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Zhang Y, Yu Z, Sun M, Du R, Gao H, Dai Q, Dong Y, Liu C, Yin M, Xu T, Zhang X, Liu J, Xu J. Redox-modulated SNX25 as a novel regulator of GPCR-G protein signaling from endosomes. Redox Biol 2024; 75:103253. [PMID: 38936254 PMCID: PMC11259961 DOI: 10.1016/j.redox.2024.103253] [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: 05/24/2024] [Accepted: 06/20/2024] [Indexed: 06/29/2024] Open
Abstract
GPCR-G protein signaling from endosomes plays a crucial role in various physiological and pathological processes. However, the mechanism by which endosomal G protein signaling is terminated remains largely unknown. In this study, we aimed to investigate the regulatory mechanisms involved in terminating the signaling of Gα subunits from endosomes. Through structural analysis and cell-based assays, we have discovered that SNX25, a protein that targets endosomes via its PXA or PXC domain, interacts with regulator of G protein signaling (RGS) proteins (including RGS2, RGS4, RGS8, and RGS17) in a redox-regulated manner. The interaction between SNX25 and these RGS proteins enhances their GTPase-accelerating activity towards Gαi/q and their ability to bind GDP-bound (inactive form) Gαi/q. As a result, SNX25 recruits these RGS proteins to endosomes, leading to the termination of endosomal Gαi/q signaling. Furthermore, we have found that the SNX25/RGS complex also exerts a negative regulatory effect on Gαi/q signaling from the plasma membrane. This is achieved by recruiting Gαi/q to endosomes and preventing its activation on the plasma membrane. Our findings shed light on the previously unknown role of redox-modulated SNX25 in inhibiting Gαi/q signaling, thereby uncovering a novel mechanism for terminating Gαi/q signaling from endosomes. Importantly, this study expands our understanding of the regulation of GPCR-Gαi/q signaling beyond the plasma membrane.
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Affiliation(s)
- Yulong Zhang
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhijun Yu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Mingwei Sun
- Basic Research Center, Bioland Laboratory, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, 510530, China
| | - Ruyue Du
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hanhan Gao
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qiankun Dai
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yan Dong
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; China-New Zealand Joint Laboratory on Biomedicine and Health, Guangzhou, 510530, China
| | - Cuicui Liu
- Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Menghui Yin
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Tingting Xu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; China-New Zealand Joint Laboratory on Biomedicine and Health, Guangzhou, 510530, China
| | - Xiaofei Zhang
- Basic Research Center, Bioland Laboratory, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, 510530, China; CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Center for Cell Lineage and Development, GIBH-HKU Guangdong-Hong Kong Stem Cell and Regenerative Medicine Research Centre, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, 510530, China
| | - Jinsong Liu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; China-New Zealand Joint Laboratory on Biomedicine and Health, Guangzhou, 510530, China.
| | - Jinxin Xu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China; China-New Zealand Joint Laboratory on Biomedicine and Health, Guangzhou, 510530, China.
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Majerciak V, Alvarado-Hernandez B, Ma Y, Duduskar S, Lobanov A, Cam M, Zheng ZM. KSHV promotes oncogenic FOS to inhibit nuclease AEN and transactivate RGS2 for AKT phosphorylation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.27.577582. [PMID: 38410462 PMCID: PMC10896338 DOI: 10.1101/2024.01.27.577582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) ORF57 is a lytic RNA-binding protein. We applied BCBL-1 cells in lytic KSHV infection and performed UV cross-linking immunoprecipitation (CLIP) followed by RNA-seq of the CLIPed RNA fragments (CLIP-seq). We identified ORF57-bound transcripts from 544 host protein-coding genes. By comparing with the RNA-seq profiles from BCBL-1 cells with latent and lytic KSHV infection and from HEK293T cells with and without ORF57 expression, we identified FOS and CITED2 RNAs being two common ORF57-specific RNA targets. FOS dimerizes with JUN as a transcription factor AP-1 involved in cell proliferation, differentiation, and transformation. Knockout of the ORF57 gene from the KSHV genome led BAC16-iSLK cells incapable of FOS expression in KSHV lytic infection. The dysfunctional KSHV genome in FOS expression could be rescued by Lenti-ORF57 virus infection. ORF57 protein does not regulate FOS translation but binds to the 13-nt RNA motif near the FOS RNA 5' end and prolongs FOS mRNA half-life 7.7 times longer than it is in the absence of ORF57. This binding of ORF57 to FOS RNA is competitive to the binding of a host nuclease AEN (also referred to as ISG20L1). KSHV infection inhibits the expression of AEN, but not exosomal RNA helicase MTR4. FOS expression mediated by ORF57 inhibits AEN transcription, but transactivates RGS2, a regulator of G-protein coupled receptors. FOS binds a conserved AP-1 site in the RGS2 promoter and enhances RGS2 expression to phosphorylate AKT. Altogether, we have discovered that KSHV ORF57 specifically binds and stabilizes FOS RNA to increase FOS expression, thereby disturbing host gene expression and inducing pathogenesis during KSHV lytic infection.
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Affiliation(s)
- Vladimir Majerciak
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, MD, 21702, USA
| | - Beatriz Alvarado-Hernandez
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, MD, 21702, USA
| | - Yanping Ma
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, MD, 21702, USA
| | - Shivalee Duduskar
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, MD, 21702, USA
| | - Alexei Lobanov
- CCR Collaborative Bioinformatics Resource, Center for Cancer Research, NCI/NIH, Bethesda, MD, 20892, USA
| | - Maggie Cam
- CCR Collaborative Bioinformatics Resource, Center for Cancer Research, NCI/NIH, Bethesda, MD, 20892, USA
| | - Zhi-Ming Zheng
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, MD, 21702, USA
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3
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Sun B, Smith N, Dixon AJ, Osei-Owusu P. Phosphodiesterases Mediate the Augmentation of Myogenic Constriction by Inhibitory G Protein Signaling and is Negatively Modulated by the Dual Action of RGS2 and 5. FUNCTION 2024; 5:zqae003. [PMID: 38486977 PMCID: PMC10935470 DOI: 10.1093/function/zqae003] [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: 11/06/2023] [Revised: 01/09/2024] [Accepted: 01/16/2024] [Indexed: 03/17/2024] Open
Abstract
G protein regulation by regulators of G protein signaling (RGS) proteins play a key role in vascular tone maintenance. The loss of Gi/o and Gq/11 regulation by RGS2 and RGS5 in non-pregnant mice is implicated in augmented vascular tone and decreased uterine blood flow (UBF). RGS2 and 5 are closely related and co-expressed in uterine arteries (UA). However, whether and how RGS2 and 5 coordinate their regulatory activities to finetune G protein signaling and regulate vascular tone are unclear. Here, we determined how the integrated activity of RGS2 and 5 modulates vascular tone to promote UBF. Using ultrasonography and pressure myography, we examined uterine hemodynamics and myogenic tone (MT) of UA of wild type (WT), Rgs2-/-, Rgs5-/-, and Rgs2/5 dbKO mice. We found that MT was reduced in Rgs5-/- relative to WT or Rgs2-/- UA. Activating Gi/o with dopamine increased, whereas exogenous cAMP decreased MT in Rgs5-/- UA to levels in WT UA. Dual deletion of Rgs2 and 5 abolished the reduced MT due to the absence of Rgs5 and enhanced dopamine-induced Gi/o effects in Rgs2/5 dbKO UA. Conversely, and as in WT UA, Gi/o inhibition with pertussis toxin or exogenous cAMP decreased MT in Rgs2/5 dbKO to levels in Rgs5-/- UA. Inhibition of phosphodiesterases (PDE) concentration-dependently decreased and normalized MT in all genotypes, and blocked dopamine-induced MT augmentation in Rgs2-/-, Rgs5-/-, and Rgs2/5 dbKO UA. We conclude that Gi/o augments UA MT in the absence of RGS2 by a novel mechanism involving PDE-mediated inhibition of cAMP-dependent vasodilatation..
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Affiliation(s)
- Bo Sun
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Nia Smith
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Alethia J Dixon
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Patrick Osei-Owusu
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
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Semenikhina M, Lysikova DV, Spires DR, Domondon M, Stadler K, Palygin O, Ilatovskaya DV. Transcriptomic changes in glomeruli in response to a high salt challenge in the Dahl SS rat. Physiol Genomics 2024; 56:98-111. [PMID: 37955135 PMCID: PMC11281811 DOI: 10.1152/physiolgenomics.00075.2023] [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: 07/21/2023] [Revised: 10/31/2023] [Accepted: 11/04/2023] [Indexed: 11/14/2023] Open
Abstract
Salt sensitivity impacts a significant portion of the population and is an important contributor to the development of chronic kidney disease. One of the significant early predictors of salt-induced damage is albuminuria, which reflects the deterioration of the renal filtration barrier: the glomerulus. Despite significant research efforts, there is still a gap in knowledge regarding the molecular mechanisms and signaling networks contributing to instigating and/or perpetuating salt-induced glomerular injury. To address this gap, we used 8-wk-old male Dahl salt-sensitive rats fed a normal-salt diet (0.4% NaCl) or challenged with a high-salt diet (4% NaCl) for 3 wk. At the end of the protocol, a pure fraction of renal glomeruli obtained by differential sieving was used for next-generation RNA sequencing and comprehensive semi-automatic transcriptomic data analyses, which revealed 149 differentially expressed genes (107 and 42 genes were downregulated and upregulated, respectively). Furthermore, a combination of predictive gene correlation networks and computational bioinformatic analyses revealed pathways impacted by a high salt dietary challenge, including renal metabolism, mitochondrial function, apoptotic signaling and fibrosis, cell cycle, inflammatory and immune responses, circadian clock, cytoskeletal organization, G protein-coupled receptor signaling, and calcium transport. In conclusion, we report here novel transcriptomic interactions and corresponding predicted pathways affecting glomeruli under salt-induced stress.NEW & NOTEWORTHY Our study demonstrated novel pathways affecting glomeruli under stress induced by dietary salt. Predictive gene correlation networks and bioinformatic semi-automatic analysis revealed changes in the pathways relevant to mitochondrial function, inflammatory, apoptotic/fibrotic processes, and cell calcium transport.
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Affiliation(s)
- Marharyta Semenikhina
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Daria V Lysikova
- Department of Physiology, Augusta University, Augusta, Georgia, United States
| | - Denisha R Spires
- Department of Physiology, Augusta University, Augusta, Georgia, United States
| | - Mark Domondon
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Krisztian Stadler
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States
| | - Oleg Palygin
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Daria V Ilatovskaya
- Department of Physiology, Augusta University, Augusta, Georgia, United States
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5
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Sneha NP, Dharshini SAP, Taguchi YH, Gromiha MM. Investigating Neuron Degeneration in Huntington's Disease Using RNA-Seq Based Transcriptome Study. Genes (Basel) 2023; 14:1801. [PMID: 37761940 PMCID: PMC10530489 DOI: 10.3390/genes14091801] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 09/02/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Huntington's disease (HD) is a progressive neurodegenerative disorder caused due to a CAG repeat expansion in the huntingtin (HTT) gene. The primary symptoms of HD include motor dysfunction such as chorea, dystonia, and involuntary movements. The primary motor cortex (BA4) is the key brain region responsible for executing motor/movement activities. Investigating patient and control samples from the BA4 region will provide a deeper understanding of the genes responsible for neuron degeneration and help to identify potential markers. Previous studies have focused on overall differential gene expression and associated biological functions. In this study, we illustrate the relationship between variants and differentially expressed genes/transcripts. We identified variants and their associated genes along with the quantification of genes and transcripts. We also predicted the effect of variants on various regulatory activities and found that many variants are regulating gene expression. Variants affecting miRNA and its targets are also highlighted in our study. Co-expression network studies revealed the role of novel genes. Function interaction network analysis unveiled the importance of genes involved in vesicle-mediated transport. From this unified approach, we propose that genes expressed in immune cells are crucial for reducing neuron death in HD.
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Affiliation(s)
- Nela Pragathi Sneha
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India; (N.P.S.); (S.A.P.D.)
| | - S. Akila Parvathy Dharshini
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India; (N.P.S.); (S.A.P.D.)
| | - Y.-h. Taguchi
- Department of Physics, Chuo University, Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan;
| | - M. Michael Gromiha
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India; (N.P.S.); (S.A.P.D.)
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Sun Y, Li J, Wang L, Cong T, Zhai X, Li L, Wu H, Li S, Xiao Z. Identification of Potential Diagnoses Based on Immune Infiltration and Autophagy Characteristics in Major Depressive Disorder. Front Genet 2022; 13:702366. [PMID: 35559009 PMCID: PMC9087348 DOI: 10.3389/fgene.2022.702366] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 03/25/2022] [Indexed: 12/12/2022] Open
Abstract
Background: Major depressive disorder (MDD) is a serious mental illness characterized by mood changes and high suicide rates. However, no studies are available to support a blood test method for MDD diagnosis. The objective of this research was to identify potential peripheral blood biomarkers for MDD and characterize the novel pathophysiology. Methods: We accessed whole blood microarray sequencing data for MDD and control samples from public databases. Biological functions were analysed by GO and KEGG pathway enrichment analyses using the clusterprofile R package. Infiltrated immune cell (IIC) proportions were identified using the CIBERSORT algorithm. Clustering was performed using the ConsensusClusterPlus R package. Protein–protein interactions (PPI) were assessed by constructing a PPI network using STRING and visualized using Cytoscape software. Rats were exposed to chronic unpredictable mild stress (CUMS) for 6 weeks to induce stress behaviour. Stress behaviour was evaluated by open field experiments and forced swimming tests. Flow cytometry was used to analyse the proportion of CD8+ T cells. The expression of the corresponding key genes was detected by qRT–PCR. Results: We divided MDD patients into CD8H and CD8L clusters. The functional enrichment of marker genes in the CD8H cluster indicated that autophagy-related terms and pathways were significantly enriched. Furthermore, we obtained 110 autophagy-related marker genes (ARMGs) in the CD8H cluster through intersection analysis. GO and KEGG analyses further showed that these ARMGs may regulate a variety of autophagy processes and be involved in the onset and advancement of MDD. Finally, 10 key ARMGs were identified through PPI analysis: RAB1A, GNAI3, VAMP7, RAB33B, MYC, LAMP2, RAB11A, HIF1A, KIF5B, and PTEN. In the CUMS model, flow cytometric analysis confirmed the above findings. qRT–PCR revealed significant decreases in the mRNA levels of Gnai3, Rab33b, Lamp2, and Kif5b in the CUMS groups. Conclusion: In this study, MDD was divided into two subtypes. We combined immune infiltrating CD8+ T cells with autophagy-related genes and screened a total of 10 ARMG genes. In particular, RAB1A, GNAI3, RAB33B, LAMP2, and KIF5B were first reported in MDD. These genes may offer new hope for the clinical diagnosis of MDD.
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Affiliation(s)
- Ye Sun
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Jinying Li
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Lin Wang
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Ting Cong
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Xiuli Zhai
- Department of Anesthesiology, Inner Mongolia People's Hospital, Hohhot, China
| | - Liya Li
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Haikuo Wu
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Shouxin Li
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Zhaoyang Xiao
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
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Asli A, Higazy-Mreih S, Avital-Shacham M, Kosloff M. Residue-level determinants of RGS R4 subfamily GAP activity and specificity towards the G i subfamily. Cell Mol Life Sci 2021; 78:6305-6318. [PMID: 34292354 PMCID: PMC11072900 DOI: 10.1007/s00018-021-03898-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 06/18/2021] [Accepted: 07/09/2021] [Indexed: 01/01/2023]
Abstract
The structural basis for the GTPase-accelerating activity of regulators of G protein signaling (RGS) proteins, as well as the mechanistic basis for their specificity in interacting with the heterotrimeric (αβγ) G proteins they inactivate, is not sufficiently understood at the family level. Here, we used biochemical assays to compare RGS domains across the RGS family and map those individual residues that favorably contribute to GTPase-accelerating activity, and those residues responsible for attenuating RGS domain interactions with Gα subunits. We show that conserved interactions of RGS residues with both the Gα switch I and II regions are crucial for RGS activity, while the reciprocal effects of "modulatory" and "disruptor" residues selectively modulate RGS activity. Our results quantify how specific interactions between RGS domains and Gα subunits are set by a balance between favorable RGS residue interactions with particular Gα switch regions, and unfavorable interactions with the Gα helical domain.
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Affiliation(s)
- Ali Asli
- The Department of Human Biology, Faculty of Natural Science, University of Haifa, 199 Aba Khoushy Ave., Mt. Carmel, 3498838, Haifa, Israel
| | - Sabreen Higazy-Mreih
- The Department of Human Biology, Faculty of Natural Science, University of Haifa, 199 Aba Khoushy Ave., Mt. Carmel, 3498838, Haifa, Israel
| | - Meirav Avital-Shacham
- The Department of Human Biology, Faculty of Natural Science, University of Haifa, 199 Aba Khoushy Ave., Mt. Carmel, 3498838, Haifa, Israel
| | - Mickey Kosloff
- The Department of Human Biology, Faculty of Natural Science, University of Haifa, 199 Aba Khoushy Ave., Mt. Carmel, 3498838, Haifa, Israel.
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Chinn IK, Xie Z, Chan EC, Nagata BM, Koval A, Chen WS, Zhang F, Ganesan S, Hong DN, Suzuki M, Nardone G, Moore IN, Katanaev VL, Balazs AE, Liu C, Lupski JR, Orange JS, Druey KM. Short stature and combined immunodeficiency associated with mutations in RGS10. Sci Signal 2021; 14:14/693/eabc1940. [PMID: 34315806 DOI: 10.1126/scisignal.abc1940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report the clinical and molecular phenotype of three siblings from one family, who presented with short stature and immunodeficiency and carried uncharacterized variants in RGS10 (c.489_491del:p.E163del and c.G511T:p.A171S). This gene encodes regulator of G protein signaling 10 (RGS10), a member of a large family of GTPase-activating proteins (GAPs) that targets heterotrimeric G proteins to constrain the activity of G protein-coupled receptors, including receptors for chemoattractants. The affected individuals exhibited systemic abnormalities directly related to the RGS10 mutations, including recurrent infections, hypergammaglobulinemia, profoundly reduced lymphocyte chemotaxis, abnormal lymph node architecture, and short stature due to growth hormone deficiency. Although the GAP activity of each RGS10 variant was intact, each protein exhibited aberrant patterns of PKA-mediated phosphorylation and increased cytosolic and cell membrane localization and activity compared to the wild-type protein. We propose that the RGS10 p.E163del and p.A171S mutations lead to mislocalization of the RGS10 protein in the cytosol, thereby resulting in attenuated chemokine signaling. This study suggests that RGS10 is critical for both immune competence and normal hormonal metabolism in humans and that rare RGS10 variants may contribute to distinct systemic genetic disorders.
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Affiliation(s)
- Ivan K Chinn
- Department of Pediatrics, Texas Children's Hospital and Baylor College of Medicine, Houston, TX 77030, USA
| | - Zhihui Xie
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH Bethesda, MD 20892, USA
| | - Eunice C Chan
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH Bethesda, MD 20892, USA
| | - Bianca M Nagata
- Infectious Disease Pathogenesis Section, NIAID/NIH, Bethesda, MD 20892, USA
| | - Alexey Koval
- Department of Cell Physiology and Metabolism, Translational Research Centre in Oncohaematology, Faculty of Medicine, University of Geneva, Rue Michel-Servet 1, Geneva CH-1211, Switzerland.,School of Biomedicine, Far Eastern Federal University, 8 ul. Sukhanova, Vladivostok 690950, Russia
| | - Wei-Sheng Chen
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH Bethesda, MD 20892, USA
| | - Fan Zhang
- Transgenic Core, NHLBI/NIH, Bethesda, MD 20892 USA
| | - Sundar Ganesan
- Biological Imaging Section, NIAID/NIH Bethesda, MD 20892, USA
| | - Diana N Hong
- Department of Pediatrics, Texas Children's Hospital and Baylor College of Medicine, Houston, TX 77030, USA
| | - Motoshi Suzuki
- Protein Chemistry Section, NIAID/NIH, Bethesda, MD 20892, USA
| | - Glenn Nardone
- Protein Chemistry Section, NIAID/NIH, Bethesda, MD 20892, USA
| | - Ian N Moore
- Infectious Disease Pathogenesis Section, NIAID/NIH, Bethesda, MD 20892, USA
| | - Vladimir L Katanaev
- Department of Cell Physiology and Metabolism, Translational Research Centre in Oncohaematology, Faculty of Medicine, University of Geneva, Rue Michel-Servet 1, Geneva CH-1211, Switzerland.,School of Biomedicine, Far Eastern Federal University, 8 ul. Sukhanova, Vladivostok 690950, Russia
| | - Andrea E Balazs
- Department of Pediatrics, Texas Children's Hospital and Baylor College of Medicine, Houston, TX 77030, USA
| | - Chengyu Liu
- Transgenic Core, NHLBI/NIH, Bethesda, MD 20892 USA
| | - James R Lupski
- Department of Molecular and Human Genetics and Baylor-Hopkins Center for Mendelian Genomics, Baylor College of Medicine, Houston, TX 77030, USA.,Texas Children’s Hospital, Houston, TX 77030, USA
| | - Jordan S Orange
- Columbia University Vagelos College of Physicians and Surgeons and New York-Presbyterian Hospital
| | - Kirk M Druey
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH Bethesda, MD 20892, USA.
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9
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Nubbemeyer B, Pepanian A, Paul George AA, Imhof D. Strategies towards Targeting Gαi/s Proteins: Scanning of Protein-Protein Interaction Sites To Overcome Inaccessibility. ChemMedChem 2021; 16:1696-1715. [PMID: 33615736 PMCID: PMC8252600 DOI: 10.1002/cmdc.202100039] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Indexed: 12/16/2022]
Abstract
Heterotrimeric G proteins are classified into four subfamilies and play a key role in signal transduction. They transmit extracellular signals to intracellular effectors subsequent to the activation of G protein-coupled receptors (GPCRs), which are targeted by over 30 % of FDA-approved drugs. However, addressing G proteins as drug targets represents a compelling alternative, for example, when G proteins act independently of the corresponding GPCRs, or in cases of complex multifunctional diseases, when a large number of different GPCRs are involved. In contrast to Gαq, efforts to target Gαi/s by suitable chemical compounds has not been successful so far. Here, a comprehensive analysis was conducted examining the most important interface regions of Gαi/s with its upstream and downstream interaction partners. By assigning the existing compounds and the performed approaches to the respective interfaces, the druggability of the individual interfaces was ranked to provide perspectives for selective targeting of Gαi/s in the future.
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Affiliation(s)
- Britta Nubbemeyer
- Pharmaceutical Biochemistry and BioanalyticsPharmaceutical InstituteUniversity of BonnAn der Immenburg 453121BonnGermany
| | - Anna Pepanian
- Pharmaceutical Biochemistry and BioanalyticsPharmaceutical InstituteUniversity of BonnAn der Immenburg 453121BonnGermany
| | | | - Diana Imhof
- Pharmaceutical Biochemistry and BioanalyticsPharmaceutical InstituteUniversity of BonnAn der Immenburg 453121BonnGermany
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Polit A, Mystek P, Błasiak E. Every Detail Matters. That Is, How the Interaction between Gα Proteins and Membrane Affects Their Function. MEMBRANES 2021; 11:222. [PMID: 33804791 PMCID: PMC8003949 DOI: 10.3390/membranes11030222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 03/17/2021] [Accepted: 03/18/2021] [Indexed: 11/16/2022]
Abstract
In highly organized multicellular organisms such as humans, the functions of an individual cell are dependent on signal transduction through G protein-coupled receptors (GPCRs) and subsequently heterotrimeric G proteins. As most of the elements belonging to the signal transduction system are bound to lipid membranes, researchers are showing increasing interest in studying the accompanying protein-lipid interactions, which have been demonstrated to not only provide the environment but also regulate proper and efficient signal transduction. The mode of interaction between the cell membrane and G proteins is well known. Despite this, the recognition mechanisms at the molecular level and how the individual G protein-membrane attachment signals are interrelated in the process of the complex control of membrane targeting of G proteins remain unelucidated. This review focuses on the mechanisms by which mammalian Gα subunits of G proteins interact with lipids and the factors responsible for the specificity of membrane association. We summarize recent data on how these signaling proteins are precisely targeted to a specific site in the membrane region by introducing well-defined modifications as well as through the presence of polybasic regions within these proteins and interactions with other components of the heterocomplex.
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Affiliation(s)
- Agnieszka Polit
- Department of Physical Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland; (P.M.); (E.B.)
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11
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Fuentes N, McCullough M, Panettieri RA, Druey KM. RGS proteins, GRKs, and beta-arrestins modulate G protein-mediated signaling pathways in asthma. Pharmacol Ther 2021; 223:107818. [PMID: 33600853 DOI: 10.1016/j.pharmthera.2021.107818] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/25/2021] [Indexed: 12/17/2022]
Abstract
Asthma is a highly prevalent disorder characterized by chronic lung inflammation and reversible airways obstruction. Pathophysiological features of asthma include episodic and reversible airway narrowing due to increased bronchial smooth muscle shortening in response to external and host-derived mediators, excessive mucus secretion into the airway lumen, and airway remodeling. The aberrant airway smooth muscle (ASM) phenotype observed in asthma manifests as increased sensitivity to contractile mediators (EC50) and an increase in the magnitude of contraction (Emax); collectively these attributes have been termed "airways hyper-responsiveness" (AHR). This defining feature of asthma can be promoted by environmental factors including airborne allergens, viruses, and air pollution and other irritants. AHR reduces airway caliber and obstructs airflow, evoking clinical symptoms such as cough, wheezing and shortness of breath. G-protein-coupled receptors (GPCRs) have a central function in asthma through their impact on ASM and airway inflammation. Many but not all treatments for asthma target GPCRs mediating ASM contraction or relaxation. Here we discuss the roles of specific GPCRs, G proteins, and their associated signaling pathways, in asthma, with an emphasis on endogenous mechanisms of GPCR regulation of ASM tone and lung inflammation including regulators of G-protein signaling (RGS) proteins, G-protein coupled receptor kinases (GRKs), and β-arrestin.
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Affiliation(s)
- Nathalie Fuentes
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH, Bethesda, MD, United States of America
| | - Morgan McCullough
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH, Bethesda, MD, United States of America
| | - Reynold A Panettieri
- Rutgers Institute for Translational Medicine and Science, Child Health Institute of New Jersey, Rutgers University School of Medicine, New Brunswick, NJ, United States of America
| | - Kirk M Druey
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH, Bethesda, MD, United States of America.
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12
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Schroer AB, Branyan KW, Gross JD, Chantler PD, Kimple AJ, Vandenbeuch A, Siderovski DP. The stability of tastant detection by mouse lingual chemosensory tissue requires Regulator of G protein Signaling-21 (RGS21). Chem Senses 2021; 46:6414340. [PMID: 34718440 DOI: 10.1093/chemse/bjab048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The T1R and T2R families of G protein-coupled receptors (GPCRs) initiate tastant perception by signaling via guanine nucleotide exchange and hydrolysis performed by associated heterotrimeric G proteins (Gαβγ). Heterotrimeric G protein signal termination is sped up by Gα-directed GTPase-accelerating proteins (GAPs) known as the Regulators of G protein Signaling (RGS proteins). Of this family, RGS21 is highly expressed in lingual epithelial cells and we have shown it acting in vitro to decrease the potency of bitterants on cultured cells. However, constitutive RGS21 loss in mice reduces organismal response to GPCR-mediated tastants-opposite to expectations arising from observed in vitro activity of RGS21 as a GAP and inhibitor of T2R signaling. Here, we show reduced quinine aversion and reduced sucrose preference by mice lacking RGS21 does not result from post-ingestive effects, as taste-salient brief-access tests confirm the reduced bitterant aversion and reduced sweetener preference seen using two-bottle choice testing. Eliminating Rgs21 expression after chemosensory system development, via tamoxifen-induced Cre recombination in eight week-old mice, led to a reduction in quinine aversive behavior that advanced over time, suggesting that RGS21 functions as a negative regulator to sustain stable bitter tastant reception. Consistent with this notion, we observed downregulation of multiple T2R proteins in the lingual tissue of Rgs21-deficient mice. Reduced tastant-mediated responses exhibited by mice lacking Rgs21 expression either since birth or in adulthood has highlighted the potential requirement for a GPCR GAP to maintain the full character of tastant signaling, likely at the level of mitigating receptor downregulation.
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Affiliation(s)
- Adam B Schroer
- Department of Neuroscience, West Virginia University School of Medicine, 64 Medical Center Drive, Morgantown, WV 26506, USA
| | - Kayla W Branyan
- Division of Exercise Physiology, West Virginia University School of Medicine, 64 Medical Center Drive, Morgantown, WV 26506, USA
| | - Joshua D Gross
- Department of Cell Biology, Duke University Medical Center, 307 Research Drive, Durham, NC 27710, USA
| | - Paul D Chantler
- Division of Exercise Physiology, West Virginia University School of Medicine, 64 Medical Center Drive, Morgantown, WV 26506, USA
| | - Adam J Kimple
- Department of Otolaryngology and Marsico Lung Institute, UNC School of Medicine , 170 Manning Drive, Chapel Hill, NC 27599-7070, USA
| | - Aurelie Vandenbeuch
- Department of Otolaryngology, University of Colorado-Denver, Anschutz Medical Campus, 12700 E. 19th Avenue, Aurora, CO 80045, USA
| | - David P Siderovski
- Department of Pharmacology & Neuroscience, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX 76107, USA
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13
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Sun Y, Zhang D, Ma ML, Lin H, Song Y, Wang J, Ma C, Yu K, An W, Guo S, He D, Yang Z, Xiao P, Hou G, Yu X, Sun JP. Optimization of a peptide ligand for the adhesion GPCR ADGRG2 provides a potent tool to explore receptor biology. J Biol Chem 2020; 296:100174. [PMID: 33303626 PMCID: PMC7948503 DOI: 10.1074/jbc.ra120.014726] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 12/06/2020] [Accepted: 12/10/2020] [Indexed: 12/11/2022] Open
Abstract
The adhesion GPCR ADGRG2, also known as GPR64, is a critical regulator of male fertility that maintains ion/pH homeostasis and CFTR coupling. The molecular basis of ADGRG2 function is poorly understood, in part because no endogenous ligands for ADGRG2 have been reported, thus limiting the tools available to interrogate ADGRG2 activity. It has been shown that ADGRG2 can be activated by a peptide, termed p15, derived from its own N-terminal region known as the Stachel sequence. However, the low affinity of p15 limits its utility for ADGRG2 characterization. In the current study, we used alanine scanning mutagenesis to examine the critical residues responsible for p15-induced ADGRG2 activity. We next designed systematic strategies to optimize the peptide agonist of ADGRG2, using natural and unnatural amino acid substitutions. We obtained an optimized ADGRG2 Stachel peptide T1V/F3Phe(4-Me) (VPM-p15) that activated ADGRG2 with significantly improved (>2 orders of magnitude) affinity. We then characterized the residues in ADGRG2 that were important for ADGRG2 activation in response to VPM-p15 engagement, finding that the toggle switch W6.53 and residues of the ECL2 region of ADGRG2 are key determinants for VPM-p15 interactions and VPM-p15-induced Gs or arrestin signaling. Our study not only provides a useful tool to investigate the function of ADGRG2 but also offers new insights to guide further optimization of Stachel peptides to activate adhesion GPCR members.
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Affiliation(s)
- Yujing Sun
- School of Pharmacy, Binzhou Medical University, Yantai, Shandong, China; Department of Endocrinology, Cheeloo College of Medicine, Qilu Hospital, Shandong University, Jinan, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Daolai Zhang
- School of Pharmacy, Binzhou Medical University, Yantai, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Ming-Liang Ma
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Hui Lin
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Youchen Song
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Junyan Wang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Chuanshun Ma
- School of Pharmacy, Binzhou Medical University, Yantai, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Ke Yu
- School of Pharmacy, Binzhou Medical University, Yantai, Shandong, China
| | - Wentao An
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Shengchao Guo
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Dongfang He
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Zhao Yang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Peng Xiao
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Guige Hou
- School of Pharmacy, Binzhou Medical University, Yantai, Shandong, China
| | - Xiao Yu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China.
| | - Jin-Peng Sun
- School of Pharmacy, Binzhou Medical University, Yantai, Shandong, China; Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Key Laboratory of Molecular Cardiovascular Science, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Ministry of Education, Beijing, China.
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14
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Masuho I, Balaji S, Muntean BS, Skamangas NK, Chavali S, Tesmer JJG, Babu MM, Martemyanov KA. A Global Map of G Protein Signaling Regulation by RGS Proteins. Cell 2020; 183:503-521.e19. [PMID: 33007266 PMCID: PMC7572916 DOI: 10.1016/j.cell.2020.08.052] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 07/03/2020] [Accepted: 08/29/2020] [Indexed: 12/24/2022]
Abstract
The control over the extent and timing of G protein signaling is provided by the regulator of G protein signaling (RGS) proteins that deactivate G protein α subunits (Gα). Mammalian genomes encode 20 canonical RGS and 16 Gα genes with key roles in physiology and disease. To understand the principles governing the selectivity of Gα regulation by RGS, we examine the catalytic activity of all canonical human RGS proteins and their selectivity for a complete set of Gα substrates using real-time kinetic measurements in living cells. The data reveal rules governing RGS-Gα recognition, the structural basis of its selectivity, and provide principles for engineering RGS proteins with defined selectivity. The study also explores the evolution of RGS-Gα selectivity through ancestral reconstruction and demonstrates how naturally occurring non-synonymous variants in RGS alter signaling. These results provide a blueprint for decoding signaling selectivity and advance our understanding of molecular recognition principles. Systematic analysis reveals G protein selectivity of all canonical RGS proteins RGS proteins rely on selectivity bar codes for selective G protein recognition Transplantation of bar codes across RGS proteins switches their G protein preferences Natural variants, mutations, and evolution shape RGS selectivity
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Affiliation(s)
- Ikuo Masuho
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Santhanam Balaji
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK; Departments of Structural Biology and Center for Data Driven Discovery, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Brian S Muntean
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Nickolas K Skamangas
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Sreenivas Chavali
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK; Department of Biology, Indian Institute of Science Education and Research (IISER) Tirupati, Karakambadi Road, Tirupati 517 507, India
| | - John J G Tesmer
- Departments of Biological Sciences and Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907-2054, USA
| | - M Madan Babu
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK; Departments of Structural Biology and Center for Data Driven Discovery, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Kirill A Martemyanov
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA.
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15
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Kaski SW, Brooks S, Wen S, Haut MW, Siderovski DP, Berry JH, Lander LR, Setola V. Four single nucleotide polymorphisms in genes involved in neuronal signaling are associated with Opioid Use Disorder in West Virginia. J Opioid Manag 2019; 15:103-109. [PMID: 31057342 DOI: 10.5055/jom.2019.0491] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Objective Pilot study to assess utility in opioid use disorder (OUD) of a panel of single nucleotide polymorphisms in genes previously related to substance use disorder (SUD) and/or phenotypes that predispose individuals to OUD/SUD. Design Genetic association study. Setting West Virginia University's Chestnut Ridge Center Comprehensive Opioid Abuse Treatment (COAT) clinic for individuals diagnosed with OUD. Patients Sixty patients 18 years of age or older with OUD undergoing medication (buprenorphine/naloxone)-assisted treatment (MAT); all sixty patients recruited contributed samples for genetic analysis. Outcome Measures Minor allele frequencies for single nucleotide polymorphisms. Results Four of the fourteen single nucleotide polymorphisms examined were present at frequencies that are statistically significantly different than in a demographically-matched general population. Conclusions For the purposes of testing WV individuals via genetic means for predisposition to OUD, at least four single nucleotide polymorphisms in three genes are likely to have utility in predicting susceptibility. Additional studies with larger populations will need to be conducted to confirm these results before use in a clinical setting.
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Affiliation(s)
- Shane W Kaski
- Department of Physiology & Pharmacology, West Virginia University School of Medicine, Morgantown, WV
| | | | - Sijin Wen
- Department of Biostatistics, West Virginia University School of Public Health, Morgantown, WV
| | - Marc W Haut
- Department of Behavioral Medicine & Psychiatry, West Virginia University School of Medicine, Morgantown, WV
| | - David P Siderovski
- Department of Physiology & Pharmacology, West Virginia University School of Medicine, Morgantown, WV
| | - James H Berry
- Chestnut Ridge Center and Inpatient Acute Dual Diagnosis Program, West Virginia University School of Medicine, Morgantown, WV
| | - Laura R Lander
- West Virginia University School of Medicine, Morgantown, WV
| | - Vincent Setola
- Departments of Behavioral Medicine & Psychiatry, Neuroscience, and Physiology & Pharmacology, West Virginia University School of Medicine, Morgantown, WV
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16
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Sieng M, Hayes MP, O'Brien JB, Andrew Fowler C, Houtman JC, Roman DL, Lyon AM. High-resolution structure of RGS17 suggests a role for Ca 2+ in promoting the GTPase-activating protein activity by RZ subfamily members. J Biol Chem 2019; 294:8148-8160. [PMID: 30940727 DOI: 10.1074/jbc.ra118.006059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 03/27/2019] [Indexed: 11/06/2022] Open
Abstract
Regulator of G protein signaling (RGS) proteins are negative regulators of G protein-coupled receptor (GPCR) signaling through their ability to act as GTPase-activating proteins (GAPs) for activated Gα subunits. Members of the RZ subfamily of RGS proteins bind to activated Gαo, Gαz, and Gαi1-3 proteins in the nervous system and thereby inhibit downstream pathways, including those involved in Ca2+-dependent signaling. In contrast to other RGS proteins, little is known about RZ subfamily structure and regulation. Herein, we present the 1.5-Å crystal structure of RGS17, the most complete and highest-resolution structure of an RZ subfamily member to date. RGS17 cocrystallized with Ca2+ bound to conserved positions on the predicted Gα-binding surface of the protein. Using NMR chemical shift perturbations, we confirmed that Ca2+ binds in solution to the same site. Furthermore, RGS17 had greater than 55-fold higher affinity for Ca2+ than for Mg2+ Finally, we found that Ca2+ promotes interactions between RGS17 and activated Gα and decreases the Km for GTP hydrolysis, potentially by altering the binding mechanism between these proteins. Taken together, these findings suggest that Ca2+ positively regulates RGS17, which may represent a general mechanism by which increased Ca2+ concentration promotes the GAP activity of the RZ subfamily, leading to RZ-mediated inhibition of Ca2+ signaling.
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Affiliation(s)
- Monita Sieng
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907
| | - Michael P Hayes
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa 52242
| | - Joseph B O'Brien
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa 52242
| | - C Andrew Fowler
- NMR Facility, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Jon C Houtman
- Department of Microbiology and Immunology, University of Iowa, Iowa City, Iowa 52242
| | - David L Roman
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa 52242
| | - Angeline M Lyon
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907; Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907.
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17
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George T, Chakraborty M, Giembycz MA, Newton R. A bronchoprotective role for Rgs2 in a murine model of lipopolysaccharide-induced airways inflammation. Allergy Asthma Clin Immunol 2018; 14:40. [PMID: 30305828 PMCID: PMC6166284 DOI: 10.1186/s13223-018-0266-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 05/22/2018] [Indexed: 02/07/2023] Open
Abstract
Background Asthma exacerbations are associated with the recruitment of neutrophils to the lungs. These cells release proteases and mediators, many of which act at G protein-coupled receptors (GPCRs) that couple via Gq to promote bronchoconstriction and inflammation. Common asthma therapeutics up-regulate expression of the regulator of G protein signalling (RGS), RGS2. As RGS2 reduces signaling from Gq-coupled GPCRs, we have defined role(s) for this GTPase-activating protein in an acute neutrophilic model of lung inflammation. Methods Wild type and Rgs2−/− C57Bl6 mice were exposed to nebulized lipopolysaccharide (LPS). Lung function (respiratory system resistance and compliance) was measured using a SCIREQ flexivent small animal ventilator. Lung inflammation was assessed by histochemistry, cell counting and by cytokine and chemokine expression in bronchoalveolar lavage (BAL) fluid. Results Lipopolysaccharide inhalation induced transient airways hyperreactivity (AHR) and neutrophilic lung inflammation. While AHR and inflammation was greatest 3 h post-LPS exposure, BAL neutrophils persisted for 24 h. At 3 h post-LPS inhalation, multiple inflammatory cytokines (CSF2, CSF3, IL6, TNF) and chemokines (CCL3, CCL4, CXCL1, CXCL2) were highly expressed in the BAL fluid, prior to declining by 24 h. Compared to wild type counterparts, Rgs2−/− mice developed significantly greater airflow resistance in response to inhaled methacholine (MCh) at 3 h post-LPS exposure. At 24 h post-LPS exposure, when lung function was recovering in the wild type animals, MCh-induced resistance was increased, and compliance decreased, in Rgs2−/− mice. Thus, Rgs2−/− mice show AHR and stiffer lungs 24 h post-LPS exposure. Histological markers of inflammation, total and differential cell counts, and major cytokine and chemokine expression in BAL fluid were similar between wild type and Rgs2−/− mice. However, 3 and 24 h post-LPS exposure, IL12B expression was significantly elevated in BAL fluid from Rgs2−/− mice compared to wild type animals. Conclusions While Rgs2 is bronchoprotective in acute neutrophilic inflammation, no clear anti-inflammatory effect was apparent. Nevertheless, elevated IL12B expression in Rgs2−/− animals raises the possibility that RGS2 could dampen Th1 responses. These findings indicate that up-regulation of RGS2, as occurs in response to inhaled corticosteroids and long-acting β2-adrenoceptor agonists, may be beneficial in acute neutrophilic exacerbations of airway disease, including asthma. Electronic supplementary material The online version of this article (10.1186/s13223-018-0266-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tresa George
- 1Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB T2N 4Z6 Canada
| | - Mainak Chakraborty
- 2Immunology Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB T2N 4Z6 Canada
| | - Mark A Giembycz
- 1Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB T2N 4Z6 Canada
| | - Robert Newton
- 1Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB T2N 4Z6 Canada
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18
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Perschbacher KJ, Deng G, Fisher RA, Gibson-Corley KN, Santillan MK, Grobe JL. Regulators of G protein signaling in cardiovascular function during pregnancy. Physiol Genomics 2018; 50:590-604. [PMID: 29702036 PMCID: PMC6139632 DOI: 10.1152/physiolgenomics.00037.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
G protein-coupled receptor signaling mechanisms are implicated in many aspects of cardiovascular control, and dysfunction of such signaling mechanisms is commonly associated with disease states. Investigators have identified a large number of regulator of G protein signaling (RGS) proteins that variously contribute to the modulation of intracellular second-messenger signaling kinetics. These many RGS proteins each interact with a specific set of second-messenger cascades and receptor types and exhibit tissue-specific expression patterns. Increasing evidence supports the contribution of RGS proteins, or their loss, in the pathogenesis of cardiovascular dysfunctions. This review summarizes the current understanding of the functional contributions of RGS proteins, particularly within the B/R4 family, in cardiovascular disorders of pregnancy including gestational hypertension, uterine artery dysfunction, and preeclampsia.
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Affiliation(s)
| | - Guorui Deng
- Department of Pharmacology, University of Iowa , Iowa City, Iowa
| | - Rory A Fisher
- Department of Pharmacology, University of Iowa , Iowa City, Iowa
| | - Katherine N Gibson-Corley
- Department of Pathology, University of Iowa , Iowa City, Iowa
- UIHC Center for Hypertension Research, University of Iowa , Iowa City, Iowa
| | - Mark K Santillan
- Department of Obstetrics & Gynecology, University of Iowa , Iowa City, Iowa
- UIHC Center for Hypertension Research, University of Iowa , Iowa City, Iowa
- Abboud Cardiovascular Research Center, University of Iowa , Iowa City, Iowa
| | - Justin L Grobe
- Department of Pharmacology, University of Iowa , Iowa City, Iowa
- UIHC Center for Hypertension Research, University of Iowa , Iowa City, Iowa
- Abboud Cardiovascular Research Center, University of Iowa , Iowa City, Iowa
- Fraternal Order of Eagles' Diabetes Research Center, University of Iowa , Iowa City, Iowa
- Obesity Education & Research Initiative, University of Iowa , Iowa City, Iowa
- Iowa Neuroscience Institute, University of Iowa , Iowa City, Iowa
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19
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Interplay between negative and positive design elements in Gα helical domains of G proteins determines interaction specificity toward RGS2. Biochem J 2018; 475:2293-2304. [PMID: 29925530 DOI: 10.1042/bcj20180285] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 06/18/2018] [Accepted: 06/19/2018] [Indexed: 01/26/2023]
Abstract
Regulators of G protein signaling (RGS) proteins inactivate Gα subunits, thereby controlling G protein-coupled signaling networks. Among all RGS proteins, RGS2 is unique in interacting only with the Gαq but not with the Gαi subfamily. Previous studies suggested that this specificity is determined by the RGS domain and, in particular, by three RGS2-specific residues that lead to a unique mode of interaction with Gαq This interaction was further proposed to act through contacts with the Gα GTPase domain. Here, we combined energy calculations and GTPase activity measurements to determine which Gα residues dictate specificity toward RGS2. We identified putative specificity-determining residues in the Gα helical domain, which among G proteins is found only in Gα subunits. Replacing these helical domain residues in Gαi with their Gαq counterparts resulted in a dramatic specificity switch toward RGS2. We further show that Gα-RGS2 specificity is set by Gαi residues that perturb interactions with RGS2, and by Gαq residues that enhance these interactions. These results show, for the first time, that the Gα helical domain is central to dictating specificity toward RGS2, suggesting that this domain plays a general role in governing Gα-RGS specificity. Our insights provide new options for manipulating RGS-G protein interactions in vivo, for better understanding of their 'wiring' into signaling networks, and for devising novel drugs targeting such interactions.
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Hannanta-anan P, Chow BY. Optogenetic Inhibition of Gα q Protein Signaling Reduces Calcium Oscillation Stochasticity. ACS Synth Biol 2018; 7:1488-1495. [PMID: 29792810 PMCID: PMC6311707 DOI: 10.1021/acssynbio.8b00065] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As fast terminators of G-protein coupled receptor (GPCR) signaling, regulators of G-protein signaling (RGS) serve critical roles in fine-tuning second messenger levels and, consequently, cellular responses to external stimuli. Here, we report the creation of an optogenetic RGS2 (opto-RGS2) that suppresses agonist-evoked calcium oscillations by the inactivation of Gαq protein. In this system, cryptochrome-mediated heterodimerization of the catalytic RGS2-box with its N-terminal amphipathic helix reconstitutes a functional membrane-localized complex that can dynamically suppress store-operated release of calcium. Engineered opto-RGS2 cell lines were used to establish the role of RGS2 as a key inhibitory feedback regulator of the stochasticity of the Gαq-mediated calcium spike timing. RGS2 reduced the stochasticity of carbachol-stimulated calcium oscillations, and the feedback inhibition was coupled to the global calcium elevation by calmodulin/RGS2 interactions. The identification of a critical negative feedback circuit exemplifies the utility of optogenetic approaches for interrogating RGS/GPCR biology and calcium encoding principles through temporally precise molecular gain-of-function.
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Affiliation(s)
| | - Brian Y. Chow
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104
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21
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Asli A, Sadiya I, Avital-Shacham M, Kosloff M. “Disruptor” residues in the regulator of G protein signaling (RGS) R12 subfamily attenuate the inactivation of Gα subunits. Sci Signal 2018; 11:11/534/eaan3677. [DOI: 10.1126/scisignal.aan3677] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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22
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Shashikumar N, Baithalu R, Bathla S, Ali S, Rawat P, Kumaresan A, Kumar S, Maharana B, Singh G, Puneeth Kumar D, Singh S, Lathwal S, Jaiswal L, Mohanty T, Mohanty A. Global proteomic analysis of water buffalo ( Bubalus bubalis ) saliva at different stages of estrous cycle using high throughput mass spectrometry. Theriogenology 2018; 110:52-60. [DOI: 10.1016/j.theriogenology.2017.12.046] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 12/30/2017] [Accepted: 12/30/2017] [Indexed: 01/07/2023]
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23
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Zhang DL, Sun YJ, Ma ML, Wang YJ, Lin H, Li RR, Liang ZL, Gao Y, Yang Z, He DF, Lin A, Mo H, Lu YJ, Li MJ, Kong W, Chung KY, Yi F, Li JY, Qin YY, Li J, Thomsen ARB, Kahsai AW, Chen ZJ, Xu ZG, Liu M, Li D, Yu X, Sun JP. Gq activity- and β-arrestin-1 scaffolding-mediated ADGRG2/CFTR coupling are required for male fertility. eLife 2018; 7:e33432. [PMID: 29393851 PMCID: PMC5839696 DOI: 10.7554/elife.33432] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 01/30/2018] [Indexed: 12/23/2022] Open
Abstract
Luminal fluid reabsorption plays a fundamental role in male fertility. We demonstrated that the ubiquitous GPCR signaling proteins Gq and β-arrestin-1 are essential for fluid reabsorption because they mediate coupling between an orphan receptor ADGRG2 (GPR64) and the ion channel CFTR. A reduction in protein level or deficiency of ADGRG2, Gq or β-arrestin-1 in a mouse model led to an imbalance in pH homeostasis in the efferent ductules due to decreased constitutive CFTR currents. Efferent ductule dysfunction was rescued by the specific activation of another GPCR, AGTR2. Further mechanistic analysis revealed that β-arrestin-1 acts as a scaffold for ADGRG2/CFTR complex formation in apical membranes, whereas specific residues of ADGRG2 confer coupling specificity for different G protein subtypes, this specificity is critical for male fertility. Therefore, manipulation of the signaling components of the ADGRG2-Gq/β-arrestin-1/CFTR complex by small molecules may be an effective therapeutic strategy for male infertility.
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Affiliation(s)
- Dao-Lai Zhang
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
- School of PharmacyBinzhou Medical UniversityYantaiChina
| | - Yu-Jing Sun
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Ming-Liang Ma
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Yi-jing Wang
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Hui Lin
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Rui-Rui Li
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Zong-Lai Liang
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Yuan Gao
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Zhao Yang
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Dong-Fang He
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Amy Lin
- Department of BiochemistrySchool of Medicine, Duke UniversityDurhamUnited States
| | - Hui Mo
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Yu-Jing Lu
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Meng-Jing Li
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Wei Kong
- Key Laboratory of Molecular Cardiovascular Science, Department of Physiology and PathophysiologySchool of Basic Medical Sciences, Peking UniversityBeijingChina
| | | | - Fan Yi
- Department of PharmacologyShandong University School of MedicineJinanChina
| | - Jian-Yuan Li
- Key Laboratory of Male Reproductive Health, National Research Institute for Family PlanningNational Health and Family Planning CommissionBeijingChina
| | - Ying-Ying Qin
- National Research Center for Assisted Reproductive Technology and Reproductive GeneticsShandong UniversityJinanChina
| | - Jingxin Li
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Alex R B Thomsen
- Department of BiochemistrySchool of Medicine, Duke UniversityDurhamUnited States
| | - Alem W Kahsai
- Department of BiochemistrySchool of Medicine, Duke UniversityDurhamUnited States
| | - Zi-Jiang Chen
- National Research Center for Assisted Reproductive Technology and Reproductive GeneticsShandong UniversityJinanChina
| | - Zhi-Gang Xu
- Shandong Provincial Key Laboratory of Animal Cells and Developmental BiologyShandong University School of Life SciencesJinanChina
| | - Mingyao Liu
- Shanghai Key Laboratory of Regulatory Biology, School of Life SciencesInstitute of Biomedical Sciences, East China Normal UniversityShanghaiChina
- Department of Molecular and Cellular Medicine, Institute of Biosciences and TechnologyTexas A&M University Health Science CenterHoustonUnited States
| | - Dali Li
- Shanghai Key Laboratory of Regulatory Biology, School of Life SciencesInstitute of Biomedical Sciences, East China Normal UniversityShanghaiChina
| | - Xiao Yu
- Department of PhysiologyShandong University School of MedicineJinanChina
| | - Jin-Peng Sun
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular BiologyShandong University School of MedicineJinanChina
- Department of BiochemistrySchool of Medicine, Duke UniversityDurhamUnited States
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24
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Kanai SM, Edwards AJ, Rurik JG, Osei-Owusu P, Blumer KJ. Proteolytic degradation of regulator of G protein signaling 2 facilitates temporal regulation of G q/11 signaling and vascular contraction. J Biol Chem 2017; 292:19266-19278. [PMID: 28974581 DOI: 10.1074/jbc.m117.797134] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 09/18/2017] [Indexed: 12/18/2022] Open
Abstract
Regulator of G protein signaling 2 (RGS2) controls signaling by receptors coupled to the Gq/11 class heterotrimeric G proteins. RGS2 deficiency causes several phenotypes in mice and occurs in several diseases, including hypertension in which a proteolytically unstable RGS2 mutant has been reported. However, the mechanisms and functions of RGS2 proteolysis remain poorly understood. Here we addressed these questions by identifying degradation signals in RGS2, and studying dynamic regulation of Gq/11-evoked Ca2+ signaling and vascular contraction. We identified a novel bipartite degradation signal in the N-terminal domain of RGS2. Mutations disrupting this signal blunted proteolytic degradation downstream of E3 ubiquitin ligase binding to RGS2. Analysis of RGS2 mutants proteolyzed at various rates and the effects of proteasome inhibition indicated that proteolytic degradation controls agonist efficacy by setting RGS2 protein expression levels, and affecting the rate at which cells regain agonist responsiveness as synthesis of RGS2 stops. Analyzing contraction of mesenteric resistance arteries supported the biological relevance of this mechanism. Because RGS2 mRNA expression often is strikingly and transiently up-regulated and then down-regulated upon cell stimulation, our findings indicate that proteolytic degradation tightly couples RGS2 transcription, protein levels, and function. Together these mechanisms provide tight temporal control of Gq/11-coupled receptor signaling in the cardiovascular, immune, and nervous systems.
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Affiliation(s)
- Stanley M Kanai
- From the Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110 and
| | - Alethia J Edwards
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19102
| | - Joel G Rurik
- From the Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110 and
| | - Patrick Osei-Owusu
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19102
| | - Kendall J Blumer
- From the Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110 and
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25
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Kumar BA, Kumari P, Sona C, Yadav PN. GloSensor assay for discovery of GPCR-selective ligands. Methods Cell Biol 2017; 142:27-50. [PMID: 28964338 DOI: 10.1016/bs.mcb.2017.07.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
G protein-coupled receptors (GPCRs) are modulators of almost every physiological process, and therefore, are most favorite therapeutic target for wide spectrum of diseases. Ideally, high-throughput functional assays should be implemented that allow the screening of large compound libraries in cost-effective manner to identify agonist, antagonist, and allosteric modulators in the same assay. Taking advantage of the increased understanding of the GPCR structure and signaling, several commercially available functional assays based on fluorescence or chemiluminescence detection are being used in both academia and industry. In this chapter, we provide step-by-step method and guidelines to perform cAMP measurement using GloSensor assay. Finally, we have also discussed the analysis and interpretation of results obtained using this assay by providing several examples of Gs- and Gi-coupled GPCRs.
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Affiliation(s)
- Boda Arun Kumar
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Poonam Kumari
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Chandan Sona
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
| | - Prem N Yadav
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi, India.
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26
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Zhu Y, Jiang YH, He YP, Zhang X, Sun ZG, Jiang MX, Wang J. Knockdown of regulator of G-protein signalling 2 (Rgs2) leads to abnormal early mouse embryo development in vitro. Reprod Fertil Dev 2017; 27:557-66. [PMID: 24524188 DOI: 10.1071/rd13269] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 01/16/2014] [Indexed: 11/23/2022] Open
Abstract
Regulator of G-protein signalling 2 (Rgs2) is involved in G-protein-mediated signalling by negatively regulating the activity of the G-protein α-subunit. In the present study, the expression patterns of Rgs2 in mouse ovarian tissues and early embryos were determined by semiquantitative reverse transcription-polymerase chain reaction, immunohistochemistry and immunofluorescent analyses. Rgs2 expression was observed in the ovarian tissues of adult female mice, with an almost equal expression levels during different stages of the oestrous cycle. Rgs2 was abundant in the cytoplasm, membrane, nuclei and spindles of intact polar bodies in mouse early embryos at different developmental stages from the zygote to blastocyst. The effect of Rgs2 knockdown on early embryonic development in vitro was examined by microinjecting Rgs2-specific short interfering (si) RNAs into mouse zygotes. Knockdown of endogenous Rgs2 expression led to abnormal embryonic development in vitro, with a considerable number of early embryos arrested at the 2- or 4-cell stage. Moreover, mRNA expression of three zygotic gene activation-related genes (i.e. Zscan4, Tcstv1 and MuERV-L) was decreased significantly in 2-cell arrested embryos. These results suggest that Rgs2 plays a critical role in early embryo development.
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Affiliation(s)
- Yan Zhu
- Key Laboratory of Contraceptive Drugs and Devices of National Population and Family Planning Committee, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
| | - Ya-Hong Jiang
- Key Laboratory of Contraceptive Drugs and Devices of National Population and Family Planning Committee, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
| | - Ya-Ping He
- Key Laboratory of Contraceptive Drugs and Devices of National Population and Family Planning Committee, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
| | - Xuan Zhang
- Key Laboratory of Contraceptive Drugs and Devices of National Population and Family Planning Committee, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
| | - Zhao-Gui Sun
- Key Laboratory of Contraceptive Drugs and Devices of National Population and Family Planning Committee, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
| | - Man-Xi Jiang
- Department of Laboratory Animal Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Jian Wang
- Key Laboratory of Contraceptive Drugs and Devices of National Population and Family Planning Committee, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
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27
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George T, Bell M, Chakraborty M, Siderovski DP, Giembycz MA, Newton R. Protective Roles for RGS2 in a Mouse Model of House Dust Mite-Induced Airway Inflammation. PLoS One 2017; 12:e0170269. [PMID: 28107494 PMCID: PMC5249169 DOI: 10.1371/journal.pone.0170269] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 12/30/2016] [Indexed: 12/16/2022] Open
Abstract
The GTPase-accelerating protein, regulator of G-protein signalling 2 (RGS2) reduces signalling from G-protein-coupled receptors (GPCRs) that signal via Gαq. In humans, RGS2 expression is up-regulated by inhaled corticosteroids (ICSs) and long-acting β2-adrenoceptor agonists (LABAs) such that synergy is produced in combination. This may contribute to the superior clinical efficacy of ICS/LABA therapy in asthma relative to ICS alone. In a murine model of house dust mite (HDM)-induced airways inflammation, three weeks of intranasal HDM (25 μg, 3×/week) reduced lung function and induced granulocytic airways inflammation. Compared to wild type animals, Rgs2-/- mice showed airways hyperresponsiveness (increased airways resistance and reduced compliance). While HDM increased pulmonary inflammation observed on hematoxylin and eosin-stained sections, there was no difference between wild type and Rgs2-/- animals. HDM-induced mucus hypersecretion was also unaffected by RGS2 deficiency. However, inflammatory cell counts in the bronchoalveolar lavage fluid of Rgs2-/- animals were significantly increased (57%) compared to wild type animals and this correlated with increased granulocyte (neutrophil and eosinophil) numbers. Likewise, cytokine and chemokine (IL4, IL17, IL5, LIF, IL6, CSF3, CXCLl, CXCL10 and CXCL11) release was increased by HDM exposure. Compared to wild type, Rgs2-/- animals showed a trend towards increased expression for many cytokines/chemokines, with CCL3, CCL11, CXCL9 and CXCL10 being significantly enhanced. As RGS2 expression was unaffected by HDM exposure, these data indicate that RGS2 exerts tonic bronchoprotection in HDM-induced airways inflammation. Modest anti-inflammatory and anti-remodelling roles for RGS2 are also suggested. If translatable to humans, therapies that maximize RGS2 expression may prove advantageous.
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Affiliation(s)
- Tresa George
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Matthew Bell
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Mainak Chakraborty
- Immunology Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - David P. Siderovski
- Blanchette Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia, United States of America
| | - Mark A. Giembycz
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
- * E-mail:
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28
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Chen X, McCorvy JD, Fischer MG, Butler KV, Shen Y, Roth BL, Jin J. Discovery of G Protein-Biased D2 Dopamine Receptor Partial Agonists. J Med Chem 2016; 59:10601-10618. [PMID: 27805392 PMCID: PMC5148701 DOI: 10.1021/acs.jmedchem.6b01208] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Biased ligands (also known as functionally selective ligands) of G protein-coupled receptors are valuable tools for dissecting the roles of G protein-dependent and independent signaling pathways in health and disease. Biased ligands have also been increasingly pursued by the biomedical community as promising therapeutics with improved efficacy and reduced side effects compared with unbiased ligands. We previously discovered first-in-class β-arrestin-biased agonists of dopamine D2 receptor (D2R) by extensively exploring multiple regions of aripiprazole, a balanced D2R agonist. In our continuing efforts to identify biased agonists of D2R, we unexpectedly discovered a G protein-biased agonist of D2R, compound 1, which is the first G protein-biased D2R agonist from the aripiprazole scaffold. We designed and synthesized novel analogues to explore two regions of 1 and conducted structure-functional selectivity relationship (SFSR) studies. Here we report the discovery of 1, findings from our SFSR studies, and characterization of novel G protein-biased D2R agonists.
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Affiliation(s)
- Xin Chen
- Departments of Pharmacological Sciences and Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, New York 10029, USA
| | - John D. McCorvy
- Department of Pharmacology and National Institute of Mental Health Psychoactive Drug Screening Program, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Matthew G. Fischer
- Departments of Pharmacological Sciences and Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, New York 10029, USA
| | - Kyle V. Butler
- Departments of Pharmacological Sciences and Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, New York 10029, USA
| | - Yudao Shen
- Departments of Pharmacological Sciences and Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, New York 10029, USA
| | - Bryan L. Roth
- Department of Pharmacology and National Institute of Mental Health Psychoactive Drug Screening Program, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Jian Jin
- Departments of Pharmacological Sciences and Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, New York 10029, USA
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Newton R, Giembycz MA. Understanding how long-acting β 2 -adrenoceptor agonists enhance the clinical efficacy of inhaled corticosteroids in asthma - an update. Br J Pharmacol 2016; 173:3405-3430. [PMID: 27646470 DOI: 10.1111/bph.13628] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 08/19/2016] [Accepted: 08/21/2016] [Indexed: 12/18/2022] Open
Abstract
In moderate-to-severe asthma, adding an inhaled long-acting β2 -adenoceptor agonist (LABA) to an inhaled corticosteroid (ICS) provides better disease control than simply increasing the dose of ICS. Acting on the glucocorticoid receptor (GR, gene NR3C1), ICSs promote anti-inflammatory/anti-asthma gene expression. In vitro, LABAs synergistically enhance the maximal expression of many glucocorticoid-induced genes. Other genes, including dual-specificity phosphatase 1(DUSP1) in human airways smooth muscle (ASM) and epithelial cells, are up-regulated additively by both drug classes. Synergy may also occur for LABA-induced genes, as illustrated by the bronchoprotective gene, regulator of G-protein signalling 2 (RGS2) in ASM. Such effects cannot be produced by either drug alone and may explain the therapeutic efficacy of ICS/LABA combination therapies. While the molecular basis of synergy remains unclear, mechanistic interpretations must accommodate gene-specific regulation. We explore the concept that each glucocorticoid-induced gene is an independent signal transducer optimally activated by a specific, ligand-directed, GR conformation. In addition to explaining partial agonism, this realization provides opportunities to identify novel GR ligands that exhibit gene expression bias. Translating this into improved therapeutic ratios requires consideration of GR density in target tissues and further understanding of gene function. Similarly, the ability of a LABA to interact with a glucocorticoid may be suboptimal due to low β2 -adrenoceptor density or biased β2 -adrenoceptor signalling. Strategies to overcome these limitations include adding-on a phosphodiesterase inhibitor and using agonists of other Gs-coupled receptors. In all cases, the rational design of ICS/LABA, and derivative, combination therapies requires functional knowledge of induced (and repressed) genes for therapeutic benefit to be maximized.
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Affiliation(s)
- Robert Newton
- Department of Cell Biology and Anatomy, Airways Inflammation Research Group, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Mark A Giembycz
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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30
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Young A, Dandekar U, Pan C, Sader A, Zheng JJ, Lewis RA, Farber DB. GNAI3: Another Candidate Gene to Screen in Persons with Ocular Albinism. PLoS One 2016; 11:e0162273. [PMID: 27607449 PMCID: PMC5015898 DOI: 10.1371/journal.pone.0162273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 08/21/2016] [Indexed: 11/18/2022] Open
Abstract
Ocular albinism type 1 (OA), caused by mutations in the OA1 gene, encodes a G-protein coupled receptor, OA1, localized in melanosomal membranes of the retinal pigment epithelium (RPE). This disorder is characterized by both RPE macro-melanosomes and abnormal decussation of ganglion cell axons at the brain's optic chiasm. We demonstrated previously that Oa1 specifically activates Gαi3, which also signals in the Oa1 transduction pathway that regulates melanosomal biogenesis. In this study, we screened the human Gαi3 gene, GNAI3, in DNA samples from 26 patients who had all clinical characteristics of OA but in whom a specific mutation in the OA1 gene had not been found, and in 6 normal control individuals. Using the Agilent HaloPlex Target Enrichment System and next-generation sequencing (NGS) on the Illumina MiSeq platform, we identified 518 variants after rigorous filtering. Many of these variants were corroborated by Sanger sequencing. Overall, 98.8% coverage of the GNAI3 gene was obtained by the HaloPlex amplicons. Of all variants, 6 non-synonymous and 3 synonymous were in exons, 41 in a non-coding exon embedded in the 3' untranslated region (UTR), 6 in the 5' UTR, and 462 in introns. These variants included novel SNVs, insertions, deletions, and a frameshift mutation. All were found in at least one patient but none in control samples. Using computational methods, we modeled the GNAI3 protein and its non-synonymous exonic mutations and determined that several of these may be the cause of disease in the patients studied. Thus, we have identified GNAI3 as a second gene possibly responsible for X-linked ocular albinism.
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Affiliation(s)
- Alejandra Young
- Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine, UCLA, Los Angeles, CA, United States of America
- Molecular Biology Institute, UCLA, Los Angeles, CA, United States of America
| | - Uma Dandekar
- UCLA-GenoSeq Core, UCLA, Los Angeles, CA, United States of America
| | - Calvin Pan
- UCLA-GenoSeq Core, UCLA, Los Angeles, CA, United States of America
| | - Avery Sader
- Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine, UCLA, Los Angeles, CA, United States of America
| | - Jie J. Zheng
- Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine, UCLA, Los Angeles, CA, United States of America
| | - Richard A. Lewis
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States of America
| | - Debora B. Farber
- Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine, UCLA, Los Angeles, CA, United States of America
- Molecular Biology Institute, UCLA, Los Angeles, CA, United States of America
- Brain Research Institute, UCLA, Los Angeles, CA, United States of America
- * E-mail:
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31
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Jiang MX, Shi Y, Sun ZG, Zhang Z, Zhu Y. Inhibition of the Binding between RGS2 and β-Tubulin Interferes with Spindle Formation and Chromosome Segregation during Mouse Oocyte Maturation In Vitro. PLoS One 2016; 11:e0159535. [PMID: 27463806 PMCID: PMC4963123 DOI: 10.1371/journal.pone.0159535] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 07/04/2016] [Indexed: 11/18/2022] Open
Abstract
RGS2 is a negative regulator of G protein signaling that contains a GTPase-activating domain and a β-tubulin binding region. This study aimed to determine the localization and function of RGS2 during mouse oocyte maturation in vitro. Immunofluorescent staining revealed that RGS2 was widely expressed in the cytoplasm with a greater abundance on both meiotic spindles and first/second polar bodies from the fully-grown germinal vesicle (GV) stage to the MII stages. Co-expression of RGS2 and β-tubulin could also be detected in the spindle and polar body of mouse oocytes at the MI, AI, and MII stages. Inhibition of the binding site between RGS2 and β-tubulin was accomplished by injecting anti-RGS2 antibody into GV-stage oocytes, which could result in oocytes arrest at the MI or AI stage during in vitro maturation, but it did not affect germinal vesicle breakdown. Moreover, injecting anti-RGS2 antibody into oocytes resulted in a significant reduction in the rate of first polar body extrusion and abnormal spindle formation. Additionally, levels of phosphorylated MEK1/2 were significantly reduced in anti-RGS2 antibody injected oocytes compared with control oocytes. These findings suggest that RGS2 might play a critical role in mouse oocyte meiotic maturation by affecting β-tubulin polymerization and chromosome segregation.
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Affiliation(s)
- Man-Xi Jiang
- Guangdong No.2 Provincial People’s Hospital, Guangzhou 510317, China
| | - Yan Shi
- NPFPC Key Lab of Contraceptives and Devices, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
| | - Zhao-Gui Sun
- NPFPC Key Lab of Contraceptives and Devices, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
| | - Zhi Zhang
- Guangdong No.2 Provincial People’s Hospital, Guangzhou 510317, China
- * E-mail: (YZ); (ZZ)
| | - Yan Zhu
- Guangdong No.2 Provincial People’s Hospital, Guangzhou 510317, China
- * E-mail: (YZ); (ZZ)
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Taylor VG, Bommarito PA, Tesmer JJG. Structure of the Regulator of G Protein Signaling 8 (RGS8)-Gαq Complex: MOLECULAR BASIS FOR Gα SELECTIVITY. J Biol Chem 2016; 291:5138-45. [PMID: 26755720 DOI: 10.1074/jbc.m115.712075] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Indexed: 11/06/2022] Open
Abstract
Regulator of G protein signaling (RGS) proteins interact with activated Gα subunits via their RGS domains and accelerate the hydrolysis of GTP. Although the R4 subfamily of RGS proteins generally accepts both Gαi/o and Gαq/11 subunits as substrates, the R7 and R12 subfamilies select against Gαq/11. In contrast, only one RGS protein, RGS2, is known to be selective for Gαq/11. The molecular basis for this selectivity is not clear. Previously, the crystal structure of RGS2 in complex with Gαq revealed a non-canonical interaction that could be due to interfacial differences imposed by RGS2, the Gα subunit, or both. To resolve this ambiguity, the 2.6 Å crystal structure of RGS8, an R4 subfamily member, was determined in complex with Gαq. RGS8 adopts the same pose on Gαq as it does when bound to Gαi3, indicating that the non-canonical interaction of RGS2 with Gαq is due to unique features of RGS2. Based on the RGS8-Gαq structure, residues in RGS8 that contact a unique α-helical domain loop of Gαq were converted to those typically found in R12 subfamily members, and the reverse substitutions were introduced into RGS10, an R12 subfamily member. Although these substitutions perturbed their ability to stimulate GTP hydrolysis, they did not reverse selectivity. Instead, selectivity for Gαq seems more likely determined by whether strong contacts can be maintained between α6 of the RGS domain and Switch III of Gαq, regions of high sequence and conformational diversity in both protein families.
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Affiliation(s)
- Veronica G Taylor
- From the Life Sciences Institute and the Departments of Pharmacology and Biological Sciences, and the Program in Biophysics, University of Michigan, Ann Arbor, Michigan 48109
| | - Paige A Bommarito
- From the Life Sciences Institute and the Departments of Pharmacology and Biological Sciences, and
| | - John J G Tesmer
- From the Life Sciences Institute and the Departments of Pharmacology and Biological Sciences, and
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BinMahfouz H, Borthakur B, Yan D, George T, Giembycz MA, Newton R. Superiority of combined phosphodiesterase PDE3/PDE4 inhibition over PDE4 inhibition alone on glucocorticoid- and long-acting β2-adrenoceptor agonist-induced gene expression in human airway epithelial cells. Mol Pharmacol 2014; 87:64-76. [PMID: 25324049 DOI: 10.1124/mol.114.093393] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Glucocorticoids, also known as corticosteroids, induce effector gene transcription as a part of their anti-inflammatory mechanisms of action. Such genomic effects can be significantly enhanced by long-acting β2-adrenoceptor agonists (LABAs) and may contribute to the clinical superiority of inhaled corticosteroid (ICS)/LABA combinations in asthma and chronic obstructive pulmonary disease (COPD) over ICSs alone. Using models of cAMP- and glucocorticoid-induced transcription in human bronchial epithelial BEAS-2B cells, we show that combining inhibitors of phosphodiesterase (PDE) 3 and PDE4 provides greater benefits compared with inhibiting either PDE alone. In respect to cAMP-dependent transcription, inhibitors of PDE3 (siguazodan, cilostazol) and PDE4 (rolipram, GSK256066, roflumilast N-oxide) each sensitized to the LABA, formoterol. This effect was magnified by dual PDE3 and PDE4 inhibition. Siguazodan plus rolipram was also more effective at inducing cAMP-dependent transcription than either inhibitor alone. Conversely, the concentration-response curve describing the enhancement of dexamethasone-induced, glucocorticoid response element-dependent transcription by formoterol was displaced to the left by PDE4, but not PDE3, inhibition. Overall, similar effects were described for bona fide genes, including RGS2, CD200, and CRISPLD2. Importantly, the combination of siguazodan plus rolipram prolonged the duration of gene expression induced by formoterol, dexamethasone, or dexamethasone plus formoterol. This was most apparent for RGS2, a bronchoprotective gene that may also reduce the proinflammatory effects of constrictor mediators. Collectively, these data provide a rationale for the use of PDE3 and PDE4 inhibitors in the treatment of COPD and asthma where they may enhance, sensitize, and prolong the effects of LABA/ICS combination therapies.
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Affiliation(s)
- Hawazen BinMahfouz
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Bibhusana Borthakur
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Dong Yan
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Tresa George
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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ADEBIYI ADEBOWALE. RGS2 regulates urotensin II-induced intracellular Ca2+ elevation and contraction in glomerular mesangial cells. J Cell Physiol 2014; 229:502-11. [PMID: 24105430 PMCID: PMC11250777 DOI: 10.1002/jcp.24470] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 09/06/2013] [Indexed: 01/01/2023]
Abstract
Urotensin II (UII), a vasoactive peptide modulates renal hemodynamics. However, the physiological functions of UII in glomerular cells are unclear. In particular, whether UII alters mesangial tone remains largely unknown. The present study investigates the physiological effects of UII on glomerular mesangial cells (GMCs). This study also tested the hypothesis that the regulator of G-protein signaling (RGS) controls UII receptor (UTR) activity in GMCs. RT-PCR, Western immunoblotting, and immunofluorescence revealed UTR expression in cultured murine GMCs. Mouse UII (mUII) stimulated Ca(2+) release from intracellular stores and activated store-operated Ca(2+) entry (SOCE) in the cells. mUII also caused a reduction in planar GMC surface area. mUII-induced [Ca(2+)]i elevation and contraction were attenuated by SB 657510, a UTR antagonist, araguspongin B, an inositol 1,4,5-trisphosphate receptor antagonist, thapsigargin, a sarco/endoplasmic reticulum Ca(2+)-ATPase inhibitor, and La(3+), a store-operated Ca(2+) channel blocker, but not nimodipine, an L-type Ca(2+) channel blocker. In situ proximity ligation assay indicated molecular proximity between endogenous RGS2 and UTR in the cells. Treatment of GMCs with mUII elevated plasma membrane expression of RGS2 by ∼2-fold. mUII also increased the interaction between RGS2 and UTR in the cells. siRNA-mediated knockdown of RGS2 in murine GMCs increased mUII-induced [Ca(2+)]i elevation and contraction by ∼35 and 31%, respectively. These findings indicate that mUII-induced SOCE results in murine GMC contraction. These data also suggest that UTR activation stimulates RGS2 recruitment to GMC plasma membrane as a negative feedback mechanism to regulate UTR signaling.
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Affiliation(s)
- ADEBOWALE ADEBIYI
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
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A proteomic view to characterize the effect of chitosan nanoparticle to hepatic cells: is chitosan nanoparticle an enhancer of PI3K/AKT1/mTOR pathway? BIOMED RESEARCH INTERNATIONAL 2014; 2014:789591. [PMID: 24757677 PMCID: PMC3976794 DOI: 10.1155/2014/789591] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 02/10/2014] [Indexed: 11/23/2022]
Abstract
Chitosan nanoparticle, a biocompatible material, was used as a potential drug delivery system widely. Our current investigation studies were the bioeffects of the chitosan nanoparticle uptake by liver cells. In this experiment, the characterizations of chitosan nanoparticles were measured by transmission electron microscopy and particle size analyzer. The average size of the chitosan nanoparticle was 224.6 ± 11.2 nm, and the average zeta potential was +14.08 ± 0.7 mV. Moreover, using proteomic approaches to analyze the differential protein expression patterns resulted from the chitosan nanoparticle uptaken by HepG2 and CCL-13 cells identified several proteins involved in the PI3K/AKT1/mTOR pathway. Our experimental results have demonstrated that the chitosan nanoparticle may involve in the liver cancer cell metastasis and proliferation.
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Schunter C, Vollmer SV, Macpherson E, Pascual M. Transcriptome analyses and differential gene expression in a non-model fish species with alternative mating tactics. BMC Genomics 2014; 15:167. [PMID: 24581002 PMCID: PMC4029132 DOI: 10.1186/1471-2164-15-167] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Accepted: 02/20/2014] [Indexed: 12/22/2022] Open
Abstract
Background Social dominance is important for the reproductive success of males in many species. In the black-faced blenny (Tripterygion delaisi) during the reproductive season, some males change color and invest in nest making and defending a territory, whereas others do not change color and ‘sneak’ reproductions when females lay their eggs. Using RNAseq, we profiled differential gene expression between the brains of territorial males, sneaker males, and females to study the molecular signatures of male dimorphism. Results We found that more genes were differentially expressed between the two male phenotypes than between males and females, suggesting that during the reproductive period phenotypic plasticity is a more important factor in differential gene expression than sexual dimorphism. The territorial male overexpresses genes related to synaptic plasticity and the sneaker male overexpresses genes involved in differentiation and development. Conclusions Previously suggested candidate genes for social dominance in the context of alternative mating strategies seem to be predominantly species-specific. We present a list of novel genes which are differentially expressed in Tripterygion delaisi. This is the first genome-wide study for a molecular non-model species in the context of alternative mating strategies and provides essential information for further studies investigating the molecular basis of social dominance.
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Affiliation(s)
- Celia Schunter
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Car, Acc, Cala St, Francesc 14 Blanes 17300 Girona, Spain.
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Holden NS, George T, Rider CF, Chandrasekhar A, Shah S, Kaur M, Johnson M, Siderovski DP, Leigh R, Giembycz MA, Newton R. Induction of regulator of G-protein signaling 2 expression by long-acting β2-adrenoceptor agonists and glucocorticoids in human airway epithelial cells. J Pharmacol Exp Ther 2013; 348:12-24. [PMID: 24163441 DOI: 10.1124/jpet.113.204586] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
In asthma and chronic obstructive pulmonary disease (COPD) multiple mediators act on Gαq-linked G-protein-coupled receptors (GPCRs) to cause bronchoconstriction. However, acting on the airway epithelium, such mediators may also elicit inflammatory responses. In human bronchial epithelial BEAS-2B cells (bronchial epithelium + adenovirus 12-SV40 hybrid), regulator of G-protein signaling (RGS) 2 mRNA and protein were synergistically induced in response to combinations of long-acting β2-adrenoceptor agonist (LABA) (salmeterol, formoterol) plus glucocorticoid (dexamethasone, fluticasone propionate, budesonide). Equivalent responses occurred in primary human bronchial epithelial cells. Concentrations of glucocorticoid plus LABA required to induce RGS2 expression in BEAS-2B cells were consistent with the levels achieved therapeutically in the lungs. As RGS2 is a GTPase-activating protein that switches off Gαq, intracellular free calcium ([Ca(2+)]i) flux was used as a surrogate of responses induced by histamine, methacholine, and the thromboxane receptor agonist U46619 [(Z)-7-[(1S,4R,5R,6S)-5-[(E,3S)-3-hydroxyoct-1-enyl]-3-oxabicyclo[2.2.1]heptan-6-yl]hept-5-enoic acid]. This was significantly attenuated by salmeterol plus dexamethasone pretreatment, or RGS2 overexpression, and the protective effect of salmeterol plus dexamethasone was abolished by RGS2 RNA silencing. Although methacholine and U46619 induced interleukin-8 (IL-8) release and this was inhibited by RGS2 overexpression, the repression of U46619-induced IL-8 release by salmeterol plus dexamethasone was unaffected by RGS2 knockdown. Given a role for Gαq-mediated pathways in inducing IL-8 release, we propose that RGS2 acts redundantly with other effector processes to repress IL-8 expression. Thus, RGS2 expression is a novel effector mechanism in the airway epithelium that is induced by glucocorticoid/LABA combinations. This could contribute to the efficacy of glucocorticoid/LABA combinations in asthma and COPD.
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Affiliation(s)
- Neil S Holden
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada (N.S.H., T.G., C.F.R., A.C., S.S., M.K., R.L., M.A.G., R.N.); GlaxoSmithKline Research and Development, Uxbridge, Middlesex, United Kingdom (M.J.); and Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia (D.P.S.)
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38
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Kimple AJ, Garland AL, Cohen SP, Setola V, Willard FS, Zielinski T, Lowery RG, Tarran R, Siderovski DP. RGS21, a regulator of taste and mucociliary clearance? Laryngoscope 2013; 124:E56-63. [PMID: 23908053 DOI: 10.1002/lary.24326] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/27/2013] [Accepted: 07/05/2013] [Indexed: 01/08/2023]
Abstract
OBJECTIVES/HYPOTHESIS Motile cilia of airway epithelial cells help to expel harmful inhaled material. Activation of bitterant-responsive G protein-coupled receptors (GPCRs) is believed to potentiate cilia beat frequency and mucociliary clearance. In this study, we investigated whether regulator of G protein signaling-21 (RGS21) has the potential to modulate signaling pathways connected to airway mucociliary clearance, given that RGS proteins modulate GPCR signaling by acting as GTPase-accelerating proteins (GAPs) for the Gα subunits of heterotrimeric G proteins. STUDY DESIGN This is a pilot investigation to determine if RGS21, a potential tastant specific RGS gene, is expressed in sinonasal mucosa, and to determine its specific Gα substrate using in vitro biochemical assays with purified proteins. METHODS Rgs21 expression in sinonasal mucosa was determined using quantitative, real-time PCR and a transgenic mouse expressing RFP from the Rgs21 promoter. Rgs21 was cloned, over-expressed, and purified using multistep protein chromatography. Biochemical and biophysical assays were used to determine if RGS21 could bind and accelerate the hydrolysis of GTP on heterotrimeric Gα subunits. RESULTS Rgs21 was expressed in sinonasal mucosa and lingual epithelium. Purified recombinant protein directly bound and accelerated GTP hydrolysis on Gα subunits. CONCLUSIONS Rgs21 is expressed in sinonasal mucosa, is amenable to purification as a recombinant protein, and can bind to Gα(i/o/q) subunits. Furthermore, RGS21 can accelerate the hydrolysis rate of GTP on Gαi subunits. This provides evidence that RGS21 may be a negative regulator of bitterant responses. Future studies will be needed to determine the physiological role of this protein in mucociliary clearance.
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Affiliation(s)
- Adam J Kimple
- Department of Otolaryngology-Head and Neck Surgery, University of North Carolina at Chapel Hill, North Carolina, U.S.A; Department of Pharmacology, University of North Carolina at Chapel Hill, North Carolina, U.S.A
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Abstract
G protein-coupled receptors mediate a wide array of physiologic stimuli and, together with their regulators such as RGS2, are essential components of cellular signaling and function. RGS2 is a selective inhibitor of the Gαq class of α subunits. In this issue of Structure, Nance and colleagues provide structural insight into the features of RGS2 that mediate its potent and selective regulation of Gαq function.
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Affiliation(s)
- Scott P Heximer
- Department of Physiology, Heart and Stroke/Richard Lewar Centre of Excellence in Cardiovascular Research, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada.
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40
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Munro TA, Huang XP, Inglese C, Perrone MG, Van't Veer A, Carroll FI, Béguin C, Carlezon WA, Colabufo NA, Cohen BM, Roth BL. Selective κ opioid antagonists nor-BNI, GNTI and JDTic have low affinities for non-opioid receptors and transporters. PLoS One 2013; 8:e70701. [PMID: 23976952 PMCID: PMC3747596 DOI: 10.1371/journal.pone.0070701] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 06/21/2013] [Indexed: 01/16/2023] Open
Abstract
Background Nor-BNI, GNTI and JDTic induce selective κ opioid antagonism that is delayed and extremely prolonged, but some other effects are of rapid onset and brief duration. The transient effects of these compounds differ, suggesting that some of them may be mediated by other targets. Results In binding assays, the three antagonists showed no detectable affinity (Ki≥10 µM) for most non-opioid receptors and transporters (26 of 43 tested). There was no non-opioid target for which all three compounds shared detectable affinity, or for which any two shared sub-micromolar affinity. All three compounds showed low nanomolar affinity for κ opioid receptors, with moderate selectivity over μ and δ (3 to 44-fold). Nor-BNI bound weakly to the α2C-adrenoceptor (Ki = 630 nM). GNTI enhanced calcium mobilization by noradrenaline at the α1A-adrenoceptor (EC50 = 41 nM), but did not activate the receptor, displace radioligands, or enhance PI hydrolysis. This suggests that it is a functionally-selective allosteric enhancer. GNTI was also a weak M1 receptor antagonist (KB = 3.7 µM). JDTic bound to the noradrenaline transporter (Ki = 54 nM), but only weakly inhibited transport (IC50 = 1.1 µM). JDTic also bound to the opioid-like receptor NOP (Ki = 12 nM), but gave little antagonism even at 30 µM. All three compounds exhibited rapid permeation and active efflux across Caco-2 cell monolayers. Conclusions Across 43 non-opioid CNS targets, only GNTI exhibited a potent functional effect (allosteric enhancement of α1A-adrenoceptors). This may contribute to GNTI's severe transient effects. Plasma concentrations of nor-BNI and GNTI may be high enough to affect some peripheral non-opioid targets. Nonetheless, κ opioid antagonism persists for weeks or months after these transient effects dissipate. With an adequate pre-administration interval, our results therefore strengthen the evidence that nor-BNI, GNTI and JDTic are highly selective κ opioid antagonists.
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MESH Headings
- Allosteric Regulation
- Biological Transport
- Caco-2 Cells
- Calcium/metabolism
- Guanidines/metabolism
- Guanidines/pharmacology
- Humans
- Kinetics
- Morphinans/metabolism
- Morphinans/pharmacology
- Naltrexone/analogs & derivatives
- Naltrexone/metabolism
- Naltrexone/pharmacology
- Narcotic Antagonists/metabolism
- Narcotic Antagonists/pharmacology
- Norepinephrine/metabolism
- Norepinephrine Plasma Membrane Transport Proteins/metabolism
- Piperidines/metabolism
- Piperidines/pharmacology
- Protein Binding
- Receptors, Adrenergic, alpha/metabolism
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/metabolism
- Tetrahydroisoquinolines/metabolism
- Tetrahydroisoquinolines/pharmacology
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Affiliation(s)
- Thomas A. Munro
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
- School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, Australia
- * E-mail:
| | - Xi-Ping Huang
- National Institute of Mental Health Psychoactive Drug Screening Program and Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Carmela Inglese
- Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari, Bari, Italy
| | - Maria Grazia Perrone
- Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari, Bari, Italy
| | - Ashlee Van't Veer
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
| | - F. Ivy Carroll
- Center for Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina, United States of America
| | - Cécile Béguin
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
| | - William A. Carlezon
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Nicola A. Colabufo
- Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari, Bari, Italy
| | - Bruce M. Cohen
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Bryan L. Roth
- National Institute of Mental Health Psychoactive Drug Screening Program and Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
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Park CR, Moon MJ, Park S, Kim DK, Cho EB, Millar RP, Hwang JI, Seong JY. A novel glucagon-related peptide (GCRP) and its receptor GCRPR account for coevolution of their family members in vertebrates. PLoS One 2013; 8:e65420. [PMID: 23776481 PMCID: PMC3679108 DOI: 10.1371/journal.pone.0065420] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 04/24/2013] [Indexed: 12/25/2022] Open
Abstract
The glucagon (GCG) peptide family consists of GCG, glucagon-like peptide 1 (GLP1), and GLP2, which are derived from a common GCG precursor, and the glucose-dependent insulinotropic polypeptide (GIP). These peptides interact with cognate receptors, GCGR, GLP1R, GLP2R, and GIPR, which belong to the secretin-like G protein-coupled receptor (GPCR) family. We used bioinformatics to identify genes encoding a novel GCG-related peptide (GCRP) and its cognate receptor, GCRPR. The GCRP and GCRPR genes were found in representative tetrapod taxa such as anole lizard, chicken, and Xenopus, and in teleosts including medaka, fugu, tetraodon, and stickleback. However, they were not present in mammals and zebrafish. Phylogenetic and genome synteny analyses showed that GCRP emerged through two rounds of whole genome duplication (2R) during early vertebrate evolution. GCRPR appears to have arisen by local tandem gene duplications from a common ancestor of GCRPR, GCGR, and GLP2R after 2R. Biochemical ligand-receptor interaction analyses revealed that GCRP had the highest affinity for GCRPR in comparison to other GCGR family members. Stimulation of chicken, Xenopus, and medaka GCRPRs activated Gαs-mediated signaling. In contrast to chicken and Xenopus GCRPRs, medaka GCRPR also induced Gαq/11-mediated signaling. Chimeric peptides and receptors showed that the K16M17K18 and G16Q17A18 motifs in GCRP and GLP1, respectively, may at least in part contribute to specific recognition of their cognate receptors through interaction with the receptor core domain. In conclusion, we present novel data demonstrating that GCRP and GCRPR evolved through gene/genome duplications followed by specific modifications that conferred selective recognition to this ligand-receptor pair.
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Affiliation(s)
- Cho Rong Park
- Laboratory of G-protein Coupled Receptors, Graduate School of Medicine Korea University, Seoul, Republic of Korea
| | - Mi Jin Moon
- Laboratory of G-protein Coupled Receptors, Graduate School of Medicine Korea University, Seoul, Republic of Korea
| | - Sumi Park
- Laboratory of G-protein Coupled Receptors, Graduate School of Medicine Korea University, Seoul, Republic of Korea
| | - Dong-Kyu Kim
- Laboratory of G-protein Coupled Receptors, Graduate School of Medicine Korea University, Seoul, Republic of Korea
| | - Eun Bee Cho
- Laboratory of G-protein Coupled Receptors, Graduate School of Medicine Korea University, Seoul, Republic of Korea
| | - Robert Peter Millar
- Mammal Research Institute, Department of Zoology & Entomology, University of Pretoria, Hatfield, South Africa
- Medical Research Council Receptor Biology Unit, University of Cape Town, Observatory 7925, South Africa
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, Scotland
| | - Jong-Ik Hwang
- Laboratory of G-protein Coupled Receptors, Graduate School of Medicine Korea University, Seoul, Republic of Korea
- * E-mail: (JIH); (JYS)
| | - Jae Young Seong
- Laboratory of G-protein Coupled Receptors, Graduate School of Medicine Korea University, Seoul, Republic of Korea
- * E-mail: (JIH); (JYS)
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Baltoumas FA, Theodoropoulou MC, Hamodrakas SJ. Interactions of the α-subunits of heterotrimeric G-proteins with GPCRs, effectors and RGS proteins: A critical review and analysis of interacting surfaces, conformational shifts, structural diversity and electrostatic potentials. J Struct Biol 2013; 182:209-18. [DOI: 10.1016/j.jsb.2013.03.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 03/06/2013] [Accepted: 03/11/2013] [Indexed: 01/05/2023]
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Park DW, Lyu JH, Kim JS, Chin H, Bae YS, Baek SH. Role of JAK2-STAT3 in TLR2-mediated tissue factor expression. J Cell Biochem 2013; 114:1315-21. [DOI: 10.1002/jcb.24472] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 11/27/2012] [Indexed: 11/10/2022]
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Farrell MS, Pei Y, Wan Y, Yadav PN, Daigle TL, Urban DJ, Lee HM, Sciaky N, Simmons A, Nonneman RJ, Huang XP, Hufeisen SJ, Guettier JM, Moy SS, Wess J, Caron MG, Calakos N, Roth BL. A Gαs DREADD mouse for selective modulation of cAMP production in striatopallidal neurons. Neuropsychopharmacology 2013; 38:854-62. [PMID: 23303063 PMCID: PMC3671990 DOI: 10.1038/npp.2012.251] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 11/19/2012] [Accepted: 11/22/2012] [Indexed: 01/11/2023]
Abstract
Here, we describe a newly generated transgenic mouse in which the Gs DREADD (rM3Ds), an engineered G protein-coupled receptor, is selectively expressed in striatopallidal medium spiny neurons (MSNs). We first show that in vitro, rM3Ds can couple to Gαolf and induce cAMP accumulation in cultured neurons and HEK-T cells. The rM3Ds was then selectively and stably expressed in striatopallidal neurons by creating a transgenic mouse in which an adenosine2A (adora2a) receptor-containing bacterial artificial chromosome was employed to drive rM3Ds expression. In the adora2A-rM3Ds mouse, activation of rM3Ds by clozapine-N-oxide (CNO) induces DARPP-32 phosphorylation, consistent with the known consequence of activation of endogenous striatal Gαs-coupled GPCRs. We then tested whether CNO administration would produce behavioral responses associated with striatopallidal Gs signaling and in this regard CNO dose-dependently decreases spontaneous locomotor activity and inhibits novelty induced locomotor activity. Last, we show that CNO prevented behavioral sensitization to amphetamine and increased AMPAR/NMDAR ratios in transgene-expressing neurons of the nucleus accumbens shell. These studies demonstrate the utility of adora2a-rM3Ds transgenic mice for the selective and noninvasive modulation of Gαs signaling in specific neuronal populations in vivo.This unique tool provides a new resource for elucidating the roles of striatopallidal MSN Gαs signaling in other neurobehavioral contexts.
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Affiliation(s)
- Martilias S Farrell
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Ying Pei
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Yehong Wan
- Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Prem N Yadav
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Tanya L Daigle
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
| | - Daniel J Urban
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Hyeong-Min Lee
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Noah Sciaky
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Arkeen Simmons
- Elizabeth City State University, Elizabeth City, NC, USA
| | - Randal J Nonneman
- Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC, USA
| | - Xi-Ping Huang
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Sandy J Hufeisen
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
| | - Jean-Marc Guettier
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, NIH-NIDDK, Bethesda, MD, USA
| | - Sheryl S Moy
- Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC, USA
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, NIH-NIDDK, Bethesda, MD, USA
| | - Marc G Caron
- Department of Medicine, Duke University Medical Center, Durham, NC, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC, USA
| | - Nicole Calakos
- Department of Medicine, Duke University Medical Center, Durham, NC, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC, USA
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, USA
- Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC, USA
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
- Program in Neuroscience, University of North Carolina, Chapel Hill, NC, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
- Division of Chemical Biology and Medicinal Chemistry, School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
- NIMH Psychoactive Drug Screening Program, University of North Carolina, Chapel Hill, NC, USA
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Nance MR, Kreutz B, Tesmer VM, Sterne-Marr R, Kozasa T, Tesmer JJG. Structural and functional analysis of the regulator of G protein signaling 2-gαq complex. Structure 2013; 21:438-48. [PMID: 23434405 DOI: 10.1016/j.str.2012.12.016] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 11/20/2012] [Accepted: 12/13/2012] [Indexed: 10/27/2022]
Abstract
The heterotrimeric G protein Gαq is a key regulator of blood pressure, and excess Gαq signaling leads to hypertension. A specific inhibitor of Gαq is the GTPase activating protein (GAP) known as regulator of G protein signaling 2 (RGS2). The molecular basis for how Gαq/11 subunits serve as substrates for RGS proteins and how RGS2 mandates its selectivity for Gαq is poorly understood. In crystal structures of the RGS2-Gαq complex, RGS2 docks to Gαq in a different orientation from that observed in RGS-Gαi/o complexes. Despite its unique pose, RGS2 maintains canonical interactions with the switch regions of Gαq in part because its α6 helix adopts a distinct conformation. We show that RGS2 forms extensive interactions with the α-helical domain of Gαq that contribute to binding affinity and GAP potency. RGS subfamilies that do not serve as GAPs for Gαq are unlikely to form analogous stabilizing interactions.
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Affiliation(s)
- Mark R Nance
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109-2216, USA
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Cohen SP, Buckley BK, Kosloff M, Garland AL, Bosch DE, Cheng G, Radhakrishna H, Brown MD, Willard FS, Arshavsky VY, Tarran R, Siderovski DP, Kimple AJ. Regulator of G-protein signaling-21 (RGS21) is an inhibitor of bitter gustatory signaling found in lingual and airway epithelia. J Biol Chem 2012; 287:41706-19. [PMID: 23095746 DOI: 10.1074/jbc.m112.423806] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The gustatory system detects tastants and transmits signals to the brain regarding ingested substances and nutrients. Although tastant receptors and taste signaling pathways have been identified, little is known about their regulation. Because bitter, sweet, and umami taste receptors are G protein-coupled receptors (GPCRs), we hypothesized that regulators of G protein signaling (RGS) proteins may be involved. The recent cloning of RGS21 from taste bud cells has implicated this protein in the regulation of taste signaling; however, the exact role of RGS21 has not been precisely defined. Here, we sought to determine the role of RGS21 in tastant responsiveness. Biochemical analyses confirmed in silico predictions that RGS21 acts as a GTPase-accelerating protein (GAP) for multiple G protein α subunits, including adenylyl cyclase-inhibitory (Gα(i)) subunits and those thought to be involved in tastant signal transduction. Using a combination of in situ hybridization, RT-PCR, immunohistochemistry, and immunofluorescence, we demonstrate that RGS21 is not only endogenously expressed in mouse taste buds but also in lung airway epithelial cells, which have previously been shown to express components of the taste signaling cascade. Furthermore, as shown by reverse transcription-PCR, the immortalized human airway cell line 16HBE was found to express transcripts for tastant receptors, RGS21, and downstream taste signaling components. Over- and underexpression of RGS21 in 16HBE cells confirmed that RGS21 acts to oppose bitter tastant signaling to cAMP and calcium second messenger changes. Our data collectively suggests that RGS21 modulates bitter taste signal transduction.
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Affiliation(s)
- Staci P Cohen
- Department of Pharmacology, University of North Carolina Neuroscience Center, University of North Carolina, Chapel Hill, North Carolina 27599-7365, USA
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Structure of the nociceptin/orphanin FQ receptor in complex with a peptide mimetic. Nature 2012; 485:395-9. [PMID: 22596163 PMCID: PMC3356928 DOI: 10.1038/nature11085] [Citation(s) in RCA: 386] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 03/30/2012] [Indexed: 01/07/2023]
Abstract
Members of the opioid receptor family of G-protein-coupled receptors (GPCRs) are found throughout the peripheral and central nervous system, where they have key roles in nociception and analgesia. Unlike the 'classical' opioid receptors, δ, κ and μ (δ-OR, κ-OR and μ-OR), which were delineated by pharmacological criteria in the 1970s and 1980s, the nociceptin/orphanin FQ (N/OFQ) peptide receptor (NOP, also known as ORL-1) was discovered relatively recently by molecular cloning and characterization of an orphan GPCR. Although it shares high sequence similarity with classical opioid GPCR subtypes (∼60%), NOP has a markedly distinct pharmacology, featuring activation by the endogenous peptide N/OFQ, and unique selectivity for exogenous ligands. Here we report the crystal structure of human NOP, solved in complex with the peptide mimetic antagonist compound-24 (C-24) (ref. 4), revealing atomic details of ligand-receptor recognition and selectivity. Compound-24 mimics the first four amino-terminal residues of the NOP-selective peptide antagonist UFP-101, a close derivative of N/OFQ, and provides important clues to the binding of these peptides. The X-ray structure also shows substantial conformational differences in the pocket regions between NOP and the classical opioid receptors κ (ref. 5) and μ (ref. 6), and these are probably due to a small number of residues that vary between these receptors. The NOP-compound-24 structure explains the divergent selectivity profile of NOP and provides a new structural template for the design of NOP ligands.
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Rieder M, Green G, Park S, Stamper B, Gordon C, Johnson J, Cunniff C, Smith J, Emery S, Lyonnet S, Amiel J, Holder M, Heggie A, Bamshad M, Nickerson D, Cox T, Hing A, Horst J, Cunningham M. A human homeotic transformation resulting from mutations in PLCB4 and GNAI3 causes auriculocondylar syndrome. Am J Hum Genet 2012; 90:907-14. [PMID: 22560091 DOI: 10.1016/j.ajhg.2012.04.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 02/10/2012] [Accepted: 04/03/2012] [Indexed: 10/28/2022] Open
Abstract
Auriculocondylar syndrome (ACS) is a rare, autosomal-dominant craniofacial malformation syndrome characterized by variable micrognathia, temporomandibular joint ankylosis, cleft palate, and a characteristic "question-mark" ear malformation. Careful phenotypic characterization of severely affected probands in our cohort suggested the presence of a mandibular patterning defect resulting in a maxillary phenotype (i.e., homeotic transformation). We used exome sequencing of five probands and identified two novel (exclusive to the patient and/or family studied) missense mutations in PLCB4 and a shared mutation in GNAI3 in two unrelated probands. In confirmatory studies, three additional novel PLCB4 mutations were found in multigenerational ACS pedigrees. All mutations were confirmed by Sanger sequencing, were not present in more than 10,000 control chromosomes, and resulted in amino-acid substitutions located in highly conserved protein domains. Additionally, protein-structure modeling demonstrated that all ACS substitutions disrupt the catalytic sites of PLCB4 and GNAI3. We suggest that PLCB4 and GNAI3 are core signaling molecules of the endothelin-1-distal-less homeobox 5 and 6 (EDN1-DLX5/DLX6) pathway. Functional studies demonstrated a significant reduction in downstream DLX5 and DLX6 expression in ACS cases in assays using cultured osteoblasts from probands and controls. These results support the role of the previously implicated EDN1-DLX5/6 pathway in regulating mandibular specification in other species, which, when disrupted, results in a maxillary phenotype. This work defines the molecular basis of ACS as a homeotic transformation (mandible to maxilla) in humans.
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Bosch DE, Willard FS, Ramanujam R, Kimple AJ, Willard MD, Naqvi NI, Siderovski DP. A P-loop mutation in Gα subunits prevents transition to the active state: implications for G-protein signaling in fungal pathogenesis. PLoS Pathog 2012; 8:e1002553. [PMID: 22383884 PMCID: PMC3285607 DOI: 10.1371/journal.ppat.1002553] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 01/12/2012] [Indexed: 11/26/2022] Open
Abstract
Heterotrimeric G-proteins are molecular switches integral to a panoply of different physiological responses that many organisms make to environmental cues. The switch from inactive to active Gαβγ heterotrimer relies on nucleotide cycling by the Gα subunit: exchange of GTP for GDP activates Gα, whereas its intrinsic enzymatic activity catalyzes GTP hydrolysis to GDP and inorganic phosphate, thereby reverting Gα to its inactive state. In several genetic studies of filamentous fungi, such as the rice blast fungus Magnaporthe oryzae, a G42R mutation in the phosphate-binding loop of Gα subunits is assumed to be GTPase-deficient and thus constitutively active. Here, we demonstrate that Gα(G42R) mutants are not GTPase deficient, but rather incapable of achieving the activated conformation. Two crystal structure models suggest that Arg-42 prevents a typical switch region conformational change upon Gαi1(G42R) binding to GDP·AlF4− or GTP, but rotameric flexibility at this locus allows for unperturbed GTP hydrolysis. Gα(G42R) mutants do not engage the active state-selective peptide KB-1753 nor RGS domains with high affinity, but instead favor interaction with Gβγ and GoLoco motifs in any nucleotide state. The corresponding Gαq(G48R) mutant is not constitutively active in cells and responds poorly to aluminum tetrafluoride activation. Comparative analyses of M. oryzae strains harboring either G42R or GTPase-deficient Q/L mutations in the Gα subunits MagA or MagB illustrate functional differences in environmental cue processing and intracellular signaling outcomes between these two Gα mutants, thus demonstrating the in vivo functional divergence of G42R and activating G-protein mutants. Heterotrimeric G-proteins function as molecular switches to convey cellular signals. When a G-protein coupled receptor encounters its ligand at the cellular membrane, it catalyzes guanine nucleotide exchange on the Gα subunit, resulting in a shift from an inactive to an active conformation. G-protein signaling pathways are conserved from mammals to plants and fungi, including the rice blast fungus Magnaporthe oryzae. A mutation in the Gα subunit (G42R), previously thought to eliminate its GTPase activity, leading to constitutive activation, has been utilized to investigate roles of heterotrimeric G-protein signaling pathways in multiple species of filamentous fungi. Here, we demonstrate through structural, biochemical, and cellular approaches that G42R mutants are neither GTPase deficient nor constitutively active, but rather are unable to transition to the activated conformation. A direct comparison of M. oryzae fungal strains harboring either G42R or truly constitutively activating mutations in two Gα subunits, MagA and MagB, revealed markedly different phenotypes. Our results suggest that activation of MagB is critical for pathogenic development of M. oryzae in response to hydrophobic surfaces, such as plant leaves. Furthermore, the lack of constitutive activity by Gα(G42R) mutants prompts a re-evaluation of its use in previous genetic experiments in multiple fungal species.
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Affiliation(s)
- Dustin E. Bosch
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Francis S. Willard
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail: (FSW); (DPS)
| | - Ravikrishna Ramanujam
- Fungal Patho-Biology Group, Temasek Life Sciences Laboratory, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Adam J. Kimple
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Melinda D. Willard
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Naweed I. Naqvi
- Fungal Patho-Biology Group, Temasek Life Sciences Laboratory, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore
| | - David P. Siderovski
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- UNC Neuroscience Center and Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail: (FSW); (DPS)
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50
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Osei-Owusu P, Sabharwal R, Kaltenbronn KM, Rhee MH, Chapleau MW, Dietrich HH, Blumer KJ. Regulator of G protein signaling 2 deficiency causes endothelial dysfunction and impaired endothelium-derived hyperpolarizing factor-mediated relaxation by dysregulating Gi/o signaling. J Biol Chem 2012; 287:12541-9. [PMID: 22354966 DOI: 10.1074/jbc.m111.332130] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Regulator of G protein signaling 2 (RGS2) is a GTPase-activating protein for G(q/11)α and G(i/o)α subunits. RGS2 deficiency is linked to hypertension in mice and humans, although causative mechanisms are not understood. Because endothelial dysfunction and increased peripheral resistance are hallmarks of hypertension, determining whether RGS2 regulates microvascular reactivity may reveal mechanisms relevant to cardiovascular disease. Here we have determined the effects of systemic versus endothelium- or vascular smooth muscle-specific deletion of RGS2 on microvascular contraction and relaxation. Contraction and relaxation of mesenteric resistance arteries were analyzed in response to phenylephrine, sodium nitroprusside, or acetylcholine with or without inhibitors of nitric oxide (NO) synthase or K(+) channels that mediate endothelium-derived hyperpolarizing factor (EDHF)-dependent relaxation. The results showed that deleting RGS2 in vascular smooth muscle had minor effects. Systemic or endothelium-specific deletion of RGS2 strikingly inhibited acetylcholine-evoked relaxation. Endothelium-specific deletion of RGS2 had little effect on NO-dependent relaxation but markedly impaired EDHF-dependent relaxation. Acute, inducible deletion of RGS2 in endothelium did not affect blood pressure significantly. Impaired EDHF-mediated vasodilatation was rescued by blocking G(i/o)α activation with pertussis toxin. These findings indicated that systemic or endothelium-specific RGS2 deficiency causes endothelial dysfunction resulting in impaired EDHF-dependent vasodilatation. RGS2 deficiency enables endothelial G(i/o) activity to inhibit EDHF-dependent relaxation, whereas RGS2 sufficiency facilitates EDHF-evoked relaxation by squelching endothelial G(i/o) activity. Mutation or down-regulation of RGS2 in hypertension patients therefore may contribute to endothelial dysfunction and defective EDHF-dependent relaxation. Blunting G(i/o) signaling might improve endothelial function in such patients.
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Affiliation(s)
- Patrick Osei-Owusu
- Department of Cell Biology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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