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Trujillo EN, Flores BA, Romero IV, Moran JA, Leka A, Ramirez AD, Ear J, Mercer F. Complement receptor 3 is required for maximum in vitro trogocytic killing of the parasite Trichomonas vaginalis by human neutrophil-like cells. Parasite Immunol 2024; 46:e13025. [PMID: 38372623 PMCID: PMC11090219 DOI: 10.1111/pim.13025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/12/2024] [Accepted: 01/14/2024] [Indexed: 02/20/2024]
Abstract
Trichomonas vaginalis (Tv) is a parasite that causes trichomoniasis, a prevalent sexually-transmitted infection. Neutrophils are found at the site of infection, and can rapidly kill the parasite in vitro, using trogocytosis. However, the specific molecular players in neutrophil killing of Tv are unknown. Here, we show that complement proteins play a role in Tv killing by human neutrophil-like cells (NLCs). Using CRISPR/Cas9, we generated NLCs deficient in each of three complement receptors (CRs) known to be expressed on human neutrophils: CR1, CR3, and CR4. Using in vitro trogocytosis assays, we found that CR3, but not CR1 or CR4 is required for maximum trogocytosis of the parasite by NLCs, with NLCs lacking CR3 demonstrating ~40% reduction in trogocytosis, on average. We also observed a reduction in NLC killing of Tv in CR3 knockout, but not CR1 or CR4 knockout NLCs. On average, NLCs lacking CR3 had ~50% reduction in killing activity. We also used a parallel approach of pre-incubating NLCs with blocking antibodies against CR3, which similarly reduced NLC killing of parasites. These data support a model in which Tv is opsonized by the complement protein iC3b, and bound by neutrophil CR3 receptor, to facilitate trogocytic killing of the parasite.
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Affiliation(s)
- Emma N. Trujillo
- Department of Biological Sciences, California State Polytechnic University, Pomona, California 91768
| | - Barbara A. Flores
- Department of Biological Sciences, California State Polytechnic University, Pomona, California 91768
| | - Isabel V. Romero
- Department of Biological Sciences, California State Polytechnic University, Pomona, California 91768
| | - Jose A. Moran
- Department of Biological Sciences, California State Polytechnic University, Pomona, California 91768
| | - Aljona Leka
- Department of Biological Sciences, California State Polytechnic University, Pomona, California 91768
| | - Ashley D. Ramirez
- Department of Biological Sciences, California State Polytechnic University, Pomona, California 91768
| | - Jason Ear
- Department of Biological Sciences, California State Polytechnic University, Pomona, California 91768
| | - Frances Mercer
- Department of Biological Sciences, California State Polytechnic University, Pomona, California 91768
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Tindle C, Katkar GD, Fonseca AG, Taheri S, Lee J, Maity P, Sayed IM, Ibeawuchi SR, Vidales E, Pranadinata RF, Fuller M, Stec DL, Anandachar MS, Perry K, Le HN, Ear J, Boland BS, Sandborn WJ, Sahoo D, Das S, Ghosh P. A Living Organoid Biobank of Crohn's Disease Patients Reveals Molecular Subtypes for Personalized Therapeutics. bioRxiv 2023:2023.03.11.532245. [PMID: 36993763 PMCID: PMC10054961 DOI: 10.1101/2023.03.11.532245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Crohn's disease (CD) is a complex, clinically heterogeneous disease of multifactorial origin; there is no perfect pre-clinical model, little insight into the basis for such heterogeneity, and still no cure. To address these unmet needs, we sought to explore the translational potential of adult stem cell-derived organoids that not only retain their tissue identity, but also their genetic and epigenetic disease-driving traits. We prospectively created a biobank of CD patient-derived organoid cultures (PDOs) using biopsied tissues from colons of 34 consecutive subjects representing all clinical subtypes (Montreal Classification B1-B3 and perianal disease). PDOs were generated also from healthy subjects. Comparative gene expression analyses enabled benchmarking of PDOs as tools for modeling the colonic epithelium in active disease and revealed that despite the clinical heterogeneity there are two major molecular subtypes: immune-deficient infectious-CD [IDICD] and stress and senescence-induced fibrostenotic-CD [S2FCD]. The transcriptome, genome and phenome show a surprising degree of internal consistency within each molecular subtype. The spectrum of morphometric, phenotypic, and functional changes within the "living biobank" reveals distinct differences between the molecular subtypes. These insights enabled drug screens that reversed subtype-specific phenotypes, e.g., impaired microbial clearance in IDICD was reversed using agonists for nuclear receptors, and senescence in S2FCD was rectified using senotherapeutics, but not vice versa . Phenotyped-genotyped CD-PDOs may fill the gap between basic biology and patient trials by enabling pre-clinical Phase '0' human trials for personalized therapeutics. GRAPHIC ABSTRACT In Brief This work creates a prospectively biobanked phenotyped-genotyped Crohn's disease patient-derived organoids (CD-PDOs) as platforms for molecular subtyping of disease and for ushering personalized therapeutics. HIGHLIGHTS Prospectively biobanked CD-organoids recapitulate the disease epithelium in patientsThe phenome-transcriptome-genome of CD-organoids converge on two molecular subtypesOne subtype shows impaired microbial clearance, another increased cellular senescencePhenotyped-genotyped PDOs are then used for integrative and personalized therapeutics.
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Katkar GD, Tindle C, Fonseca A, Taheri S, Lee J, Sayed IM, Ibeawuchi SR, Rama P, Fuller M, Stec D, Anandachar MS, Goheen-Holland V, Ear J, Boland B, Sandborn W, Sahoo D, Das S, Ghosh P. A Prospectively Created Living Organoid Biobank of Crohn’s Disease Patients Enables Integrative Therapeutics. The Journal of Immunology 2022. [DOI: 10.4049/jimmunol.208.supp.115.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Abstract
Adult stem cells from various organs can be propagated as epithelial organoids that not only retain their tissue identity, but also their genetic and epigenetic disease-driving traits. We report the establishment of Crohn’s Disease (CD) patient-derived organoid cultures (PDOs) using biopsied tissues from colons of 50 consecutive subjects representing all clinical subtypes (Montreal Classification B1–B3 and perianal disease). Organoids were also generated from healthy subjects. The spectrum of phenotypic and genotypic changes within the “living biobank” agrees well with many observations reported in CD tissues. Gene expression analyses show that despite the heterogeneity of clinical subtypes, there are two major molecular subtypes, each with unique phenotypic features: immune-deficient infectious-CD [IDICD] and senescence-induced fibrostenotic-CD [SIFCD]. CD-PDOs are amenable to high-throughput drug screens allowing for the detection of phenotype reversal. As examples, defective barrier integrity in B1-PDOs was restored with pre-/pro-biotics, impaired microbial clearance in IDICD was reversed using agonists for nuclear receptors, and SIFCD was rectified using senolytics and - morphics. Phenotyped-genotyped CD-PDOs may fill the gap between basic biology and patient trials by enabling pre-clinical Phase ‘0’ human trials for personalized and integrative therapeutics.
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Affiliation(s)
- Gajanan Dattatray Katkar
- 1Cellular and Molecular Medicine, Univ. of California, San Diego
- 2HUMANOID CoRE, Univ. of California, San Diego
| | - Courtney Tindle
- 1Cellular and Molecular Medicine, Univ. of California, San Diego
- 2HUMANOID CoRE, Univ. of California, San Diego
| | - Ayden Fonseca
- 1Cellular and Molecular Medicine, Univ. of California, San Diego
- 2HUMANOID CoRE, Univ. of California, San Diego
| | - Sahar Taheri
- 3Computer Science and Engineering, Univ. of California, San Diego
| | - Jasper Lee
- 4Pathology, Univ. of California, San Diego
| | | | | | - Pranadinata Rama
- 1Cellular and Molecular Medicine, Univ. of California, San Diego
- 2HUMANOID CoRE, Univ. of California, San Diego
| | - Mackenzie Fuller
- 1Cellular and Molecular Medicine, Univ. of California, San Diego
- 2HUMANOID CoRE, Univ. of California, San Diego
| | - Dominik Stec
- 1Cellular and Molecular Medicine, Univ. of California, San Diego
- 2HUMANOID CoRE, Univ. of California, San Diego
| | | | - Vanae Goheen-Holland
- 1Cellular and Molecular Medicine, Univ. of California, San Diego
- 2HUMANOID CoRE, Univ. of California, San Diego
| | - Jason Ear
- 5Cellular and Molecular Medicine and Medicine, Univ. of California, San Diego
| | | | | | - Debashis Sahoo
- 3Computer Science and Engineering, Univ. of California, San Diego
- 7Pediatrics, Univ. of California, San Diego
| | - Soumita Das
- 2HUMANOID CoRE, Univ. of California, San Diego
- 4Pathology, Univ. of California, San Diego
| | - Pradipta Ghosh
- 1Cellular and Molecular Medicine, Univ. of California, San Diego
- 2HUMANOID CoRE, Univ. of California, San Diego
- 6Medicine, Univ. of California, San Diego
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Abd El-hafeez AA, Sun N, Chakraborty A, Ear J, Roy S, Chamarthi P, Rajapakse N, Das S, Luker KE, Hazra TK, Luker GD, Ghosh P. Regulation of DNA damage response by trimeric G-protein Signaling.. [DOI: 10.1101/2021.07.21.452842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
AbstractUpon sensing DNA double-strand breaks (DSBs), eukaryotic cells either die or repair DSBs via one of two competing pathways, i.e., non-homologous end-joining (NHEJ) or homologous recombination (HR). We show that cell fate after DNA damage hinges on the guanine nucleotide-exchange modulator of heterotrimeric G-protein, Giα•βγ, GIV/Girdin. GIV suppresses HR by binding and sequestering BRCA1, a key coordinator of multiple steps within the HR pathway, away from DSBs; it does so using a C-terminal motif that binds BRCA1’s BRCT-modules via both phospho-dependent and -independent mechanisms. GIV promotes NHEJ, and binds and activates Gi and enhances the ‘free’ Gβγ→PI-3-kinase→Akt pathway, thus revealing the enigmatic origin of prosurvival Akt signals during dsDNA repair. Absence of GIV, or the loss of either of its two functions impaired DNA repair, and induced cell death when challenged with numerous cytotoxic agents. That GIV selectively binds few other BRCT-containing proteins suggests convergent signaling such that heterotrimeric G-proteins may finetune sensing, repair, and outcome after DNA damage.GRAPHIC ABSTRACTHIGHLIGHTSNon-receptor G protein modulator, GIV/Girdin binds BRCA1Binding occurs in both canonical and non-canonical modesGIV sequesters BRCA1 away from dsDNA breaks, suppresses HRActivation of Gi by GIV enhances Akt signals, favors NHEJIN BRIEFIn this work, the authors show that heterotrimeric G protein signaling that is triggered by non-receptor GEF, GIV/Girdin, in response to double-stranded DNA breaks is critical for decisive signaling events which favor non-homologous end-joining (NHEJ) and inhibit homologous recombination (HR).
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Sharma A, Lee J, Fonseca AG, Moshensky A, Kothari T, Sayed IM, Ibeawuchi SR, Pranadinata RF, Ear J, Sahoo D, Crotty-Alexander LE, Ghosh P, Das S. E-cigarettes compromise the gut barrier and trigger inflammation. iScience 2021. [PMID: 33537654 DOI: 10.1101/2020.07.29.227348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
E-cigarette usage continues to rise, yet the safety of e-cigarette aerosols is questioned. Using murine models of acute and chronic e-cigarette aerosol inhalation, murine colon transcriptomics, and murine and human gut-derived organoids in co-culture models, we assessed the effects of e-cigarette use on the gut barrier. Histologic and transcriptome analyses revealed that chronic, but not acute, nicotine-free e-cigarette use increased inflammation and reduced expression of tight junction (TJ) markers. Exposure of murine and human enteroid-derived monolayers (EDMs) to nicotine-free e-cigarette aerosols alone or in co-culture with bacteria also causes barrier disruption, downregulation of TJ protein, and enhanced inflammation in response to infection. These data highlight the harmful effects of "non-nicotine" component of e-cigarettes on the gut barrier. Considering the importance of an intact gut barrier for host fitness and the impact of gut mucosal inflammation on a multitude of chronic diseases, these findings are broadly relevant to both medicine and public health.
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Affiliation(s)
- Aditi Sharma
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | - Jasper Lee
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | - Ayden G Fonseca
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
| | - Alex Moshensky
- Department of Medicine, University of California, San Diego, CA 92093, USA
| | - Taha Kothari
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | - Ibrahim M Sayed
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | | | - Rama F Pranadinata
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
| | - Jason Ear
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
- Department of Medicine, University of California, San Diego, CA 92093, USA
| | - Debashis Sahoo
- Department of Pediatrics, University of California, San Diego, CA 92093, USA
- Department of Computer Science and Engineering, Jacobs School of Engineering, University of California, San Diego, CA 92093, USA
- Rebecca and John Moore Comprehensive Cancer Center, University of California, San Diego, CA 92093, USA
| | - Laura E Crotty-Alexander
- Department of Medicine, University of California, San Diego, CA 92093, USA
- Veterans Affairs Medical Center, VA San Diego Healthcare System, La Jolla, San Diego, CA 92093, USA
| | - Pradipta Ghosh
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
- Department of Medicine, University of California, San Diego, CA 92093, USA
- Rebecca and John Moore Comprehensive Cancer Center, University of California, San Diego, CA 92093, USA
- Veterans Affairs Medical Center, VA San Diego Healthcare System, La Jolla, San Diego, CA 92093, USA
| | - Soumita Das
- Department of Pathology, University of California, San Diego, CA 92093, USA
- Rebecca and John Moore Comprehensive Cancer Center, University of California, San Diego, CA 92093, USA
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6
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Sharma A, Lee J, Fonseca AG, Moshensky A, Kothari T, Sayed IM, Ibeawuchi SR, Pranadinata RF, Ear J, Sahoo D, Crotty-Alexander LE, Ghosh P, Das S. E-cigarettes compromise the gut barrier and trigger inflammation. iScience 2021; 24:102035. [PMID: 33537654 PMCID: PMC7841355 DOI: 10.1016/j.isci.2021.102035] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 11/15/2020] [Accepted: 12/31/2020] [Indexed: 12/13/2022] Open
Abstract
E-cigarette usage continues to rise, yet the safety of e-cigarette aerosols is questioned. Using murine models of acute and chronic e-cigarette aerosol inhalation, murine colon transcriptomics, and murine and human gut-derived organoids in co-culture models, we assessed the effects of e-cigarette use on the gut barrier. Histologic and transcriptome analyses revealed that chronic, but not acute, nicotine-free e-cigarette use increased inflammation and reduced expression of tight junction (TJ) markers. Exposure of murine and human enteroid-derived monolayers (EDMs) to nicotine-free e-cigarette aerosols alone or in co-culture with bacteria also causes barrier disruption, downregulation of TJ protein, and enhanced inflammation in response to infection. These data highlight the harmful effects of "non-nicotine" component of e-cigarettes on the gut barrier. Considering the importance of an intact gut barrier for host fitness and the impact of gut mucosal inflammation on a multitude of chronic diseases, these findings are broadly relevant to both medicine and public health.
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Affiliation(s)
- Aditi Sharma
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | - Jasper Lee
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | - Ayden G. Fonseca
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
| | - Alex Moshensky
- Department of Medicine, University of California, San Diego, CA 92093, USA
| | - Taha Kothari
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | - Ibrahim M. Sayed
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | | | - Rama F. Pranadinata
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
| | - Jason Ear
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
- Department of Medicine, University of California, San Diego, CA 92093, USA
| | - Debashis Sahoo
- Department of Pediatrics, University of California, San Diego, CA 92093, USA
- Department of Computer Science and Engineering, Jacobs School of Engineering, University of California, San Diego, CA 92093, USA
- Rebecca and John Moore Comprehensive Cancer Center, University of California, San Diego, CA 92093, USA
| | - Laura E. Crotty-Alexander
- Department of Medicine, University of California, San Diego, CA 92093, USA
- Veterans Affairs Medical Center, VA San Diego Healthcare System, La Jolla, San Diego, CA 92093, USA
| | - Pradipta Ghosh
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
- Department of Medicine, University of California, San Diego, CA 92093, USA
- Rebecca and John Moore Comprehensive Cancer Center, University of California, San Diego, CA 92093, USA
- Veterans Affairs Medical Center, VA San Diego Healthcare System, La Jolla, San Diego, CA 92093, USA
| | - Soumita Das
- Department of Pathology, University of California, San Diego, CA 92093, USA
- Rebecca and John Moore Comprehensive Cancer Center, University of California, San Diego, CA 92093, USA
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7
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Ear J, Abd El-Hafeez AA, Roy S, Ngo T, Rajapakse N, Choi J, Khandelwal S, Ghassemian M, McCaffrey L, Kufareva I, Sahoo D, Ghosh P. A long isoform of GIV/Girdin contains a PDZ-binding module that regulates localization and G-protein binding. J Biol Chem 2021; 296:100493. [PMID: 33675748 PMCID: PMC8042451 DOI: 10.1016/j.jbc.2021.100493] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/19/2021] [Accepted: 02/26/2021] [Indexed: 11/28/2022] Open
Abstract
PDZ domains are one of the most abundant protein domains in eukaryotes and are frequently found on junction-localized scaffold proteins. Various signaling molecules bind to PDZ proteins via PDZ-binding motifs (PBM) and fine-tune cellular signaling. However, how such interaction affects protein function is difficult to predict and must be solved empirically. Here we describe a long isoform of the guanine nucleotide exchange factor GIV/Girdin (CCDC88A) that we named GIV-L, which is conserved throughout evolution, from invertebrates to vertebrates, and contains a PBM. Unlike GIV, which lacks PBM and is cytosolic, GIV-L localizes onto cell junctions and has a PDZ interactome (as shown through annotating Human Cell Map and BioID-proximity labeling studies), which impacts GIV-L's ability to bind and activate trimeric G-protein, Gαi, through its guanine-nucleotide exchange modulator (GEM) module. This GEM module is found exclusively in vertebrates. We propose that the two functional modules in GIV may have evolved sequentially: the ability to bind PDZ proteins via the PBM evolved earlier in invertebrates, whereas G-protein binding and activation may have evolved later only among vertebrates. Phenotypic studies in Caco-2 cells revealed that GIV and GIV-L may have antagonistic effects on cell growth, proliferation (cell cycle), and survival. Immunohistochemical analysis in human colon tissues showed that GIV expression increases with a concomitant decrease in GIV-L during cancer initiation. Taken together, these findings reveal how regulation in GIV/CCDC88A transcript helps to achieve protein modularity, which allows the protein to play opposing roles either as a tumor suppressor (GIV-L) or as an oncogene (GIV).
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Affiliation(s)
- Jason Ear
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA; Biological Sciences Department, California State Polytechnic University, Pomona, California, USA.
| | - Amer Ali Abd El-Hafeez
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA; Pharmacology and Experimental Oncology Unit, Cancer Biology Department, National Cancer Institute, Cairo University, Cairo, Egypt
| | - Suchismita Roy
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - Tony Ngo
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - Navin Rajapakse
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA
| | - Julie Choi
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA
| | - Soni Khandelwal
- Department of Pediatrics, University of California San Diego, La Jolla, California, USA
| | - Majid Ghassemian
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, USA
| | - Luke McCaffrey
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Canada; Gerald Bronfman Department of Oncology, McGill University, Montreal, Canada
| | - Irina Kufareva
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - Debashis Sahoo
- Department of Pediatrics, University of California San Diego, La Jolla, California, USA
| | - Pradipta Ghosh
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA; Department of Medicine, University of California San Diego, La Jolla, California, USA; Rebecca and John Moore Comprehensive Cancer Center, University of California San Diego, La Jolla, California, USA; Veterans Affairs Medical Center, La Jolla, California, USA.
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8
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Ear J, Ali Abd El-hafeez A, Roy S, Ngo T, Rajapakse N, Choi J, Khandelwal S, Ghassemian M, Mccaffrey L, Kufareva I, Sahoo D, Ghosh P. Evolution of Modularity, Interactome and Functions of GIV/Girdin (CCDC88A) from Invertebrates to Vertebrates.. [DOI: 10.1101/2020.09.28.317172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
AbstractPDZ domains are one of the most abundant protein domains in eukaryotes and frequently found on junction-localized scaffold proteins. Various signaling molecules bind to PDZ proteins via PDZ-binding motifs (PBM) and finetune cellular signaling. Here we describe the presence of a PBM on GIV/Girdin (CCDC88A) that is conserved throughout evolution, from invertebrates to vertebrates, and is generated as a long isoform-variant in humans, which we named GIV-L. Unlike GIV, which lacks PBM and is cytosolic, GIV-L localizes to the cell junctions, and has a unique PDZ-interactome, which impacts GIV-L’s ability to bind and activate trimeric G-protein, Gi through its guanine-nucleotide exchange modulator (GEM) module; the GEM module is found exclusively in vertebrates. Thus, the two functional modules in GIV evolved sequentially: the ability to bind PDZ proteins via the PBM evolved earlier in invertebrates, whereas G-protein binding and activation may have evolved later only among vertebrates. Phenotypic studies in Caco-2 cells revealed that GIV and GIV-L may have antagonistic effects on cell growth, proliferation (cell cycle), and survival. Immunohistochemical analyses in human colon tissues showed that GIV expression increases with a concomitant decrease in GIV-L during cancer initiation. Taken together, these findings reveal how GIV/CCDC88A in humans displays evolutionary flexibility in modularity, which allows the resultant isoforms to play opposing roles either as a tumor suppressor (GIV-L) or as an oncogene (GIV).
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Marivin A, Maziarz M, Zhao J, DiGiacomo V, Calvo IO, Mann EA, Ear J, Blanco-Canosa JB, Ross EM, Ghosh P, Garcia-Marcos M. Correction: DAPLE protein inhibits nucleotide exchange on Gαs and Gαq via the same motif that activates Gαi. J Biol Chem 2020; 295:8867. [DOI: 10.1074/jbc.aac120.014344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Ear J, Saklecha A, Rajapakse N, Choi J, Ghassemian M, Kufareva I, Ghosh P. Tyrosine‐based Signals Converge on Daple&[bull]PARD3 Complex to Fine‐tune Polarized Planar Cell Migration. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.08628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Marivin A, Maziarz M, Zhao J, DiGiacomo V, Olmos Calvo I, Mann EA, Ear J, Blanco-Canosa JB, Ross EM, Ghosh P, Garcia-Marcos M. DAPLE protein inhibits nucleotide exchange on Gα s and Gα q via the same motif that activates Gαi. J Biol Chem 2020; 295:2270-2284. [PMID: 31949046 DOI: 10.1074/jbc.ra119.011648] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/08/2020] [Indexed: 01/03/2023] Open
Abstract
Besides being regulated by G-protein-coupled receptors, the activity of heterotrimeric G proteins is modulated by many cytoplasmic proteins. GIV/Girdin and DAPLE (Dvl-associating protein with a high frequency of leucine) are the best-characterized members of a group of cytoplasmic regulators that contain a Gα-binding and -activating (GBA) motif and whose dysregulation underlies human diseases, including cancer and birth defects. GBA motif-containing proteins were originally reported to modulate G proteins by binding Gα subunits of the Gi/o family (Gαi) over other families (such as Gs, Gq/11, or G12/13), and promoting nucleotide exchange in vitro However, some evidence suggests that this is not always the case, as phosphorylation of the GBA motif of GIV promotes its binding to Gαs and inhibits nucleotide exchange. The G-protein specificity of DAPLE and how it might affect nucleotide exchange on G proteins besides Gαi remain to be investigated. Here, we show that DAPLE's GBA motif, in addition to Gαi, binds efficiently to members of the Gs and Gq/11 families (Gαs and Gαq, respectively), but not of the G12/13 family (Gα12) in the absence of post-translational phosphorylation. We pinpointed Met-1669 as the residue in the GBA motif of DAPLE that diverges from that in GIV and enables better binding to Gαs and Gαq Unlike the nucleotide-exchange acceleration observed for Gαi, DAPLE inhibited nucleotide exchange on Gαs and Gαq These findings indicate that GBA motifs have versatility in their G-protein-modulating effect, i.e. they can bind to Gα subunits of different classes and either stimulate or inhibit nucleotide exchange depending on the G-protein subtype.
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Affiliation(s)
- Arthur Marivin
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Marcin Maziarz
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Jingyi Zhao
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Vincent DiGiacomo
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Isabel Olmos Calvo
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Emily A Mann
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Jason Ear
- Department of Medicine and Cellular and Molecular Medicine, University of California, San Diego, California 92093
| | - Juan B Blanco-Canosa
- Department of Biological Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona, Spain 08034
| | - Elliott M Ross
- Department of Pharmacology, Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Pradipta Ghosh
- Department of Medicine and Cellular and Molecular Medicine, University of California, San Diego, California 92093
| | - Mikel Garcia-Marcos
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118.
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12
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Ear J, Dunkel Y, Mittal Y, Lim BBC, Liu L, Holda MK, Nitsche U, Barbazán J, Goel A, Janssen KP, Aznar N, Ghosh P. Two Isoforms of the Guanine Nucleotide Exchange Factor, Daple/CCDC88C Cooperate as Tumor Suppressors. Sci Rep 2019; 9:12124. [PMID: 31431650 PMCID: PMC6702192 DOI: 10.1038/s41598-019-48420-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 08/01/2019] [Indexed: 01/27/2023] Open
Abstract
Previously, Aznar et al., showed that Daple/CCDC88C enables Wnt receptors to transactivate trimeric G-proteins during non-canonical Wnt signaling via a novel G-protein binding and activating (GBA) motif. By doing so, Daple serves two opposing roles; earlier during oncogenesis it suppresses neoplastic transformation and tumor growth, but later it triggers epithelial-to-mesenchymal-transition (EMT). We have identified and characterized two isoforms of the human Daple gene. While both isoforms cooperatively suppress tumor growth via their GBA motif, only the full-length transcript triggers EMT and invasion. Both isoforms are suppressed during colon cancer progression, and their reduced expression carries additive prognostic significance. These findings provide insights into the opposing roles of Daple during cancer progression and define the G-protein regulatory GBA motif as one of the minimal modules essential for Daple’s role as a tumor suppressor.
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Affiliation(s)
- Jason Ear
- Department of Medicine, University of California, San Diego, La Jolla, California, USA.,Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
| | - Ying Dunkel
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Yash Mittal
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Blaze B C Lim
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Lawrence Liu
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Magda K Holda
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Ulrich Nitsche
- Department of Surgery, Klinikumrechts der Isar, TechnischeUniversitätMünchen, Munich, Germany
| | - Jorge Barbazán
- Translational Medical Oncology Laboratory, Health Research Institute of Santiago (IDIS), SERGAS., Santiago de Compostela, Spain
| | - Ajay Goel
- Division of Gastroenterology, Department of Internal Medicine and Charles A. Sammons Cancer Center and Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
| | - Klaus-Peter Janssen
- Department of Surgery, Klinikumrechts der Isar, TechnischeUniversitätMünchen, Munich, Germany
| | - Nicolas Aznar
- Department of Medicine, University of California, San Diego, La Jolla, California, USA. .,Cancer Research Center of Lyon, Centre Léon Bérard, Lyon, France.
| | - Pradipta Ghosh
- Department of Medicine, University of California, San Diego, La Jolla, California, USA. .,Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA. .,Moores Cancer Center, University of California, San Diego, La Jolla, California, USA.
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13
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Dunkel Y, Reid AL, Ear J, Aznar N, Millward M, Gray E, Pearce R, Ziman M, Ghosh P. Prognostic Relevance of CCDC88C (Daple) Transcripts in the Peripheral Blood of Patients with Cutaneous Melanoma. Sci Rep 2018; 8:18036. [PMID: 30575751 PMCID: PMC6303298 DOI: 10.1038/s41598-018-36173-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 11/15/2018] [Indexed: 01/12/2023] Open
Abstract
A loss of balance between G protein activation and deactivation has been implicated in the initiation of melanomas, and non-canonical Wnt signaling via the Wnt5A/Frizzled (FZD) pathway has been shown to be critical for the switch to an invasive phenotype. Daple [CCDC88C], a cytosolic guanine nucleotide exchange modulator (GEM) which enhances non-canonical Wnt5A/FZD signaling via activation of trimeric G protein, Gαi, has been shown to serve opposing roles-as an inducer of EMT and invasiveness and a potent tumor suppressor-via two isoforms, V1 (full-length) and V2 (short spliced isoform), respectively. Here we report that the relative abundance of these isoforms in the peripheral circulation, presumably largely from circulating tumor cells (CTCs), is a prognostic marker of cutaneous melanomas. Expression of V1 is increased in both the early and late clinical stages (p < 0.001, p = 0.002, respectively); V2 is decreased exclusively in the late clinical stage (p = 0.003). The two isoforms have opposing prognostic effects: high expression of V2 increases relapse-free survival (RFS; p = 0.014), whereas high expression of V1 tends to decrease RFS (p = 0.051). Furthermore, these effects are additive, in that melanoma patients with a low V2-high V1 signature carry the highest risk of metastatic disease. We conclude that detection of Daple transcripts in the peripheral blood (i.e., liquid biopsies) of patients with melanoma may serve as a prognostic marker and an effective strategy for non-invasive long-term follow-up of patients with melanoma.
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Affiliation(s)
- Ying Dunkel
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Anna L Reid
- School of Medical Sciences, Edith Cowan University, Perth, WA, Australia
| | - Jason Ear
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Nicolas Aznar
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
- Centre de Recherche enCancérologie de Lyon (CRCL), Lyon, France
| | - Michael Millward
- School of Medicine, University of Western Australia, Crawley, Australia
- Department of Medical Oncology, Sir Charles Gairdner Hospital, Nedlands, Australia
| | - Elin Gray
- School of Medical Sciences, Edith Cowan University, Perth, WA, Australia
| | - Robert Pearce
- School of Medical Sciences, Edith Cowan University, Perth, WA, Australia
| | - Melanie Ziman
- School of Medical Sciences, Edith Cowan University, Perth, WA, Australia.
- School of Biomedical Science, University of Western Australia, Crawley, Australia.
| | - Pradipta Ghosh
- Department of Medicine, University of California, San Diego, La Jolla, California, USA.
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA.
- Rebecca and John Moores Cancer Center, University of California, San Diego, La Jolla, California, USA.
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14
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Ear J, Aznar N, Dunkel Y, Sun N, Satterfield K, He F, Lopez‐Sanchez I, Ghassemian M, Sahoo D, Kufareva I, Ghosh P. Convergence of Wnt, Growth Factor and Trimeric G‐protein Signals on the Signaling Scaffold Daple. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.533.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jason Ear
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | - Nicolas Aznar
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | - Ying Dunkel
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | - Nina Sun
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | - Kendall Satterfield
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | - Fang He
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | | | - Majid Ghassemian
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | - Debashis Sahoo
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | - Irina Kufareva
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
| | - Pradipta Ghosh
- Cellular and Molecular MedicineUniversity of California San DiegoSan DiegoCA
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15
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Aznar N, Ear J, Dunkel Y, Sun N, Satterfield K, He F, Kalogriopoulos NA, Lopez-Sanchez I, Ghassemian M, Sahoo D, Kufareva I, Ghosh P. Convergence of Wnt, growth factor, and heterotrimeric G protein signals on the guanine nucleotide exchange factor Daple. Sci Signal 2018; 11:11/519/eaao4220. [PMID: 29487190 DOI: 10.1126/scisignal.aao4220] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cellular proliferation, differentiation, and morphogenesis are shaped by multiple signaling cascades, and their dysregulation plays an integral role in cancer progression. Three cascades that contribute to oncogenic potential are those mediated by Wnt proteins and the receptor Frizzled (FZD), growth factor receptor tyrosine kinases (RTKs), and heterotrimeric G proteins and associated GPCRs. Daple is a guanine nucleotide exchange factor (GEF) for the G protein Gαi Daple also binds to FZD and the Wnt/FZD mediator Dishevelled (Dvl), and it enhances β-catenin-independent Wnt signaling in response to Wnt5a-FZD7 signaling. We identified Daple as a substrate of multiple RTKs and non-RTKs and, hence, as a point of convergence for the three cascades. We found that phosphorylation near the Dvl-binding motif in Daple by both RTKs and non-RTKs caused Daple/Dvl complex dissociation and augmented the ability of Daple to bind to and activate Gαi, which potentiated β-catenin-independent Wnt signals and stimulated epithelial-mesenchymal transition (EMT) similarly to Wnt5a/FZD7 signaling. Although Daple acts as a tumor suppressor in the healthy colon, the concurrent increased abundance of Daple and epidermal growth factor receptor (EGFR) in colorectal tumors was associated with poor patient prognosis. Thus, the Daple-dependent activation of Gαi and the Daple-dependent enhancement of β-catenin-independent Wnt signals are not only stimulated by Wnt5a/FZD7 to suppress tumorigenesis but also hijacked by growth factor-activated RTKs to enhance tumor progression. These findings identify a cross-talk paradigm among growth factor RTKs, heterotrimeric G proteins, and the Wnt/FZD pathway in cancer.
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Affiliation(s)
- Nicolas Aznar
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Jason Ear
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Ying Dunkel
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Nina Sun
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kendall Satterfield
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Fang He
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | | | | | - Majid Ghassemian
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA
| | - Debashis Sahoo
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA.,Department of Computer Science and Engineering, Jacobs School of Engineering, University of California, San Diego, La Jolla, CA 92093, USA
| | - Irina Kufareva
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Pradipta Ghosh
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA. .,Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA.,Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
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16
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Aznar N, Sun N, Dunkel Y, Ear J, Buschman MD, Ghosh P. A Daple-Akt feed-forward loop enhances noncanonical Wnt signals by compartmentalizing β-catenin. Mol Biol Cell 2017; 28:3709-3723. [PMID: 29021338 PMCID: PMC5706997 DOI: 10.1091/mbc.e17-06-0405] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/04/2017] [Accepted: 10/06/2017] [Indexed: 01/12/2023] Open
Abstract
Balance between canonical and noncanonical Wnt pathways controls the β-catenin transcriptional program; how the noncanonical pathway antagonizes the canonical pathway remains unclear. We show that Daple, an enhancer of noncanonical Wnt signals, accomplishes that goal by dictating the subcellular distribution of β-catenin in cells. Cellular proliferation is antagonistically regulated by canonical and noncanonical Wnt signals; their dysbalance triggers cancers. We previously showed that a multimodular signal transducer, Daple, enhances PI3-K→Akt signals within the noncanonical Wnt signaling pathway and antagonistically inhibits canonical Wnt responses. Here we demonstrate that the PI3-K→Akt pathway serves as a positive feedback loop that further enhances noncanonical Wnt signals by compartmentalizing β-catenin. By phosphorylating the phosphoinositide- (PI) binding domain of Daple, Akt abolishes Daple’s ability to bind PI3-P-enriched endosomes that engage dynein motor complex for long-distance trafficking of β-catenin/E-cadherin complexes to pericentriolar recycling endosomes (PCREs). Phosphorylation compartmentalizes Daple/β-catenin/E-cadherin complexes to cell–cell contact sites, enhances noncanonical Wnt signals, and thereby suppresses colony growth. Dephosphorylation compartmentalizes β-catenin on PCREs, a specialized compartment for prolonged unopposed canonical Wnt signaling, and enhances colony growth. Cancer-associated Daple mutants that are insensitive to Akt mimic a constitutively dephosphorylated state. This work not only identifies Daple as a platform for cross-talk between Akt and the noncanonical Wnt pathway but also reveals the impact of such cross-talk on tumor cell phenotypes that are critical for cancer initiation and progression.
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Affiliation(s)
- Nicolas Aznar
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Nina Sun
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Ying Dunkel
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Jason Ear
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Matthew D Buschman
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Pradipta Ghosh
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093 .,Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Moores Cancer Centre, University of California, San Diego, La Jolla, CA 92093
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17
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Ghosh P, Aznar N, Swanson L, Lo IC, Lopez-Sanchez I, Ear J, Rohena C, Kalogriopoulos N, Joosen L, Dunkel Y, Sun N, Nguyen P, Bhandari D. Biochemical, Biophysical and Cellular Techniques to Study the Guanine Nucleotide Exchange Factor, GIV/Girdin. Curr Protoc Chem Biol 2016; 8:265-298. [PMID: 27925669 PMCID: PMC5154557 DOI: 10.1002/cpch.13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Canonical signal transduction via heterotrimeric G proteins is spatiotemporally restricted, i.e., triggered exclusively at the plasma membrane, only by agonist activation of G protein-coupled receptors via a finite process that is terminated within a few hundred milliseconds. Recently, a rapidly emerging paradigm has revealed a noncanonical pathway for activation of heterotrimeric G proteins via the nonreceptor guanidine-nucleotide exchange factor, GIV/Girdin. Biochemical, biophysical, and functional studies evaluating this pathway have unraveled its unique properties and distinctive spatiotemporal features. As in the case of any new pathway/paradigm, these studies first required an in-depth optimization of tools/techniques and protocols, governed by rationale and fundamentals unique to the pathway, and more specifically to the large multimodular GIV protein. Here we provide the most up-to-date overview of protocols that have generated most of what we know today about noncanonical G protein activation by GIV and its relevance in health and disease. © 2016 by John Wiley & Sons, Inc.
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Affiliation(s)
- Pradipta Ghosh
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093-0651
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | - Nicolas Aznar
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | - Lee Swanson
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | - I-Chung Lo
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | | | - Jason Ear
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | - Cristina Rohena
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | | | - Linda Joosen
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | - Ying Dunkel
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | - Nina Sun
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0651
| | - Peter Nguyen
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840-9507
| | - Deepali Bhandari
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840-9507
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18
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Lin C, Ear J, Midde K, Lopez-Sanchez I, Aznar N, Garcia-Marcos M, Kufareva I, Abagyan R, Ghosh P. Structural basis for activation of trimeric Gi proteins by multiple growth factor receptors via GIV/Girdin. Mol Biol Cell 2014; 25:3654-71. [PMID: 25187647 PMCID: PMC4230624 DOI: 10.1091/mbc.e14-05-0978] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
GIV, a guanidine exchange factor for trimeric Gi, contains a unique domain that functions like a SH2 domain. GIV's SH2-like domain binds autophosphorylated RTKs. Binding of GIV's SH2 to RTKs enables the receptors to activate trimeric Gi. Inhibition of GIV:RTK interaction abolishes GIV-dependent Akt enhancement downstream of RTKs. A long-standing issue in the field of signal transduction is to understand the cross-talk between receptor tyrosine kinases (RTKs) and heterotrimeric G proteins, two major and distinct signaling hubs that control eukaryotic cell behavior. Although stimulation of many RTKs leads to activation of trimeric G proteins, the molecular mechanisms behind this phenomenon remain elusive. We discovered a unifying mechanism that allows GIV/Girdin, a bona fide metastasis-related protein and a guanine-nucleotide exchange factor (GEF) for Gαi, to serve as a direct platform for multiple RTKs to activate Gαi proteins. Using a combination of homology modeling, protein–protein interaction, and kinase assays, we demonstrate that a stretch of ∼110 amino acids within GIV C-terminus displays structural plasticity that allows folding into a SH2-like domain in the presence of phosphotyrosine ligands. Using protein–protein interaction assays, we demonstrated that both SH2 and GEF domains of GIV are required for the formation of a ligand-activated ternary complex between GIV, Gαi, and growth factor receptors and for activation of Gαi after growth factor stimulation. Expression of a SH2-deficient GIV mutant (Arg 1745→Leu) that cannot bind RTKs impaired all previously demonstrated functions of GIV—Akt enhancement, actin remodeling, and cell migration. The mechanistic and structural insights gained here shed light on the long-standing questions surrounding RTK/G protein cross-talk, set a novel paradigm, and characterize a unique pharmacological target for uncoupling GIV-dependent signaling downstream of multiple oncogenic RTKs.
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Affiliation(s)
- Changsheng Lin
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| | - Jason Ear
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| | - Krishna Midde
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| | | | - Nicolas Aznar
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| | - Mikel Garcia-Marcos
- Department of Cellular and Molecular Medicine, University of California, San Diego, School of Medicine, CA 92093
| | - Irina Kufareva
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Ruben Abagyan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Pradipta Ghosh
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
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Lin S, Zhao Y, Ji Z, Ear J, Chang CH, Zhang H, Low-Kam C, Yamada K, Meng H, Wang X, Liu R, Pokhrel S, Mädler L, Damoiseaux R, Xia T, Godwin HA, Lin S, Nel AE. Zebrafish high-throughput screening to study the impact of dissolvable metal oxide nanoparticles on the hatching enzyme, ZHE1. Small 2013; 9:1776-1785. [PMID: 23180726 PMCID: PMC4034474 DOI: 10.1002/smll.201202128] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Indexed: 05/19/2023]
Abstract
The zebrafish is emerging as a model organism for the safety assessment and hazard ranking of engineered nanomaterials. In this Communication, the implementation of a roboticized high-throughput screening (HTS) platform with automated image analysis is demonstrated to assess the impact of dissolvable oxide nanoparticles on embryo hatching. It is further demonstrated that this hatching interference is mechanistically linked to an effect on the metalloprotease, ZHE 1, which is responsible for degradation of the chorionic membrane. The data indicate that 4 of 24 metal oxide nanoparticles (CuO, ZnO, Cr2 O3 , and NiO) could interfere with embryo hatching by a chelator-sensitive mechanism that involves ligation of critical histidines in the ZHE1 center by the shed metal ions. A recombinant ZHE1 enzymatic assay is established to demonstrate that the dialysates from the same materials responsible for hatching interference also inhibit ZHE1 activity in a dose-dependent fashion. A peptide-based BLAST search identifies several additional aquatic species that express enzymes with homologous histidine-based catalytic centers, suggesting that the ZHE1 mechanistic paradigm could be used to predict the toxicity of a large number of oxide nanoparticles that pose a hazard to aquatic species.
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Affiliation(s)
- Sijie Lin
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
| | - Yan Zhao
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles
| | - Zhaoxia Ji
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
| | - Jason Ear
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles
| | - Chong Hyun Chang
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
| | - Haiyuan Zhang
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
| | - Cecile Low-Kam
- Department of Biostatistics, University of California, Los Angeles
| | - Kristin Yamada
- Department of Environmental Health Sciences, University of California, Los Angeles
| | - Huan Meng
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
- Division of NanoMedicine, Department of Medicine, University of California, Los Angeles
| | - Xiang Wang
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
| | - Rong Liu
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
| | - Suman Pokhrel
- IWT Foundation Institute of Materials Science, Department of Production Engineering, University of Bremen, Germany
| | - Lutz Mädler
- IWT Foundation Institute of Materials Science, Department of Production Engineering, University of Bremen, Germany
| | - Robert Damoiseaux
- Molecular Shared Screening Resources, California NanoSystem Institute, University of California, Los Angeles
| | - Tian Xia
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
- Division of NanoMedicine, Department of Medicine, University of California, Los Angeles
| | - Hilary A. Godwin
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
- Department of Environmental Health Sciences, University of California, Los Angeles
| | - Shuo Lin
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles
| | - André E. Nel
- Center for Environmental Implications of Nanotechnology, University of California, Los Angeles
- Division of NanoMedicine, Department of Medicine, University of California, Los Angeles
- Prof. A. E. Nel, Department of Medicine, Division of NanoMedicine, UCLA School of Medicine, 52-175, CHS, 10833 Le Conte Ave, Los Angeles, CA 90095-1680. Tel: (310) 825-6620, Fax: (310) 206-8107,
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Stafford RL, Hinde E, Knight MJ, Pennella MA, Ear J, Digman MA, Gratton E, Bowie JU. Tandem SAM domain structure of human Caskin1: a presynaptic, self-assembling scaffold for CASK. Structure 2012; 19:1826-36. [PMID: 22153505 DOI: 10.1016/j.str.2011.09.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 08/30/2011] [Accepted: 09/18/2011] [Indexed: 01/22/2023]
Abstract
The synaptic scaffolding proteins CASK and Caskin1 are part of the fibrous mesh of proteins that organize the active zones of neural synapses. CASK binds to a region of Caskin1 called the CASK interaction domain (CID). Adjacent to the CID, Caskin1 contains two tandem sterile α motif (SAM) domains. Many SAM domains form polymers so they are good candidates for forming the fibrous structures seen in the active zone. We show here that the SAM domains of Caskin1 form a new type of SAM helical polymer. The Caskin1 polymer interface exhibits a remarkable segregation of charged residues, resulting in a high sensitivity to ionic strength in vitro. The Caskin1 polymers can be decorated with CASK proteins, illustrating how these proteins may work together to organize the cytomatrix in active zones.
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Affiliation(s)
- Ryan L Stafford
- Department of Chemistry and Biochemistry, UCLA-DOE Institute of Genomics and Proteomics, Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095-1570, USA
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Lin C, Ear J, Pavlova Y, Mittal Y, Kufareva I, Ghassemian M, Abagyan R, Garcia-Marcos M, Ghosh P. Tyrosine phosphorylation of the Gα-interacting protein GIV promotes activation of phosphoinositide 3-kinase during cell migration. Sci Signal 2012; 4:ra64. [PMID: 21954290 DOI: 10.1126/scisignal.2002049] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
GIV (Gα-interacting vesicle-associated protein; also known as Girdin) enhances Akt activation downstream of multiple growth factor- and G protein (heterotrimeric guanosine 5'-triphosphate-binding protein)-coupled receptors to trigger cell migration and cancer invasion. We demonstrate that GIV is a tyrosine phosphoprotein that directly binds to and activates phosphoinositide 3-kinase (PI3K). Upon ligand stimulation of various receptors, GIV was phosphorylated at tyrosine-1764 and tyrosine-1798 by both receptor and non-receptor tyrosine kinases. These phosphorylation events enabled direct binding of GIV to the amino- and carboxyl-terminal Src homology 2 domains of p85α, a regulatory subunit of PI3K; stabilized receptor association with PI3K; and enhanced PI3K activity at the plasma membrane to trigger cell migration. Tyrosine phosphorylation of GIV and its association with p85α increased during metastatic progression of a breast carcinoma. These results suggest a mechanism by which multiple receptors activate PI3K through tyrosine phosphorylation of GIV, thereby making the GIV-PI3K interaction a potential therapeutic target within the PI3K-Akt pathway.
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Affiliation(s)
- Changsheng Lin
- Department of Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093, USA
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Stafford RL, Ear J, Knight MJ, Bowie JU. The molecular basis of the Caskin1 and Mint1 interaction with CASK. J Mol Biol 2011; 412:3-13. [PMID: 21763699 DOI: 10.1016/j.jmb.2011.07.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2011] [Revised: 07/05/2011] [Accepted: 07/05/2011] [Indexed: 12/21/2022]
Abstract
Calcium/calmodulin-dependent serine protein kinase (CASK) is a conserved multi-domain scaffolding protein involved in brain development, synapse formation, and establishment of cell polarity. To accomplish these diverse functions, CASK participates in numerous protein-protein interactions. In particular, CASK forms competing CASK/Mint1/Velis and CASK/Caskin1/Velis tripartite complexes that physically associate with the cytoplasmic tail of neurexin, a transmembrane protein enriched at presynaptic sites. This study shows that a short linear EEIWVLRK peptide motif from Caskin1 is necessary and sufficient for binding CASK. We also identified the conserved binding site for the peptide on the CASK calmodulin kinase domain. A related EPIWVMRQ peptide from Mint1 was also discovered to be sufficient for binding. Searching all human proteins for the Mint1/Caskin1 consensus peptide ExIWVxR revealed that T-cell lymphoma invasion and metastasis 1 (TIAM1) contains a conserved EEVIWVRRE peptide that was also found to be sufficient for CASK binding in vitro. TIAM1 is well known for its role in tumor metastasis, but it also possesses overlapping cellular and neurological functions with CASK, suggesting a previously unknown cooperation between the two proteins. This new peptide interaction motif also explains how Caskin1 and Mint1 form competing complexes and suggests a new role for the cellular hub protein CASK.
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Affiliation(s)
- Ryan L Stafford
- Department of Chemistry and Biochemistry, UCLA-DOE Institute of Genomics and Proteomics, Molecular Biology Institute, University of California, Los Angeles, Boyer Hall, 611 Charles E. Young Drive East, Los Angeles, CA 90095-1570, USA
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Garcia-Marcos M, Ear J, Farquhar MG, Ghosh P. A GDI (AGS3) and a GEF (GIV) regulate autophagy by balancing G protein activity and growth factor signals. Mol Biol Cell 2011; 22:673-86. [PMID: 21209316 PMCID: PMC3046063 DOI: 10.1091/mbc.e10-08-0738] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
This work introduces a nonreceptor GEF for Gαi subunits as a regulator of autophagy. The authors reveal how growth factors reversibly regulate autophagy by a unique mechanism that involves reversible regulation of Gαi3 activity by AGS3, a GDI, and GIV, a GEF, during initiation and reversal of autophagy, respectively. Autophagy is the major catabolic process responsible for the removal of aggregated proteins and damaged organelles. Autophagy is regulated by both G proteins and growth factors, but the underlying mechanism of how they are coordinated during initiation and reversal of autophagy is unknown. Using protein–protein interaction assays, G protein enzymology, and morphological analysis, we demonstrate here that Gα-interacting, vesicle-associated protein (GIV, a. k. a. Girdin), a nonreceptor guanine nucleotide exchange factor for Gαi3, plays a key role in regulating autophagy and that dynamic interplay between Gαi3, activator of G-protein signaling 3 (AGS3, its guanine nucleotide dissociation inhibitor), and GIV determines whether autophagy is promoted or inhibited. We found that AGS3 directly binds light chain 3 (LC3), recruits Gαi3 to LC3-positive membranes upon starvation, and promotes autophagy by inhibiting the G protein. Upon growth factor stimulation, GIV disrupts the Gαi3–AGS3 complex, releases Gαi3 from LC3-positive membranes, enhances anti-autophagic signaling pathways, and inhibits autophagy by activating the G protein. These results provide mechanistic insights into how reversible modulation of Gαi3 activity by AGS3 and GIV maintains the delicate equilibrium between promotion and inhibition of autophagy.
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Affiliation(s)
- Mikel Garcia-Marcos
- Departments of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093 , USA.
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Garcia-Marcos M, Jung BH, Ear J, Cabrera B, Carethers JM, Ghosh P. Expression of GIV/Girdin, a metastasis-related protein, predicts patient survival in colon cancer. FASEB J 2010; 25:590-9. [PMID: 20974669 DOI: 10.1096/fj.10-167304] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Metastasis accounts for the majority of cancer-related deaths. Accurate prediction of metastatic potential of tumors has been elusive, and the search for clinically useful markers continues. We previously reported that GIV/Girdin triggers tumor cell migration by virtue of a C-terminal guanine-nucleotide exchange factor motif that activates Gαi. Here we identify GIV as a metastasis-related protein whose full-length transcript (GIV-fl) is expressed exclusively in highly invasive colon, breast, and pancreatic carcinoma cells and not in their poorly invasive counterparts. A prospective, exploratory biomarker study conducted on a cohort of 56 patients with stage II colorectal cancer revealed a significant correlation between GIV-fl expression in tumor epithelium and shortened metastasis-free survival. Survival rate for patients with GIV-fl-positive tumors is significantly reduced compared with the patients with GIV-fl-negative tumors [P<0.0001; hazard ratio=0.076; CI=0.052-0.30 (95%)]. At the 5-yr mark, survival is 100% in the GIV-fl-negative group and 62 ± 9% (mean±SE; P=6×10(-5)) in the GIV-fl-positive group. Furthermore, GIV-fl expression predicts a risk of mortality independent of the microsatellite stability status, a well-established prognosticator of colorectal cancers. We conclude that GIV-fl is a novel metastasis-related protein and an independent adverse prognosticator that may serve as a useful adjunct to traditional staging strategies in colorectal carcinoma.
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Affiliation(s)
- Mikel Garcia-Marcos
- Department of Cellular and Molecular Medicine, George E. Palade Laboratories, University of California, San Diego School of Medicine, La Jolla, CA 92093-0651, USA
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Ghosh P, Beas AO, Bornheimer SJ, Garcia-Marcos M, Forry EP, Johannson C, Ear J, Jung BH, Cabrera B, Carethers JM, Farquhar MG. A G{alpha}i-GIV molecular complex binds epidermal growth factor receptor and determines whether cells migrate or proliferate. Mol Biol Cell 2010; 21:2338-54. [PMID: 20462955 PMCID: PMC2893996 DOI: 10.1091/mbc.e10-01-0028] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Migrating cells do not proliferate and vice versa, but the mechanism involved remains unknown. Ghosh et al. reveal how this cellular decision is made by showing that a Gαi–GIV molecular complex interacts with EGF receptor and programs growth factor signaling, triggering migration when assembled and favoring mitosis when assembly is prevented. Cells respond to growth factors by either migrating or proliferating, but not both at the same time, a phenomenon termed migration-proliferation dichotomy. The underlying mechanism of this phenomenon has remained unknown. We demonstrate here that Gαi protein and GIV, its nonreceptor guanine nucleotide exchange factor (GEF), program EGF receptor (EGFR) signaling and orchestrate this dichotomy. GIV directly interacts with EGFR, and when its GEF function is intact, a Gαi–GIV–EGFR signaling complex assembles, EGFR autophosphorylation is enhanced, and the receptor's association with the plasma membrane (PM) is prolonged. Accordingly, PM-based motogenic signals (PI3-kinase-Akt and PLCγ1) are amplified, and cell migration is triggered. In cells expressing a GEF-deficient mutant, the Gαi–GIV-EGFR signaling complex is not assembled, EGFR autophosphorylation is reduced, the receptor's association with endosomes is prolonged, mitogenic signals (ERK 1/2, Src, and STAT5) are amplified, and cell proliferation is triggered. In rapidly growing, poorly motile breast and colon cancer cells and in noninvasive colorectal carcinomas in situ in which EGFR signaling favors mitosis over motility, a GEF-deficient splice variant of GIV was identified. In slow growing, highly motile cancer cells and late invasive carcinomas, GIV is highly expressed and has an intact GEF motif. Thus, inclusion or exclusion of GIV's GEF motif, which activates Gαi, modulates EGFR signaling, generates migration-proliferation dichotomy, and most likely influences cancer progression.
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Affiliation(s)
- Pradipta Ghosh
- Department of Cellular and Molecular Medicine and Medicine, School of Medicine, University of California-San Diego, La Jolla, CA 92093, USA.
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Garcia‐Marcos M, Ghosh P, Ear J, Farquhar MG. Characterization of GIV‐Gαi3, a Non‐Receptor GEF‐G protein complex involved in cell migration and metastasis. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.856.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Jason Ear
- University of California, San DiegoLa JollaCA
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Garcia-Marcos M, Ghosh P, Ear J, Farquhar MG. A structural determinant that renders G alpha(i) sensitive to activation by GIV/girdin is required to promote cell migration. J Biol Chem 2010; 285:12765-77. [PMID: 20157114 DOI: 10.1074/jbc.m109.045161] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although several non-receptor activators of heterotrimeric G proteins have been identified, the structural features of G proteins that determine their interaction with such activators and the subsequent biological effects are poorly understood. Here we investigated the structural determinants in G alpha(i3) necessary for its regulation by GIV/girdin, a guanine-nucleotide exchange factor (GEF) that activates G alpha(i) subunits. Using G protein activity and in vitro pulldown assays we demonstrate that G alpha(i3) is a better substrate for GIV than the highly homologous G alpha(o). We identified Trp-258 in the G alpha(i) subunit as a novel structural determinant for GIV binding by comparing GIV binding to G alpha(i3)/G alpha(o) chimeras. Mutation of Trp-258 to the corresponding Phe in G alpha(o) decreased GIV binding in vitro and in cultured cells but did not perturb interaction with other G alpha-binding partners, i.e. G betagamma, AGS3 (a guanine nucleotide dissociation inhibitor), GAIP/RGS19 (a GTPase-activating protein), and LPAR1 (a G protein-coupled receptor). Activation of G alpha(i3) by GIV was also dramatically reduced when Trp-258 was replaced with Tyr, Leu, Ser, His, Asp, or Ala, highlighting that Trp is required for maximal activation. Moreover, when mutant G alpha(i3) W258F was expressed in HeLa cells they failed to undergo cell migration and to enhance Akt signaling after growth factor or G protein-coupled receptor stimulation. Thus activation of G alpha(i3) by GIV is essential for biological functions associated with G alpha(i3) activation. In conclusion, we have discovered a novel structural determinant on G alpha(i) that plays a key role in defining the selectivity and efficiency of the GEF activity of GIV on G alpha(i) and that represents an attractive target site for designing small molecules to disrupt the G alpha(i)-GIV interface for therapeutic purposes.
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Affiliation(s)
- Mikel Garcia-Marcos
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California 92093, USA
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Garcia‐Marcos M, Ghosh P, Ear J, Farquhar MG. GIV is a Non‐Receptor GEF for Gαi with a Unique Motif that Regulates Akt Signaling. FASEB J 2009. [DOI: 10.1096/fasebj.23.1_supplement.879.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mikel Garcia‐Marcos
- Cellular and Molecular MedicineUniversity of CalifarniaSan Diego, La JollaCA
| | - Pradipta Ghosh
- Cellular and Molecular MedicineUniversity of CalifarniaSan Diego, La JollaCA
- MedicineUniversity of CaliforniaSan Diego, La JollaCA
| | - Jason Ear
- Cellular and Molecular MedicineUniversity of CalifarniaSan Diego, La JollaCA
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