 Receptor Melanoma β-arrestins biased signaling CA constitutive activity BRET bioluminescent resonance energy transfer LTD4 leukotriene D4 beta-Arrestin 2 CAM constitutively active mutant Cell biology Gene Expression Regulation Neoplastic EPAC exchange protein activated by cAMP LiCl lithium chloride uveal melanoma Signal transduction signaling Protein Binding Signal Transduction Research Article PLCβ phospholipase C-β Recombinant Fusion Proteins Green Fluorescent Proteins V2(A)6 hexa-alanine variant Biology Models Biological RLuc3 Renilla Luciferase DPBS Dulbecco’s PBS 03 medical and health sciences FBS fetal bovine serum Downregulation and upregulation Arrestin Humans BRET2 bioluminescent resonance energy transfer 2 constitutive activity Molecular Biology G protein-coupled receptor Receptors Leukotriene CysLTR2 cysteinyl-leukotriene receptor 2 030102 biochemistry & molecular biology Lysine G protein Cell Biology CI confidence interval Kinetics HEK293 Cells 030104 developmental biology Cysteinyl leukotriene receptor 2 Amino Acid Substitution G protein–coupled receptor Mutation GTP-Binding Protein alpha Subunits Gq-G11 GPCR G protein–coupled receptor IP1 d-myo-inositol-1-phosphate BSA bovine serum albumin |
| Zdroj: | The Journal of Biological Chemistry |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.ra120.015352 |
| Popis: | Uveal melanoma is the most common eye cancer in adults and is clinically and genetically distinct from skin cutaneous melanoma. In a subset of cases, the oncogenic driver is an activating mutation in CYSLTR2, the gene encoding the G protein–coupled receptor cysteinyl-leukotriene receptor 2 (CysLTR2). The mutant CYSLTR2 encodes for the CysLTR2–L129Q receptor, with the substitution of Leu to Gln at position 129 (3.43). The ability of CysLTR2–L129Q to cause malignant transformation has been hypothesized to result from constitutive activity, but how the receptor could escape desensitization is unknown. Here, we characterize the functional properties of CysLTR2–L129Q. We show that CysLTR2–L129Q is a constitutively active mutant that strongly drives Gq/11 signaling pathways. However, CysLTR2–L129Q only poorly recruits β-arrestin. Using a modified Slack–Hall operational model, we quantified the constitutive activity for both pathways and conclude that CysLTR2–L129Q displays profound signaling bias for Gq/11 signaling pathways while escaping β-arrestin–mediated downregulation. CYSLTR2 is the first known example of a G protein–coupled receptor driver oncogene that encodes a highly biased constitutively active mutant receptor. These results provide new insights into the mechanism of CysLTR2–L129Q oncoprotein signaling and suggest CYSLTR2 as a promising potential therapeutic target in uveal melanoma. |
| Databáze: | OpenAIRE |
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