1
|
Xu X, Wu G. Non-canonical Golgi-compartmentalized Gβγ signaling: mechanisms, functions, and therapeutic targets. Trends Pharmacol Sci 2023; 44:98-111. [PMID: 36494204 PMCID: PMC9901158 DOI: 10.1016/j.tips.2022.11.003] [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: 10/24/2022] [Revised: 11/14/2022] [Accepted: 11/15/2022] [Indexed: 12/13/2022]
Abstract
G protein Gβγ subunits are key mediators of G protein-coupled receptor (GPCR) signaling under physiological and pathological conditions; their inhibitors have been tested for the treatment of human disease. Conventional wisdom is that the Gβγ complex is activated and subsequently exerts its functions at the plasma membrane (PM). Recent studies have revealed non-canonical activation of Gβγ at intracellular organelles, where the Golgi apparatus is a major locale, via translocation or local activation. Golgi-localized Gβγ activates specific signaling cascades and regulates fundamental cell processes such as membrane trafficking, proliferation, and migration. More recent studies have shown that inhibiting Golgi-compartmentalized Gβγ signaling attenuates cardiomyocyte hypertrophy and prostate tumorigenesis, indicating new therapeutic targets. We review novel activation mechanisms and non-canonical functions of Gβγ at the Golgi, and discuss potential therapeutic interventions by targeting Golgi-biased Gβγ-directed signaling.
Collapse
Affiliation(s)
- Xin Xu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Guangyu Wu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA.
| |
Collapse
|
2
|
Anderson RC, Hanyroup S, Song YB, Mohamed-Moosa Z, van den Bout I, Schwulst AC, Kaiser UB, Millar RP, Newton CL. Functional Rescue of Inactivating Mutations of the Human Neurokinin 3 Receptor Using Pharmacological Chaperones. Int J Mol Sci 2022; 23:ijms23094587. [PMID: 35562976 PMCID: PMC9100388 DOI: 10.3390/ijms23094587] [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: 03/23/2022] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 12/04/2022] Open
Abstract
G protein-coupled receptors (GPCRs) facilitate the majority of signal transductions across cell membranes in humans, with numerous diseases attributed to inactivating GPCR mutations. Many of these mutations result in misfolding during nascent receptor synthesis in the endoplasmic reticulum (ER), resulting in intracellular retention and degradation. Pharmacological chaperones (PCs) are cell-permeant small molecules that can interact with misfolded receptors in the ER and stabilise/rescue their folding to promote ER exit and trafficking to the cell membrane. The neurokinin 3 receptor (NK3R) plays a pivotal role in the hypothalamic–pituitary–gonadal reproductive axis. We sought to determine whether NK3R missense mutations result in a loss of cell surface receptor expression and, if so, whether a cell-permeant small molecule NK3R antagonist could be repurposed as a PC to restore function to these mutants. Quantitation of cell surface expression levels of seven mutant NK3Rs identified in hypogonadal patients indicated that five had severely impaired cell surface expression. A small molecule NK3R antagonist, M8, increased cell surface expression in four of these five and resulted in post-translational receptor processing in a manner analogous to the wild type. Importantly, there was a significant improvement in receptor activation in response to neurokinin B (NKB) for all four receptors following their rescue with M8. This demonstrates that M8 may have potential for therapeutic development in the treatment of hypogonadal patients harbouring NK3R mutations. The repurposing of existing small molecule GPCR modulators as PCs represents a novel and therapeutically viable option for the treatment of disorders attributed to mutations in GPCRs that cause intracellular retention.
Collapse
Affiliation(s)
- Ross C. Anderson
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
- Correspondence:
| | - Sharika Hanyroup
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
| | - Yong Bhum Song
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Y.B.S.); (U.B.K.)
- Division of Research Center, Scripps Korea Antibody Institute, Chuncheon 24341, Korea
| | - Zulfiah Mohamed-Moosa
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
- Department of Anatomy and Physiology, Faculty of Veterinary Sciences, University of Pretoria, Private Bag X04, Pretoria 0110, South Africa
| | - Iman van den Bout
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
| | - Alexis C. Schwulst
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
| | - Ursula B. Kaiser
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Y.B.S.); (U.B.K.)
| | - Robert P. Millar
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
- Department of Integrative Biomedical Sciences, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Observatory 7925, South Africa
- Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh EH8 9JZ, UK
- School of Medicine, Medical and Biological Sciences Building, University of St Andrews, St Andrews KY16 9TF, UK
| | - Claire L. Newton
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
- Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh EH8 9JZ, UK
| |
Collapse
|
3
|
Ulloa-Aguirre A, Zariñán T, Gutiérrez-Sagal R, Tao YX. Targeting trafficking as a therapeutic avenue for misfolded GPCRs leading to endocrine diseases. Front Endocrinol (Lausanne) 2022; 13:934685. [PMID: 36093106 PMCID: PMC9452723 DOI: 10.3389/fendo.2022.934685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 07/13/2022] [Indexed: 02/05/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are plasma membrane proteins associated with an array of functions. Mutations in these receptors lead to a number of genetic diseases, including diseases involving the endocrine system. A particular subset of loss-of-function mutant GPCRs are misfolded receptors unable to traffic to their site of function (i.e. the cell surface plasma membrane). Endocrine disorders in humans caused by GPCR misfolding include, among others, hypo- and hyper-gonadotropic hypogonadism, morbid obesity, familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism, X-linked nephrogenic diabetes insipidus, congenital hypothyroidism, and familial glucocorticoid resistance. Several in vitro and in vivo experimental approaches have been employed to restore function of some misfolded GPCRs linked to endocrine disfunction. The most promising approach is by employing pharmacological chaperones or pharmacoperones, which assist abnormally and incompletely folded proteins to refold correctly and adopt a more stable configuration to pass the scrutiny of the cell's quality control system, thereby correcting misrouting. This review covers the most important aspects that regulate folding and traffic of newly synthesized proteins, as well as the experimental approaches targeted to overcome protein misfolding, with special focus on GPCRs involved in endocrine diseases.
Collapse
Affiliation(s)
- Alfredo Ulloa-Aguirre
- Red de Apoyo a la Investigación (RAI), National University of Mexico and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City, Mexico
- *Correspondence: Alfredo Ulloa-Aguirre,
| | - Teresa Zariñán
- Red de Apoyo a la Investigación (RAI), National University of Mexico and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City, Mexico
| | - Rubén Gutiérrez-Sagal
- Red de Apoyo a la Investigación (RAI), National University of Mexico and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City, Mexico
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology & Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, United States
| |
Collapse
|
4
|
Rivero-Müller A, Huhtaniemi I. Genetic variants of gonadotrophins and their receptors: Impact on the diagnosis and management of the infertile patient. Best Pract Res Clin Endocrinol Metab 2022; 36:101596. [PMID: 34802912 DOI: 10.1016/j.beem.2021.101596] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This narrative review is concerned with genetic variants of the genes encoding gonadotrophin subunits and their receptors, as well as their implications into the diagnosis and treatment of infertility. We first review briefly the basics of molecular biology and biochemistry of gonadotrophin and gonadotrophin receptor structure and function, then describe the phenotypic effects of polymorphisms and mutations of these genes, followed by diagnostic aspects. We will then summarise the information that inactivating gonadotrophin receptor mutations have provided about the controversial topic of extragonadal gonadotrophin action. Finally, we will close with the current and future therapeutic approaches on patients with gonadotrophin and their receptor mutations.
Collapse
Affiliation(s)
- Adolfo Rivero-Müller
- Department of Biochemistry and Molecular Biology, Medical University of Lublin, Lublin, 20-093, Poland
| | - Ilpo Huhtaniemi
- Institute of Reproductive and Developmental Biology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, W12 0NN, UK.
| |
Collapse
|
5
|
Ulloa-Aguirre A, Zariñán T, Jardón-Valadez E. Misfolded G Protein-Coupled Receptors and Endocrine Disease. Molecular Mechanisms and Therapeutic Prospects. Int J Mol Sci 2021; 22:ijms222212329. [PMID: 34830210 PMCID: PMC8622668 DOI: 10.3390/ijms222212329] [Citation(s) in RCA: 3] [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: 08/19/2021] [Revised: 09/28/2021] [Accepted: 10/01/2021] [Indexed: 11/30/2022] Open
Abstract
Misfolding of G protein-coupled receptors (GPCRs) caused by mutations frequently leads to disease due to intracellular trapping of the conformationally abnormal receptor. Several endocrine diseases due to inactivating mutations in GPCRs have been described, including X-linked nephrogenic diabetes insipidus, thyroid disorders, familial hypocalciuric hypercalcemia, obesity, familial glucocorticoid deficiency [melanocortin-2 receptor, MC2R (also known as adrenocorticotropin receptor, ACTHR), and reproductive disorders. In these mutant receptors, misfolding leads to endoplasmic reticulum retention, increased intracellular degradation, and deficient trafficking of the abnormal receptor to the cell surface plasma membrane, causing inability of the receptor to interact with agonists and trigger intracellular signaling. In this review, we discuss the mechanisms whereby mutations in GPCRs involved in endocrine function in humans lead to misfolding, decreased plasma membrane expression of the receptor protein, and loss-of-function diseases, and also describe several experimental approaches employed to rescue trafficking and function of the misfolded receptors. Special attention is given to misfolded GPCRs that regulate reproductive function, given the key role played by these particular membrane receptors in sexual development and fertility, and recent reports on promising therapeutic interventions targeting trafficking of these defective proteins to rescue completely or partially their normal function.
Collapse
Affiliation(s)
- Alfredo Ulloa-Aguirre
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City 14080, Mexico;
- Correspondence:
| | - Teresa Zariñán
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City 14080, Mexico;
| | - Eduardo Jardón-Valadez
- Departamento de Recursos de la Tierra, Universidad Autónoma Metropolitana-Lerma, Lerma de Villada 52005, Estado de México, Mexico;
| |
Collapse
|