1
|
Li M, Zhang L, Zhou P, Zhang Z, Yu R, Zhang Y, Wang Y, Guo H, Pan L, Xiao S, Liu X. Porcine deltacoronavirus nucleocapsid protein interacts with the Grb2 through its proline-rich motifs to induce activation of the Raf-MEK-ERK signal pathway and promote virus replication. J Gen Virol 2024; 105. [PMID: 39136113 DOI: 10.1099/jgv.0.002014] [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] [Indexed: 09/21/2024] Open
Abstract
Porcine deltacoronavirus (PDCoV), an enteropathogenic coronavirus, causes severe watery diarrhoea, dehydration and high mortality in piglets, which has the potential for cross-species transmission in recent years. Growth factor receptor-bound protein 2 (Grb2) is a bridging protein that can couple cell surface receptors with intracellular signal transduction events. Here, we investigated the reciprocal regulation between Grb2 and PDCoV. It is found that Grb2 regulates PDCoV infection and promotes IFN-β production through activating Raf/MEK/ERK/STAT3 pathway signalling in PDCoV-infected swine testis cells to suppress viral replication. PDCoV N is capable of interacting with Grb2. The proline-rich motifs in the N- or C-terminal region of PDCoV N were critical for the interaction between PDCoV-N and Grb2. Except for Deltacoronavirus PDCoV N, the Alphacoronavirus PEDV N protein could interact with Grb2 and affect the regulation of PEDV replication, while the N protein of Betacoronavirus PHEV and Gammacoronavirus AIBV could not interact with Grb2. PDCoV N promotes Grb2 degradation by K48- and K63-linked ubiquitin-proteasome pathways. Overexpression of PDCoV N impaired the Grb2-mediated activated effect on the Raf/MEK/ERK/STAT3 signal pathway. Thus, our study reveals a novel mechanism of how host protein Grb2 protein regulates viral replication and how PDCoV N escaped natural immunity by interacting with Grb2.
Collapse
Affiliation(s)
- Mingxia Li
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Liping Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| | - Peng Zhou
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| | - Zhongwang Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| | - Ruiming Yu
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| | - Yongguang Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| | - Yonglu Wang
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| | - Huichen Guo
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| | - Li Pan
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| | - Sa Xiao
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Xinsheng Liu
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, PR China
| |
Collapse
|
2
|
Bowling FZ, Frohman MA, Airola MV. Structure and regulation of human phospholipase D. Adv Biol Regul 2021; 79:100783. [PMID: 33495125 DOI: 10.1016/j.jbior.2020.100783] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 12/22/2020] [Accepted: 12/28/2020] [Indexed: 12/13/2022]
Abstract
Mammalian phospholipase D (PLD) generates phosphatidic acid, a dynamic lipid secondary messenger involved with a broad spectrum of cellular functions including but not limited to metabolism, migration, and exocytosis. As a promising pharmaceutical target, the biochemical properties of PLD have been well characterized. This has led to the recent crystal structures of human PLD1 and PLD2, the development of PLD specific pharmacological inhibitors, and the identification of cellular regulators of PLD. In this review, we discuss the PLD1 and PLD2 structures, PLD inhibition by small molecules, and the regulation of PLD activity by effector proteins and lipids.
Collapse
Affiliation(s)
- Forrest Z Bowling
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA
| | - Michael A Frohman
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, USA
| | - Michael V Airola
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA.
| |
Collapse
|
3
|
Sanches K, Dias RVR, da Silva PH, Fossey MA, Caruso ÍP, de Souza FP, de Oliveira LC, de Melo FA. Grb2 dimer interacts with Coumarin through SH2 domains: A combined experimental and molecular modeling study. Heliyon 2019; 5:e02869. [PMID: 31844748 PMCID: PMC6889026 DOI: 10.1016/j.heliyon.2019.e02869] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 10/19/2019] [Accepted: 11/12/2019] [Indexed: 01/15/2023] Open
Abstract
Grb2 is an important regulator of normal vs. oncogenic cell signaling transduction. It plays a pivotal role on kinase-mediated signaling transduction by linking Receptor Tyrosine kinases to Ras/MAPK pathway which is known to bring oncogenic outcome. Coumarins are phenolic molecules found in several plants and seeds widely studied because of the antibiotic, anti-inflammatory, anticoagulant, vasodilator, and anti-tumor properties. Despite several studies about the anti-tumor properties of Coumarin in vivo and the role of Grb2 in signaling pathways related to cell proliferation, a molecular level investigation of the interaction between Grb2 and Coumarin is still missing. In this study, we performed a combined set of biophysical approaches to get insights on the interaction between Grb2 in a dimer state and Coumarin. Our results showed that Coumarin interacts with Grb2 dimer through its SH2 domain. The interaction is entropically driven, 1:1 molecular ratio and presents equilibrium constant of 105 M-1. In fact, SH2 is a well-known domain and a versatile signaling module for drug targeting which has been reported to bind compounds that block Ras activation in vivo. Despite we don't know the biological role coming from interaction between Grb2-SH2 domain and Coumarin, it is clear that this molecule could work in the same way as a SH2 domain inhibitor in order to block the link of Receptor Tyrosine kinases to Ras/MAPK pathway.
Collapse
Affiliation(s)
- Karoline Sanches
- Department of Physics, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
- Multiuser Center for Biomolecular Innovation (CMIB), Institute of Biosciences, Humanities and Exact Sciences (IBILCE), São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
| | - Raphael Vinicius Rodrigues Dias
- Department of Physics, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
| | - Paulo Henrique da Silva
- Department of Physics, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
| | - Marcelo Andrés Fossey
- Department of Physics, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
- Multiuser Center for Biomolecular Innovation (CMIB), Institute of Biosciences, Humanities and Exact Sciences (IBILCE), São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
| | - Ícaro Putinhon Caruso
- Department of Physics, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
- Multiuser Center for Biomolecular Innovation (CMIB), Institute of Biosciences, Humanities and Exact Sciences (IBILCE), São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
| | - Fátima Pereira de Souza
- Department of Physics, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
- Multiuser Center for Biomolecular Innovation (CMIB), Institute of Biosciences, Humanities and Exact Sciences (IBILCE), São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
| | - Leandro Cristante de Oliveira
- Department of Physics, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
| | - Fernando Alves de Melo
- Department of Physics, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
- Multiuser Center for Biomolecular Innovation (CMIB), Institute of Biosciences, Humanities and Exact Sciences (IBILCE), São Paulo State University “Júlio de Mesquita Filho” (UNESP), São José do Rio Preto, SP, 15054-000, Brazil
| |
Collapse
|
4
|
Tsai JR, Chong IW, Chen YH, Hwang JJ, Yin WH, Chen HL, Chou SH, Chiu CC, Liu PL. Magnolol induces apoptosis via caspase-independent pathways in non-small cell lung cancer cells. Arch Pharm Res 2013; 37:548-57. [DOI: 10.1007/s12272-013-0232-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2013] [Accepted: 08/01/2013] [Indexed: 11/30/2022]
|
5
|
Design, synthesis, and evaluation of fluorescent cell-penetrating peptidic antagonists of Grb2-SH2 for targeting MCF-7 breast cancer cells. Med Chem Res 2013. [DOI: 10.1007/s00044-013-0538-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
6
|
YIN JIKAI, CAI ZHONGLIANG, ZHANG LI, ZHANG JIAN, HE XIANLI, DU XILIN, WANG QING, LU JIANGUO. A recombined fusion protein PTD-Grb2-SH2 inhibits the proliferation of breast cancer cells in vitro. Int J Oncol 2013; 42:1061-9. [DOI: 10.3892/ijo.2013.1768] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Accepted: 12/17/2012] [Indexed: 11/05/2022] Open
|
7
|
Chiou SM, Chiu CH, Yang ST, Yang JS, Huang HY, Kuo CL, Chen PY, Chung JG. Danthron Triggers ROS and Mitochondria-Mediated Apoptotic Death in C6 Rat Glioma Cells Through Caspase Cascades, Apoptosis-Inducing Factor and Endonuclease G Multiple Signaling. Neurochem Res 2012; 37:1790-800. [DOI: 10.1007/s11064-012-0792-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 04/02/2012] [Accepted: 04/27/2012] [Indexed: 02/08/2023]
|
8
|
Triggering apoptotic death of human malignant melanoma a375.s2 cells by bufalin: involvement of caspase cascade-dependent and independent mitochondrial signaling pathways. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:591241. [PMID: 22719785 PMCID: PMC3376545 DOI: 10.1155/2012/591241] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2012] [Accepted: 03/26/2012] [Indexed: 12/18/2022]
Abstract
Bufalin was obtained from the skin and parotid venom glands of toad and has been shown to induce cytotoxic effects in various types of cancer cell lines, but there is no report to show that whether bufalin affects human skin cancer cells. The aim of this investigation was to study the effects of bufalin on human malignant melanoma A375.S2 cells and to elucidate possible mechanisms involved in induction of apoptosis. A375.S2 cells were treated with different concentrations of bufalin for a specific time period and investigated for effects on apoptotic analyses. Our results indicated that cells after exposure to bufalin significantly decreased cell viability, and induced cell morphological changes and chromatin condensation in a concentration-dependent manner. Flow cytometric assays indicated that bufalin promoted ROS productions, loss of mitochondrial membrane potential (ΔΨm), intracellular Ca2+ release, and nitric oxide (NO) formations in A375.S2 cells. Additionally, the apoptotic induction of bufalin on A375.S2 cells resulted from mitochondrial dysfunction-related responses (disruption of the ΔΨm and releases of cytochrome c, AIF, and Endo G), and activations of caspase-3, caspase-8 and caspase-9 expressions. Based on those observations, we suggest that bufalin-triggered apoptosis in A375.S2 cells is correlated with extrinsic- and mitochondria-mediated multiple signal pathways.
Collapse
|
9
|
GRB2 interaction with the ecotropic murine leukemia virus receptor, mCAT-1, controls virus entry and is stimulated by virus binding. J Virol 2011; 86:1421-32. [PMID: 22090132 DOI: 10.1128/jvi.05993-11] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
For retroviruses such as HIV-1 and murine leukemia virus (MLV), active receptor recruitment and trafficking occur during viral entry. However, the underlying mechanisms and cellular factors involved in the process are largely uncharacterized. The viral receptor for ecotropic MLV (eMLV), a classical model for retrovirus infection mechanisms and pathogenesis, is mouse cationic amino acid transporter 1 (mCAT-1). Growth factor receptor-bound protein 2 (GRB2) is an adaptor protein that has been shown to couple cell surface receptors, such as epidermal growth factor receptor (EGFR) and hepatocyte growth factor receptor, to intracellular signaling events. Here we examined if GRB2 could also play a role in controlling infection by retroviruses by affecting receptor function. The GRB2 RNA interference (RNAi)-mediated suppression of endogenous GRB2 resulted in a consistent and significant reduction of virus binding and membrane fusion. The binding between eMLV and cells promoted increased GRB2-mCAT-1 interactions, as detected by immunoprecipitation. Consistently, the increased colocalization of GRB2 and mCAT-1 signals was detected by confocal microscopy. This association was time dependent and paralleled the kinetics of cell-virus membrane fusion. Interestingly, unlike the canonical binding pattern seen for GRB2 and growth factor receptors, GRB2-mCAT-1 binding does not depend on the GRB2-SH2 domain-mediated recognition of tyrosine phosphorylation on the receptor. The inhibition of endogenous GRB2 led to a reduction in surface levels of mCAT-1, which was detected by immunoprecipitation and by a direct binding assay using a recombinant MLV envelope protein receptor binding domain (RBD). Consistent with this observation, the expression of a dominant negative GRB2 mutant (R86K) resulted in the sequestration of mCAT-1 from the cell surface into intracellular vesicles. Taken together, these findings suggest a novel role for GRB2 in ecotropic MLV entry and infection by facilitating mCAT-1 trafficking.
Collapse
|
10
|
Yang SY, Chen Y, Yang CX, Yang DL, Kuo SC, Huang LJ, Lung FDT. Structure-activity relationships of a peptidic antagonist of Id1 studied by biosensor method, circular dichroism spectroscopy, and bioassay. J Pept Sci 2011; 17:667-74. [DOI: 10.1002/psc.1386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 05/16/2011] [Accepted: 05/16/2011] [Indexed: 01/26/2023]
|
11
|
Chen CH, Kuo SC, Huang LJ, Hsu MH, Lung FDT. Affinity of synthetic peptide fragments of MyoD for Id1 protein and their biological effects in several cancer cells. J Pept Sci 2010; 16:231-41. [PMID: 20235117 DOI: 10.1002/psc.1216] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
MyoD is a DNA-binding protein capable of specific interactions that involve the helix-loop-helix (HLH) domain. The HLH motif of MyoD can form oligomers with the HLH motif of Id1 (the inhibitor of DNA-binding proteins) that folds into a highly stable helical conformation stabilized by the self-association. The Id family consists of four related proteins that contain a highly conserved dimerization motif known as the HLH domain. In signaling pathways, Id proteins act as dominant negative antagonists of the basic helix-loop-helix (bHLH) family of transcription factors which play important roles in cellular development, proliferation, and differentiation. The mechanism of Id proteins is to antagonize bHLH proteins by binding as dominant negative HLH proteins to form high-affinity heterodimers with other bHLH proteins, thereby preventing them from binding to DNA and inhibiting transcription of differentiation-associated genes. The goal of this study is to design and synthesize peptide fragments of MyoD with high affinity for Id1 to interrupt the interactions among Id1, MyoD, and other bHLH DNA-binding proteins and to inhibit the proliferation of cancer cells. Affinity of each peptide for Id1 was determined by surface plasmon resonance (SPR) technology. The secondary structure of each peptide was studied by circular dichroism (CD) spectroscopy. Biological effects of each peptide in several cancer cells such as breast and colon cancer cells were analyzed. Results demonstrated that the peptide 3C (H-Tyr-Ile-Glu-Gly-Leu-Gln-Ala-Leu-Leu-Arg-Asp-Gln-NH(2)) not only showed high affinity for Id1 but also exhibited antiproliferative effects in HT-29 and MCF-7 cancer cells; the IC(50) value of 3C was determined as 25 microM in both cells. The percentage of sub-G1 in the cell cycle of the cancer cells treated with 5 microM of 3C was increased, indicating the induced apoptosis of cancer cells by 3C. Taken together, the peptide 3C is a promising lead compound for the development of antiproliferative agents.
Collapse
Affiliation(s)
- Chiu-Heng Chen
- Department of Chemistry, Tunghai University, Taichung, Taiwan, ROC
| | | | | | | | | |
Collapse
|
12
|
Kong B, Michalski CW, Hong X, Valkovskaya N, Rieder S, Abiatari I, Streit S, Erkan M, Esposito I, Friess H, Kleeff J. AZGP1 is a tumor suppressor in pancreatic cancer inducing mesenchymal-to-epithelial transdifferentiation by inhibiting TGF-β-mediated ERK signaling. Oncogene 2010; 29:5146-58. [PMID: 20581862 DOI: 10.1038/onc.2010.258] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Epithelial-to-mesenchymal transdifferentiation (EMT) mediated by transforming growth factor-β (TGF-β) signaling leads to aggressive cancer progression. In this study, we identified zinc-α2-glycoprotein (AZGP1, ZAG) as a tumor suppressor in pancreatic ductal adenocarcinoma whose expression is lost due to histone deacetylation. In vitro, ZAG silencing strikingly increased invasiveness of pancreatic cancer cells accompanied by the induction of a mesenchymal phenotype. Expression analysis of a set of EMT markers showed an increase in the expression of mesenchymal markers (vimentin (VIM) and integrin-α5) and a concomitant reduction in the expression of epithelial markers (cadherin 1 (CDH1), desmoplakin and keratin-19). Blockade of endogenous TGF-β signaling inhibited these morphological changes and the downregulation of CDH1, as elicited by ZAG silencing. In a ZAG-negative cell line, human recombinant ZAG (rZAG) specifically inhibited exogenous TGF-β-mediated tumor cell invasion and VIM expression. Furthermore, rZAG blocked TGF-β-mediated ERK2 phosphorylation. PCR array analysis revealed that ZAG-induced epithelial transdifferentiation was accompanied by a series of concerted cellular events including a shift in the energy metabolism and prosurvival signals. Thus, epigenetically regulated ZAG is a novel tumor suppressor essential for maintaining an epithelial phenotype.
Collapse
Affiliation(s)
- B Kong
- Department of Surgery, Technische Universität München, Munich, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Benfield AP, Whiddon BB, Clements JH, Martin SF. Structural and energetic aspects of Grb2-SH2 domain-swapping. Arch Biochem Biophys 2007; 462:47-53. [PMID: 17466257 PMCID: PMC1947945 DOI: 10.1016/j.abb.2007.03.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2006] [Revised: 03/09/2007] [Accepted: 03/10/2007] [Indexed: 12/31/2022]
Abstract
The SH2 domain of growth factor receptor-bound protein 2 (Grb2) has been the focus of numerous studies, primarily because of the important roles it plays in signal transduction. More recently, it has emerged as a useful protein to study the consequences of ligand preorganization upon energetics and structure in protein-ligand interactions. The Grb2-SH2 domain is known to form a domain-swapped dimer, and as part of our investigations toward correlating structure and energetics in biological systems, we examined the effects that domain-swapping dimerization of the Grb2-SH2 domain had upon ligand binding affinities. Isothermal titration calorimetry was performed using Grb2-SH2 in both its monomeric and domain-swapped dimeric forms and a phosphorylated tripeptide AcNH-pTyr-Val-Asn-NH(2) that is similar to the Shc sequence recognized by Grb2-SH2 in vivo. The two binding sites of domain-swapped dimer exhibited a 4- and a 13-fold reduction in ligand affinity compared to monomer. Crystal structures of peptide-bound and uncomplexed forms of Grb2-SH2 domain-swapped dimer were obtained and reveal that the orientation of residues V122, V123, and R142 may influence the conformation of W121, an amino acid that is believed to play an important role in Grb2-SH2 ligand sequence specificity. These findings suggest that domain-swapping of Grb2-SH2 not only results in a lower affinity for a Shc-derived ligand, but it may also affect ligand specificity.
Collapse
Affiliation(s)
- Aaron P Benfield
- Department of Chemistry and Biochemistry, University of Texas, Austin, TX 78712, USA
| | | | | | | |
Collapse
|
14
|
Vidal M, Liu WQ, Gril B, Lenoir C, Garbay C. Inhibitors of tyrosine kinase proteins induced Ras signaling pathway as potential anti-tumor agents. CR CHIM 2005. [DOI: 10.1016/j.crci.2005.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|