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Perla S, Qiu B, Dorry S, Yi JS, Bennett AM. Identification of Protein Tyrosine Phosphatase (PTP) Substrates. Methods Mol Biol 2024; 2743:123-133. [PMID: 38147212 DOI: 10.1007/978-1-0716-3569-8_8] [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: 12/27/2023]
Abstract
Protein tyrosine phosphorylation and dephosphorylation are key regulatory mechanisms in eukaryotes. Protein tyrosine phosphorylation and dephosphorylation are catalyzed by protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs), respectively. The combinatorial action of both PTKs and PTPs is essential for properly maintaining cellular functions. In this unit, we discuss different novel methods to identify PTP substrates. PTPs depend on specific invariant residues that enable binding to tyrosine-phosphorylated substrates and aid catalytic activity. Identifying PTP substrates has paved the way to understanding their role in distinct intracellular signaling pathways. Due to their high specific activity, the interaction between PTPs and their substrates is transient; therefore, identifying the physiological substrates of PTPs has been challenging. To identify the physiological substrates of PTPs, various PTP mutants have been generated. These PTP mutants, named "substrate-trapping mutants," lack catalytic activity but bind tightly to their tyrosine-phosphorylated substrates. Identifying the substrates for the PTPs will provide critical insight into the function of physiological and pathophysiological signal transduction. In this chapter, we describe interaction assays used to identify the PTP substrates.
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Affiliation(s)
- Sravan Perla
- Department of Pharmacology, Yale School of Medicine, New Haven, CT, USA
| | - Bin Qiu
- Department of Pharmacology, Yale School of Medicine, New Haven, CT, USA
| | - Sam Dorry
- Department of Pharmacology, Yale School of Medicine, New Haven, CT, USA
| | | | - Anton M Bennett
- Department of Pharmacology, Yale School of Medicine, New Haven, CT, USA.
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Dedigama-Arachchige PM, Acharige NPN, Zhang X, Bremer HJ, Yi Z, Pflum MKH. Identification of PP1c-PPP1R12A Substrates Using Kinase-Catalyzed Biotinylation to Identify Phosphatase Substrates. ACS OMEGA 2023; 8:35628-35637. [PMID: 37810667 PMCID: PMC10552495 DOI: 10.1021/acsomega.3c01944] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 07/21/2023] [Indexed: 10/10/2023]
Abstract
Protein phosphatase 1 regulatory subunit 12A (PPP1R12A) interacts with the catalytic subunit of protein phosphatase 1 (PP1c) to form the myosin phosphatase complex. In addition to a well-documented role in muscle contraction, the PP1c-PPP1R12A complex is associated with cytoskeleton organization, cell migration and adhesion, and insulin signaling. Despite the variety of biological functions, only a few substrates of the PP1c-PPP1R12A complex are characterized, which limit a full understanding of PP1c-PPP1R12A activities in muscle contraction and cytoskeleton regulation. Here, the chemoproteomics method Kinase-catalyzed Biotinylation to Identify Phosphatase Substrates (K-BIPS) was used to identify substrates of the PP1c-PPP1R12A complex in L6 skeletal muscle cells. K-BIPS enriched 136 candidate substrates with 14 high confidence hits. One high confidence hit, AKT1 kinase, was validated as a novel PP1c-PPP1R12A substrate. Given the previously documented role of AKT1 in PPP1R12A phosphorylation and cytoskeleton organization, the data suggest that PP1c-PPP1R12A regulates its own phosphatase activity through an AKT1-dependent feedback mechanism to influence cytoskeletal arrangement in muscle cells.
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Affiliation(s)
| | - Nuwan P N Acharige
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit 48202-3489, Michigan, United States
| | - Xiangmin Zhang
- Department of Pharmaceutical Sciences, Wayne State University, 259 Mack Ave, Detroit 48201, Michigan, United States
| | - Hannah J Bremer
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit 48202-3489, Michigan, United States
| | - Zhengping Yi
- Department of Pharmaceutical Sciences, Wayne State University, 259 Mack Ave, Detroit 48201, Michigan, United States
| | - Mary Kay H Pflum
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit 48202-3489, Michigan, United States
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3
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Suzuki M, Takeshita K, Kitamura Y, Kuribayashi M, Huang Z, Ichihara G, Oikawa S, Ichihara S. In Vitro Exposure to Glucose Alters the Expression of Phosphorylated Proteins in Platelets. Biomedicines 2023; 11:biomedicines11020543. [PMID: 36831080 PMCID: PMC9953272 DOI: 10.3390/biomedicines11020543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/30/2023] [Accepted: 02/07/2023] [Indexed: 02/16/2023] Open
Abstract
Diabetes mellitus (DM) is a pro-thrombotic state that can potentially cause serious cardiovascular complications. Platelet hyperactivation plays an important role in these pathological processes, however there is little or no information on the effect of hyperglycemia on platelet proteins. The aim of this study was to identify the molecular targets associated with platelet reactivity under hyperglycemia. Towards this goal, we examined the effects of the exposure of platelets to 1 and 2 h glucose (300 mg/dL) and control (vehicle and osmolality control using mannitol) on platelet proteins (n = 4 samples per group) using two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) combined with MALDI-TOF/TOF tandem mass spectrometry. Two-hour exposure to glucose significantly up-regulated the expression of ATP synthase subunit beta, filamin-A, and L-lactate dehydrogenase A chain in platelets. Pro-Q Diamond staining confirmed the effect of 2 h glucose on vinculin, heat shock protein HSP 90-alpha, filamin-A, and fructose-bisphosphate aldolase A (platelet phosphorylated proteins). The identified proteins are involved in various cellular processes and functions and possibly in platelet reactivity under hyperglycemic conditions.
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Affiliation(s)
- Mizuho Suzuki
- Department of Environmental and Preventive Medicine, Jichi Medical University School of Medicine, Shimotsuke 329-0498, Japan
| | - Kyosuke Takeshita
- Department of Clinical Laboratory, Saitama Medical Center, Saitama University, Saitama 350-8550, Japan
| | - Yuki Kitamura
- Department of Environmental and Preventive Medicine, Jichi Medical University School of Medicine, Shimotsuke 329-0498, Japan
| | - Marie Kuribayashi
- Department of Human Functional Genomics, Life Science Research Center, Mie University, Tsu 514-8507, Japan
| | - Zhenlie Huang
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Gaku Ichihara
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Shinji Oikawa
- Department of Environmental and Molecular Medicine, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
| | - Sahoko Ichihara
- Department of Environmental and Preventive Medicine, Jichi Medical University School of Medicine, Shimotsuke 329-0498, Japan
- Department of Human Functional Genomics, Life Science Research Center, Mie University, Tsu 514-8507, Japan
- Correspondence:
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Gene Profiling of a 3D Psoriatic Skin Model Enriched in T Cells: Downregulation of PTPRM Promotes Keratinocyte Proliferation through Excessive ERK1/2 Signaling. Cells 2022; 11:cells11182904. [PMID: 36139479 PMCID: PMC9497242 DOI: 10.3390/cells11182904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/08/2022] [Accepted: 09/13/2022] [Indexed: 12/03/2022] Open
Abstract
Psoriasis is a complex, immune-mediated skin disease involving a wide range of epithelial and immune cells. The underlying mechanisms that govern the epidermal defects and immunological dysfunction observed in this condition remain largely unknown. In recent years, the emergence of new, more sophisticated models has allowed the evolution of our knowledge of the pathogenesis of psoriasis. The development of psoriatic skin biomaterials that more closely mimic native psoriatic skin provides advanced preclinical models that will prove relevant in predicting clinical outcomes. In this study, we used a tissue-engineered, two-layered (dermis and epidermis) human skin substitute enriched in T cells as a biomaterial to study both the cellular and molecular mechanisms involved in psoriasis’ pathogenesis. Gene profiling on microarrays revealed significant changes in the profile of genes expressed by the psoriatic skin substitutes compared with the healthy ones. Two genes, namely, PTPRM and NELL2, whose products influence the ERK1/2 signaling pathway have been identified as being deregulated in psoriatic substitutes. Deregulation of these genes supports excessive activation of the ERK1/2 pathway in psoriatic skin substitutes. Most importantly, electrophoresis mobility shift assays provided evidence that the DNA-binding properties of two downstream nuclear targets of ERK1/2, both the NF-κB and Sp1 transcription factors, are increased under psoriatic conditions. Moreover, the results obtained with the inhibition of RSK, a downstream effector of ERK1/2, supported the therapeutic potential of inhibiting this signaling pathway for psoriasis treatment. In conclusion, this two-layered human psoriatic skin substitute enriched in T cells may prove particularly useful in deciphering the mechanistic details of psoriatic pathogenesis and provide a relevant biomaterial for the study of potential therapeutic targets.
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Wang C, Yuan Z, Hu R, Li F, Yue X. Association of SNPs within PTPN3 gene with wool production and growth traits in a dual-purpose sheep population. Anim Biotechnol 2022:1-7. [PMID: 35192431 DOI: 10.1080/10495398.2022.2029465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Protein tyrosine phosphatase non-receptor type 3 (PTPN3), a member of the membrane-associated non-receptor protein tyrosine phosphatase (PTP) family, plays significant roles in the cytoplasm and affects the development and growth of skin and hair. A recent study identified the PTPN3 as the potential gene related to sheep wool quality. To detect single-nucleotide polymorphisms (SNPs) of PTPN3 and elucidate its association with wool production and growth traits in fine wool sheep a total of 644 healthy SG (South African mutton merino♂ × Gansu alpine fine-wool sheep♀, SG) and SSG (South African mutton merino♂ × SG♀, SSG) hybrid sheep were selected. Pooled-DNA sequencing and SNPscan methods were used to scan and genotype SNPs within PTPN3. Association analyses between SNPs and wool production and growth traits were implemented. Consequently, the results revealed that PTPN3 has six SNPs (two missense mutations, one synonymous mutation, and three intron mutations), of which four loci (SNP2, SNP3, SNP4, and SNP5) were significantly positively correlated with growth and wool traits (p < 0.05). SNP4 was significantly (p < 0.05) linked with thigh wool length, and SNP6 was significantly (p < 0.05) associated with abdomen wool length. Moreover, one strongly linked SNP block was identified to be correlated with wool production and growth traits (body weight and body size). The significant SNPs founded by this study could serve as useful genetic markers for breeding fine-wool sheep.®.
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Affiliation(s)
- Chong Wang
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Zehu Yuan
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education, Yangzhou University, Yangzhou, China
| | - Ruixue Hu
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Fadi Li
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Xiangpeng Yue
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
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Sarmasti Emami S, Zhang D, Yang X. Interaction of the Hippo Pathway and Phosphatases in Tumorigenesis. Cancers (Basel) 2020; 12:E2438. [PMID: 32867200 PMCID: PMC7564220 DOI: 10.3390/cancers12092438] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/21/2020] [Accepted: 08/25/2020] [Indexed: 01/05/2023] Open
Abstract
The Hippo pathway is an emerging tumor suppressor signaling pathway involved in a wide range of cellular processes. Dysregulation of different components of the Hippo signaling pathway is associated with a number of diseases including cancer. Therefore, identification of the Hippo pathway regulators and the underlying mechanism of its regulation may be useful to uncover new therapeutics for cancer therapy. The Hippo signaling pathway includes a set of kinases that phosphorylate different proteins in order to phosphorylate and inactivate its main downstream effectors, YAP and TAZ. Thus, modulating phosphorylation and dephosphorylation of the Hippo components by kinases and phosphatases play critical roles in the regulation of the signaling pathway. While information regarding kinase regulation of the Hippo pathway is abundant, the role of phosphatases in regulating this pathway is just beginning to be understood. In this review, we summarize the most recent reports on the interaction of phosphatases and the Hippo pathway in tumorigenesis. We have also introduced challenges in clarifying the role of phosphatases in the Hippo pathway and future direction of crosstalk between phosphatases and the Hippo pathway.
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Affiliation(s)
| | | | - Xiaolong Yang
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (D.Z.)
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Huang M, Li J. Physiological regulation of reactive oxygen species in organisms based on their physicochemical properties. Acta Physiol (Oxf) 2020; 228:e13351. [PMID: 31344326 DOI: 10.1111/apha.13351] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 07/21/2019] [Accepted: 07/23/2019] [Indexed: 12/11/2022]
Abstract
Oxidative stress is recognized as free radical dyshomeostasis, which has damaging effects on proteins, lipids and DNA. However, during cell differentiation and proliferation and other normal physiological processes, free radicals play a pivotal role in message transmission and are considered important messengers. Organisms maintain free radical homeostasis through a sophisticated regulatory system in which these "2-faced" molecules play appropriate roles under physiological and pathological conditions. Reactive oxygen species (ROS), including a large number of free radicals, act as redox signalling molecules in essential cellular signalling pathways, including cell differentiation and proliferation. However, excessive ROS levels can induce oxidative stress, which is an important risk factor for diabetes, cancer and cardiovascular disease. An overall comprehensive understanding of ROS is beneficial for understanding the pathogenesis of certain diseases and finding new therapeutic treatments. This review primarily focuses on ROS cellular localization, sources, chemistry and molecular targets to determine how to distinguish between the roles of ROS as messengers and in oxidative stress.
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Affiliation(s)
- Mei‐Zhou Huang
- Key Lab of New Animal Drug Project of Gansu Province, Key Lab of Veterinary Pharmaceutical Development of Ministry of Agriculture Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS Lanzhou China
| | - Jian‐Yong Li
- Key Lab of New Animal Drug Project of Gansu Province, Key Lab of Veterinary Pharmaceutical Development of Ministry of Agriculture Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS Lanzhou China
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Nguyen PH, Tuan HN, Hoang DT, Vu QT, Pham MQ, Tran MH, To DC. Glucose Uptake Stimulatory and PTP1B Inhibitory Activities of Pimarane Diterpenes from Orthosiphon stamineus Benth. Biomolecules 2019; 9:biom9120859. [PMID: 31835878 PMCID: PMC7017366 DOI: 10.3390/biom9120859] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/09/2019] [Accepted: 12/09/2019] [Indexed: 11/16/2022] Open
Abstract
Seven pimarane diterpenes (1–7) were isolated from Orthosiphon stamineus Benth. by assay-guided isolation. All of the isolates possessed a 2-deoxy-2-((7-nitro-2,1,3-benzoxadiazol-4-yl)amino)-d-glucose uptake effect in 3T3-L1 adipocytes at concentrations of 5 and 10 μM. Most of them showed potent inhibition against protein tyrosine phosphatase 1B with IC50 values ranging from 0.33 to 9.84 μM. In the kinetic study, all inhibition types were exposed for the examined potencies, including mixed-competitive (1), non-competitives (3 and 5), competitive (6), and uncompetitive (7). The results suggested that O. stamineus and its pimarane diterpenes might exert the hypoglycemic effect via the insulin signaling pathway targeting inhibition of protein tyrosine phosphatase 1B (PTP1B) activity.
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Affiliation(s)
- Phi Hung Nguyen
- Institute of Natural Products Chemistry, Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Cau Giay, Hanoi 122100, Vietnam;
- Graduate University of Science and Technology, VAST, 18 Hoang Quoc Viet, Cau Giay, Hanoi 122100, Vietnam
- Correspondence: (P.H.N.); (D.C.T.)
| | - Huynh Nhu Tuan
- Faculty of Pharmacy, Dong A University, 33 Xo Viet Nghe Tinh, Hai Chau District, Da Nang 550000, Vietnam;
| | - Duc Thuan Hoang
- Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi 123106, Vietnam; (D.T.H.); (Q.T.V.)
| | - Quoc Trung Vu
- Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi 123106, Vietnam; (D.T.H.); (Q.T.V.)
| | - Minh Quan Pham
- Institute of Natural Products Chemistry, Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Cau Giay, Hanoi 122100, Vietnam;
- Graduate University of Science and Technology, VAST, 18 Hoang Quoc Viet, Cau Giay, Hanoi 122100, Vietnam
| | - Manh Hung Tran
- Biomedical Sciences Department, Institute for Research & Executive Education (VNUK), The University of Danang, 158A Le Loi, Hai Chau, Danang 551000, Vietnam;
| | - Dao Cuong To
- Faculty of Pharmacy, Phenikaa University, Yen Nghia, Ha Dong, Hanoi 12116, Vietnam
- Phenikaa Research and Technology Institute (PRATI), A&A Green Phoenix Group JSC, No.167 Hoang Ngan, Trung Hoa, Cau Giay, Hanoi 11313, Vietnam
- Correspondence: (P.H.N.); (D.C.T.)
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Hussein UK, Park HS, Bae JS, Kim KM, Chong YJ, Kim CY, Kwon KS, Chung MJ, Lee H, Kang MJ, Moon WS, Jang KY. Expression of oxidized protein tyrosine phosphatase and γH2AX predicts poor survival of gastric carcinoma patients. BMC Cancer 2018; 18:836. [PMID: 30126387 PMCID: PMC6102926 DOI: 10.1186/s12885-018-4752-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 08/14/2018] [Indexed: 11/25/2022] Open
Abstract
Background Oxidative stress induces various intracellular damage, which might be correlated with tumorigenesis. Accumulated oxidative stresses might inactivate protein tyrosine phosphatase (PTP) by oxidizing it, and inducing the phosphorylation of H2AX (γH2AX) in response to DNA damage. Methods We evaluated the clinical significance of the expression of oxidized-PTP and γH2AX in 169 gastric carcinomas. Results Immunohistochemical expression of nuclear oxidized-PTP, cytoplasmic oxidized-PTP, and γH2AX expression were significantly associated with each other, and their expressions predicted shorter survival of gastric carcinoma patients. In multivariate analysis, nuclear oxidized-PTP (overall survival; p < 0.001, relapse-free survival; P < 0.001) was an independent indicator of poor prognosis of gastric carcinoma patients. In addition, co-expression patterns of nuclear oxidized-PTP and γH2AX were independent indicators of poor prognosis of gastric carcinoma patients (overall survival; P < 0.001, relapse-free survival; P < 0.001). Conclusions This study suggests that oxidative stress-mediated oxidation of PTP might be involved in the progression of gastric carcinomas. In addition, this study suggests that individual and co-expression pattern of nuclear oxidized-PTP and γH2AX might be used as a prognostic marker of gastric carcinomas.
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Affiliation(s)
- Usama Khamis Hussein
- Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk, National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.,Research Institute for Endocrine Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea.,Faculty of Science, Beni-Suef University, Beni-Suef, Egypt
| | - Ho Sung Park
- Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk, National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.,Research Institute for Endocrine Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Jun Sang Bae
- Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk, National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.,Research Institute for Endocrine Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Kyoung Min Kim
- Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk, National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.,Research Institute for Endocrine Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Yun Jo Chong
- Center for University-wide Research Facilities, Chonbuk National University, Jeonju, Republic of Korea
| | - Chan Young Kim
- Department of Surgery, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Keun Sang Kwon
- Department of Preventive Medicine, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Myoung Ja Chung
- Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk, National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.,Research Institute for Endocrine Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Ho Lee
- Department of Forensic Medicine, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Myoung Jae Kang
- Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk, National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.,Research Institute for Endocrine Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Woo Sung Moon
- Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk, National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.,Research Institute for Endocrine Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Kyu Yun Jang
- Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk, National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea. .,Research Institute for Endocrine Sciences, Chonbuk National University Medical School, Jeonju, Republic of Korea.
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Dedigama-Arachchige PM, Acharige NPN, Pflum MKH. Identification of PP1-Gadd34 substrates involved in the unfolded protein response using K-BIPS, a method for phosphatase substrate identification. Mol Omics 2018; 14:121-133. [PMID: 29623310 DOI: 10.1039/c7mo00064b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Phosphorylation is a key post-translational modification in cell signaling, which is regulated by the equilibrium activities of kinases and phosphatases. The biological significance of many phosphorylation events remains poorly characterized due to the scarcity of tools to discover phosphatases substrates. In prior work, we established kinase-catalyzed biotinylation where kinases accept the γ-modified ATP analog, ATP-biotin, to label phosphoproteins. Here, we developed a novel method to study substrates of phosphatases using kinase-catalyzed biotinylation termed K-BIPS (Kinase-catalyzed Biotinylation to Identify Phosphatase Substrates). In a proof-of-concept experiment, K-BIPS was initially used to explore the substrates of phosphatases inhibited by okadaic acid. Many known phosphatase substrates were observed, confirming K-BIPS as a valid phosphatase substrate identification tool. Then, as a further application, K-BIPS was used to discover the substrates of the PP1-Gadd34 phosphatase complex in the context of unfolded protein response (UPR). In addition to the known substrate eIF2α, K-BIPS revealed several novel substrates, suggesting a more prominent role for the PP1-Gadd34 complex in UPR than previously appreciated. Overall, the two studies establish K-BIPS as a powerful tool to discover the cellular substrates of phosphatases.
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11
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Hamada N, Mizuno M, Tomita H, Iwamoto I, Hara A, Nagata KI. Expression analyses of Dusp22 (Dual-specificity phosphatase 22) in mouse tissues. Med Mol Morphol 2017; 51:111-117. [PMID: 29282540 DOI: 10.1007/s00795-017-0178-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 12/21/2017] [Indexed: 12/25/2022]
Abstract
Dusp22 (dual-specificity phosphatase 22) is considered to regulate various cellular processes through the regulation of protein dephosphorylation. In this study, we prepared a specific antibody against Dusp22, anti-Dusp22, and carried out expression analyses with mouse tissues and cultured cell lines. Western blotting analyses demonstrated a tissue-dependent expression profile of Dusp22 in the adult mouse, and strongly suggested the presence of isoforms with larger molecular masses. In fibroblast NIH3T3 cells, while both endogenous and Myc-tagged Dusp22 was diffusely distributed in the cytoplasm, Myc-Dusp22 was partially colocalized with actin cytoskeleton. From the obtained results, anti-Dusp22 was found to be a useful tool for biochemical and cell biological analyses of Dusp22.
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Affiliation(s)
- Nanako Hamada
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai, 480-0392, Japan
| | - Makoto Mizuno
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai, 480-0392, Japan
| | - Hiroyuki Tomita
- Department of Tumor Pathology, Gifu University Graduate School of Medicine, Gifu, 501-1194, Japan
| | - Ikuko Iwamoto
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai, 480-0392, Japan
| | - Akira Hara
- Department of Tumor Pathology, Gifu University Graduate School of Medicine, Gifu, 501-1194, Japan
| | - Koh-Ichi Nagata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya, Kasugai, 480-0392, Japan.
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Min K, Lawan A, Bennett AM. Loss of MKP-5 promotes myofiber survival by activating STAT3/Bcl-2 signaling during regenerative myogenesis. Skelet Muscle 2017; 7:21. [PMID: 29047406 PMCID: PMC5648478 DOI: 10.1186/s13395-017-0137-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 09/25/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The mitogen-activated protein kinases (MAPKs) have been shown to be involved in regulating myofiber survival. In skeletal muscle, p38 MAPK and JNK are negatively regulated by MAPK phosphatase-5 (MKP-5). During muscle regeneration, MKP-5 is downregulated, thereby promoting p38 MAPK/JNK signaling, and subsequent repair of damaged muscle. Mice lacking MKP-5 expression exhibit enhanced regenerative myogenesis. However, the effect of MKP-5 on myofiber survival during regeneration is unclear. METHODS To investigate whether MKP-5 is involved in myofiber survival, skeletal muscle injury was induced by cardiotoxin injection, and the effects on apoptosis were assessed by TUNEL assay in wild type and MKP-5-deficient mice. The contribution of MKP-5 to apoptotic signaling and its link to this pathway through mitochondrial function were determined in regenerating skeletal muscle of MKP-5-deficient mice. RESULTS We found that loss of MKP-5 in skeletal muscle resulted in improved myofiber survival. In response to skeletal muscle injury, loss of MKP-5 decreased activation of the mitochondrial apoptotic pathway involving the signal transducer and activator of transcription 3 (STAT3) and increased expression of the anti-apoptotic transcription factor Bcl-2. Skeletal muscle of MKP-5-deficient mice also exhibited an improved anti-oxidant capacity as a result of increased expression of catalase further contributing to myofiber survival by attenuating oxidative damage. CONCLUSIONS Taken together, these findings suggest that MKP-5 coordinates skeletal muscle regeneration by regulating mitochondria-mediated apoptosis. MKP-5 negatively regulates apoptotic signaling, and during regeneration, MKP-5 downregulation contributes to the restoration of myofiber survival. Finally, these results suggest that MKP-5 inhibition may serve as an important therapeutic target for the preservation of skeletal muscle survival in degenerative muscle diseases.
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Affiliation(s)
- Kisuk Min
- Department of Pharmacology, Yale University, New Haven, CT, 06520, USA
| | - Ahmed Lawan
- Department of Pharmacology, Yale University, New Haven, CT, 06520, USA
| | - Anton M Bennett
- Department of Pharmacology, Yale University, New Haven, CT, 06520, USA. .,Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University, New Haven, CT, 06520, USA.
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13
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Regulation of receptor-type protein tyrosine phosphatases by their C-terminal tail domains. Biochem Soc Trans 2017; 44:1295-1303. [PMID: 27911712 DOI: 10.1042/bst20160141] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/06/2016] [Accepted: 07/11/2016] [Indexed: 01/10/2023]
Abstract
Protein tyrosine phosphatases (PTPs) perform specific functions in vivo, despite being vastly outnumbered by their substrates. Because of this and due to the central roles PTPs play in regulating cellular function, PTP activity is regulated by a large variety of molecular mechanisms. We review evidence that indicates that the divergent C-terminal tail sequences (C-terminal domains, CTDs) of receptor-type PTPs (RPTPs) help regulate RPTP function by controlling intermolecular associations in a way that is itself subject to physiological regulation. We propose that the CTD of each RPTP defines an 'interaction code' that helps determine molecules it will interact with under various physiological conditions, thus helping to regulate and diversify PTP function.
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14
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Bongard RD, Lepley M, Thakur K, Talipov MR, Nayak J, Lipinski RAJ, Bohl C, Sweeney N, Ramchandran R, Rathore R, Sem DS. Serendipitous discovery of light-induced (In Situ) formation of an Azo-bridged dimeric sulfonated naphthol as a potent PTP1B inhibitor. BMC BIOCHEMISTRY 2017; 18:10. [PMID: 28569147 PMCID: PMC5452347 DOI: 10.1186/s12858-017-0083-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 05/10/2017] [Indexed: 02/03/2023]
Abstract
Background Protein tyrosine phosphatases (PTPs) like dual specificity phosphatase 5 (DUSP5) and protein tyrosine phosphatase 1B (PTP1B) are drug targets for diseases that include cancer, diabetes, and vascular disorders such as hemangiomas. The PTPs are also known to be notoriously difficult targets for designing inihibitors that become viable drug leads. Therefore, the pipeline for approved drugs in this class is minimal. Furthermore, drug screening for targets like PTPs often produce false positive and false negative results. Results Studies presented herein provide important insights into: (a) how to detect such artifacts, (b) the importance of compound re-synthesis and verification, and (c) how in situ chemical reactivity of compounds, when diagnosed and characterized, can actually lead to serendipitous discovery of valuable new lead molecules. Initial docking of compounds from the National Cancer Institute (NCI), followed by experimental testing in enzyme inhibition assays, identified an inhibitor of DUSP5. Subsequent control experiments revealed that this compound demonstrated time-dependent inhibition, and also a time-dependent change in color of the inhibitor that correlated with potency of inhibition. In addition, the compound activity varied depending on vendor source. We hypothesized, and then confirmed by synthesis of the compound, that the actual inhibitor of DUSP5 was a dimeric form of the original inhibitor compound, formed upon exposure to light and oxygen. This compound has an IC50 of 36 μM for DUSP5, and is a competitive inhibitor. Testing against PTP1B, for selectivity, demonstrated the dimeric compound was actually a more potent inhibitor of PTP1B, with an IC50 of 2.1 μM. The compound, an azo-bridged dimer of sulfonated naphthol rings, resembles previously reported PTP inhibitors, but with 18-fold selectivity for PTP1B versus DUSP5. Conclusion We report the identification of a potent PTP1B inhibitor that was initially identified in a screen for DUSP5, implying common mechanism of inhibitory action for these scaffolds. Electronic supplementary material The online version of this article (doi:10.1186/s12858-017-0083-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Robert D Bongard
- Center for Structure-based Drug Design and Development, Department of Pharmaceutical Sciences, Concordia University of Wisconsin, Mequon, WI, 53097, USA
| | - Michael Lepley
- Department of Pediatrics, Division of Neonatology, Department of Obstetrics and Gynecology, Children's Research Institute (CRI) Developmental Vascular Biology Program, Translational and Biomedical Research Center, 8701 Watertown Plank Road, P.O. Box 26509, Milwaukee, WI, 53226, USA
| | - Khushabu Thakur
- Department of Chemistry, Marquette University, Wehr Chemistry Building, P.O. Box 1881, 535 N. 14th Street, Milwaukee, WI, 53201, USA
| | - Marat R Talipov
- Department of Chemistry, Marquette University, Wehr Chemistry Building, P.O. Box 1881, 535 N. 14th Street, Milwaukee, WI, 53201, USA
| | - Jaladhi Nayak
- Department of Pediatrics, Division of Neonatology, Department of Obstetrics and Gynecology, Children's Research Institute (CRI) Developmental Vascular Biology Program, Translational and Biomedical Research Center, 8701 Watertown Plank Road, P.O. Box 26509, Milwaukee, WI, 53226, USA
| | - Rachel A Jones Lipinski
- Department of Pediatrics, Division of Neonatology, Department of Obstetrics and Gynecology, Children's Research Institute (CRI) Developmental Vascular Biology Program, Translational and Biomedical Research Center, 8701 Watertown Plank Road, P.O. Box 26509, Milwaukee, WI, 53226, USA.,Department of Chemistry, Marquette University, Wehr Chemistry Building, P.O. Box 1881, 535 N. 14th Street, Milwaukee, WI, 53201, USA
| | - Chris Bohl
- Center for Structure-based Drug Design and Development, Department of Pharmaceutical Sciences, Concordia University of Wisconsin, Mequon, WI, 53097, USA
| | - Noreena Sweeney
- Center for Structure-based Drug Design and Development, Department of Pharmaceutical Sciences, Concordia University of Wisconsin, Mequon, WI, 53097, USA
| | - Ramani Ramchandran
- Department of Pediatrics, Division of Neonatology, Department of Obstetrics and Gynecology, Children's Research Institute (CRI) Developmental Vascular Biology Program, Translational and Biomedical Research Center, 8701 Watertown Plank Road, P.O. Box 26509, Milwaukee, WI, 53226, USA.
| | - Rajendra Rathore
- Department of Chemistry, Marquette University, Wehr Chemistry Building, P.O. Box 1881, 535 N. 14th Street, Milwaukee, WI, 53201, USA.
| | - Daniel S Sem
- Center for Structure-based Drug Design and Development, Department of Pharmaceutical Sciences, Concordia University of Wisconsin, Mequon, WI, 53097, USA.
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15
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Corti F, Simons M. Modulation of VEGF receptor 2 signaling by protein phosphatases. Pharmacol Res 2017; 115:107-123. [PMID: 27888154 PMCID: PMC5205541 DOI: 10.1016/j.phrs.2016.11.022] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 11/18/2016] [Accepted: 11/21/2016] [Indexed: 12/21/2022]
Abstract
Phosphorylation of serines, threonines, and tyrosines is a central event in signal transduction cascades in eukaryotic cells. The phosphorylation state of any particular protein reflects a balance of activity between kinases and phosphatases. Kinase biology has been exhaustively studied and is reasonably well understood, however, much less is known about phosphatases. A large body of evidence now shows that protein phosphatases do not behave as indiscriminate signal terminators, but can function both as negative or positive regulators of specific signaling pathways. Genetic models have also shown that different protein phosphatases play precise biological roles in health and disease. Finally, genome sequencing has unveiled the existence of many protein phosphatases and associated regulatory subunits comparable in number to kinases. A wide variety of roles for protein phosphatase roles have been recently described in the context of cancer, diabetes, hereditary disorders and other diseases. In particular, there have been several recent advances in our understanding of phosphatases involved in regulation of vascular endothelial growth factor receptor 2 (VEGFR2) signaling. The receptor is the principal signaling molecule mediating a wide spectrum of VEGF signal and, thus, is of paramount significance in a wide variety of diseases ranging from cancer to cardiovascular to ophthalmic. This review focuses on the current knowledge about protein phosphatases' regulation of VEGFR2 signaling and how these enzymes can modulate its biological effects.
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Affiliation(s)
- Federico Corti
- Yale Cardiovascular Research Center, Department of Internal Medicine and Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA.
| | - Michael Simons
- Yale Cardiovascular Research Center, Department of Internal Medicine and Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA.
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16
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Ma R, Chaudhari S, Li W. Canonical Transient Receptor Potential 6 Channel: A New Target of Reactive Oxygen Species in Renal Physiology and Pathology. Antioxid Redox Signal 2016; 25:732-748. [PMID: 26937558 PMCID: PMC5079416 DOI: 10.1089/ars.2016.6661] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 02/06/2016] [Indexed: 02/07/2023]
Abstract
SIGNIFICANCE Regulation of Ca2+ signaling cascade by reactive oxygen species (ROS) is becoming increasingly evident and this regulation represents a key mechanism for control of many fundamental cellular functions. Canonical transient receptor potential (TRPC) 6, a member of Ca2+-conductive channel in the TRPC family, is widely expressed in kidney cells, including glomerular mesangial cells, podocytes, tubular epithelial cells, and vascular myocytes in renal microvasculature. Both overproduction of ROS and dysfunction of TRPC6 channel are involved in renal injury in animal models and human subjects. Although regulation of TRPC channel function by ROS has been well described in other tissues and cell types, such as vascular smooth muscle, this important cell regulatory mechanism has not been fully reviewed in kidney cells. Recent Advances: Accumulating evidence has shown that TRPC6 is a redox-sensitive channel, and modulation of TRPC6 Ca2+ signaling by altering TRPC6 protein expression or TRPC6 channel activity in kidney cells is a downstream mechanism by which ROS induce renal damage. CRITICAL ISSUES This review highlights how recent studies analyzing function and expression of TRPC6 channels in the kidney and their response to ROS improve our mechanistic understanding of oxidative stress-related kidney diseases. FUTURE DIRECTIONS Although it is evident that ROS regulate TRPC6-mediated Ca2+ signaling in several types of kidney cells, further study is needed to identify the underlying molecular mechanism. We hope that the newly identified ROS/TRPC6 pathway will pave the way to new, promising therapeutic strategies to target kidney diseases such as diabetic nephropathy. Antioxid. Redox Signal. 25, 732-748.
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Affiliation(s)
- Rong Ma
- Institute for Cardiovascular and Metabolic Diseases, University of North Texas Health Science Center, Fort Worth, Texas
| | - Sarika Chaudhari
- Institute for Cardiovascular and Metabolic Diseases, University of North Texas Health Science Center, Fort Worth, Texas
| | - Weizu Li
- Department of Pharmacology, Anhui Medical University, Hefei, People's Republic of China
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17
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Wang N, She J, Liu W, Shi J, Yang Q, Shi B, Hou P. Frequent amplification of PTP1B is associated with poor survival of gastric cancer patients. Cell Cycle 2015; 14:732-43. [PMID: 25590580 DOI: 10.1080/15384101.2014.998047] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The protein tyrosine phosphatase 1B (PTP1B), a non-transmembrane protein tyrosine phosphatase, has been implicated in gastric pathogenesis. Several lines of recent evidences have shown that PTP1B is highly amplified in breast and prostate cancers. The aim of this study was to investigate PTP1B amplification in gastric cancer and its association with poor prognosis of gastric cancer patients, and further determine the role of PTP1B in gastric tumorigenesis. Our data demonstrated that PTP1B was significantly up-regulated in gastric cancer tissues as compared with matched normal gastric tissues by using quantitative RT-PCR (qRT-PCR) assay. In addition, copy number analysis showed that PTP1B was amplified in 68/131 (51.9%) gastric cancer cases, whereas no amplification was found in the control subjects. Notably, PTP1B amplification was positively associated with its protein expression, and was significantly related to poor survival of gastric cancer patients. Knocking down PTP1B expression in gastric cancer cells significantly inhibited cell proliferation, colony formation, migration and invasion, and induced cell cycle arrested and apoptosis. Mechanically, PTP1B promotes gastric cancer cell proliferation, survival and invasiveness through modulating Src-related signaling pathways, such as Src/Ras/MAPK and Src/phosphatidylinositol-3-kinase (PI3K)/Akt pathways. Collectively, our data demonstrated frequent overexpression and amplification PTP1B in gastric cancer, and further determined the oncogenic role of PTP1B in gastric carcinogenesis. Importantly, PTP1B amplification predicts poor survival of gastric cancer patients.
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Key Words
- Akt, serine/threonine protein kinase
- DMEM, Dulbecco's modified Eagles medium
- DMSO, dimethyl sulfoxide
- EDTA, Ethylenediaminetetraacetic acid
- EMT, epithelial-to-mesenchymal transition
- Erk, elk-related tyrosine kinase
- FAK, focal adhesion kinase
- FITC, fluoresceine isothiocyanate
- FOXO3a, Forkhead class O transcription factor 3a
- Gastric cancer
- H&E, hematoxylin and eosin
- HR, hazard ratio
- HRP, horseradish peroxidase
- IHC, immunohistochemistry
- MAPK, mitogen-activated protein kinase
- MMPs, metalloproteinases
- MTT, 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide
- Mdm2, mouse double minute 2
- PBS, phosphate buffered saline
- PI3K, phosphatidylinositol 3-kinase
- PTP1B
- PTP1B, protein tyrosine phosphatase 1B
- PVDF, polyvinylidene fluoride
- RPMI 1640, Roswell Park Memorial Institute 1640
- RT-PCR, Reverse-transcription polymerase chain reaction
- SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis
- genomic amplification
- poor prognosis
- siRNA, short interfering RNA.
- signaling pathways
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Affiliation(s)
- Na Wang
- a Department of Endocrinology ; The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine ; Xi'an , People's Republic of China
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Bruntz RC, Lindsley CW, Brown HA. Phospholipase D signaling pathways and phosphatidic acid as therapeutic targets in cancer. Pharmacol Rev 2015; 66:1033-79. [PMID: 25244928 DOI: 10.1124/pr.114.009217] [Citation(s) in RCA: 161] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Phospholipase D is a ubiquitous class of enzymes that generates phosphatidic acid as an intracellular signaling species. The phospholipase D superfamily plays a central role in a variety of functions in prokaryotes, viruses, yeast, fungi, plants, and eukaryotic species. In mammalian cells, the pathways modulating catalytic activity involve a variety of cellular signaling components, including G protein-coupled receptors, receptor tyrosine kinases, polyphosphatidylinositol lipids, Ras/Rho/ADP-ribosylation factor GTPases, and conventional isoforms of protein kinase C, among others. Recent findings have shown that phosphatidic acid generated by phospholipase D plays roles in numerous essential cellular functions, such as vesicular trafficking, exocytosis, autophagy, regulation of cellular metabolism, and tumorigenesis. Many of these cellular events are modulated by the actions of phosphatidic acid, and identification of two targets (mammalian target of rapamycin and Akt kinase) has especially highlighted a role for phospholipase D in the regulation of cellular metabolism. Phospholipase D is a regulator of intercellular signaling and metabolic pathways, particularly in cells that are under stress conditions. This review provides a comprehensive overview of the regulation of phospholipase D activity and its modulation of cellular signaling pathways and functions.
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Affiliation(s)
- Ronald C Bruntz
- Department of Pharmacology (R.C.B., C.W.L., H.A.B.) and Vanderbilt Center for Neuroscience Drug Discovery (C.W.L.), Vanderbilt University Medical Center; Department of Chemistry, Vanderbilt Institute of Chemical Biology (C.W.L., H.A.B.); Vanderbilt Specialized Chemistry for Accelerated Probe Development (C.W.L.); and Department of Biochemistry, Vanderbilt-Ingram Cancer Center (H.A.B.), Vanderbilt University, Nashville, Tennessee
| | - Craig W Lindsley
- Department of Pharmacology (R.C.B., C.W.L., H.A.B.) and Vanderbilt Center for Neuroscience Drug Discovery (C.W.L.), Vanderbilt University Medical Center; Department of Chemistry, Vanderbilt Institute of Chemical Biology (C.W.L., H.A.B.); Vanderbilt Specialized Chemistry for Accelerated Probe Development (C.W.L.); and Department of Biochemistry, Vanderbilt-Ingram Cancer Center (H.A.B.), Vanderbilt University, Nashville, Tennessee
| | - H Alex Brown
- Department of Pharmacology (R.C.B., C.W.L., H.A.B.) and Vanderbilt Center for Neuroscience Drug Discovery (C.W.L.), Vanderbilt University Medical Center; Department of Chemistry, Vanderbilt Institute of Chemical Biology (C.W.L., H.A.B.); Vanderbilt Specialized Chemistry for Accelerated Probe Development (C.W.L.); and Department of Biochemistry, Vanderbilt-Ingram Cancer Center (H.A.B.), Vanderbilt University, Nashville, Tennessee
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Phosphotyrosine Substrate Sequence Motifs for Dual Specificity Phosphatases. PLoS One 2015; 10:e0134984. [PMID: 26302245 PMCID: PMC4547750 DOI: 10.1371/journal.pone.0134984] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 07/13/2015] [Indexed: 12/19/2022] Open
Abstract
Protein tyrosine phosphatases dephosphorylate tyrosine residues of proteins, whereas, dual specificity phosphatases (DUSPs) are a subgroup of protein tyrosine phosphatases that dephosphorylate not only Tyr(P) residue, but also the Ser(P) and Thr(P) residues of proteins. The DUSPs are linked to the regulation of many cellular functions and signaling pathways. Though many cellular targets of DUSPs are known, the relationship between catalytic activity and substrate specificity is poorly defined. We investigated the interactions of peptide substrates with select DUSPs of four types: MAP kinases (DUSP1 and DUSP7), atypical (DUSP3, DUSP14, DUSP22 and DUSP27), viral (variola VH1), and Cdc25 (A-C). Phosphatase recognition sites were experimentally determined by measuring dephosphorylation of 6,218 microarrayed Tyr(P) peptides representing confirmed and theoretical phosphorylation motifs from the cellular proteome. A broad continuum of dephosphorylation was observed across the microarrayed peptide substrates for all phosphatases, suggesting a complex relationship between substrate sequence recognition and optimal activity. Further analysis of peptide dephosphorylation by hierarchical clustering indicated that DUSPs could be organized by substrate sequence motifs, and peptide-specificities by phylogenetic relationships among the catalytic domains. The most highly dephosphorylated peptides represented proteins from 29 cell-signaling pathways, greatly expanding the list of potential targets of DUSPs. These newly identified DUSP substrates will be important for examining structure-activity relationships with physiologically relevant targets.
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20
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Wagner S, Schütz A, Rademann J. Light-switched inhibitors of protein tyrosine phosphatase PTP1B based on phosphonocarbonyl phenylalanine as photoactive phosphotyrosine mimetic. Bioorg Med Chem 2015; 23:2839-47. [PMID: 25907367 DOI: 10.1016/j.bmc.2015.03.074] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 03/23/2015] [Accepted: 03/24/2015] [Indexed: 11/24/2022]
Abstract
Phosphopeptide mimetics containing the 4-phosphonocarbonyl phenylalanine (pcF) as a photo-active phosphotyrosine isoster are developed as potent, light-switchable inhibitors of the protein tyrosine phosphatase PTP1B. The photo-active inhibitors 6-10 are derived from phosphopeptide substrates and are prepared from the suitably protected pcF building block 12 by Fmoc-based solid phase peptide synthesis. All pcF-containing peptides are moderate inhibitors of PTP1B with KI values between 10 and 50μM. Irradiation of the inhibitors at 365nm in the presence of the protein PTP1B amplify the inhibitory activity of pcF-peptides up to 120-fold, switching the KI values of the best inhibitors to the sub-micromolar range. Photo-activation of the inhibitors results in the formation of triplet intermediates of the benzoylphosphonate moiety, which deactivate PTP1B following an oxidative radical mechanism. Deactivation of PTP1B proceeds without covalent crosslinking of the protein target with the photo-switched inhibitors and can be reverted by subsequent addition of reducing agent dithiothreitol (DTT).
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Affiliation(s)
- Stefan Wagner
- Freie Universität Berlin, Institute of Pharmacy, Medicinal Chemistry, Königin-Luise-Str. 2+4, 14195 Berlin, Germany
| | - Anja Schütz
- Max-Delbrück-Center for Molecular Medicine (MDC), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Jörg Rademann
- Freie Universität Berlin, Institute of Pharmacy, Medicinal Chemistry, Königin-Luise-Str. 2+4, 14195 Berlin, Germany.
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21
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Skelton LA, Boron WF. Effect of acute acid-base disturbances on the phosphorylation of phospholipase C-γ1 and Erk1/2 in the renal proximal tubule. Physiol Rep 2015; 3:e12280. [PMID: 25780091 PMCID: PMC4393148 DOI: 10.14814/phy2.12280] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 11/20/2014] [Accepted: 11/24/2014] [Indexed: 11/24/2022] Open
Abstract
The renal proximal tubule (PT) plays a major role in whole-body pH homeostasis by secreting H(+) into the tubule lumen. Previous work demonstrated that PTs respond to basolateral changes in [CO2] and [HCO3-] by appropriately altering H(+) secretion-responses blocked by the ErbB inhibitor PD168393, or by eliminating signaling through AT1 angiotensin receptors. In the present study, we analyze phosphorylation of three downstream targets of both ErbBs and AT1: phospholipase C-γ1 (PLC-γ1), extracellular-regulated kinase 1 (Erk1), and Erk2. We expose rabbit PT suspensions for 5 and 20 min to our control (Ctrl) condition (5% CO2, 22 mmol/L HCO3-, pH 7.40) or one of several conditions that mimic acid-base disturbances. We found that each disturbance produces characteristic phosphorylation patterns in the three enzymes. For example, respiratory acidosis (elevated [CO2], normal [HCO3-]) at 20 min decreases PLC-γ1 phosphorylation at tyrosine-783 (relative to Ctrl). Metabolic acidosis (normal [CO2], decreased [HCO3-]) for 5 min increases Erk1 phosphorylation (p-Erk1) but not p-Erk2, whereas metabolic alkalosis (normal [CO2], elevated [HCO3-]) for 5 min decreases p-Erk1 and p-Erk2. In the presence of CO2/HCO3-, PD168393 blocks only two of eight induced decreases in phosphorylation. In two cases in which disturbances have no remarkable effects on phosphorylation, PD168393 unmasks decreases and in two others, increases. These drug effects provide insight into the roles of PD168393-sensitive kinases. Our results indicate that PLC-γ1.pY783, p-Erk1, and p-Erk2 in the PT change in characteristic ways in response to acute acid-base disturbances, and thus presumably contribute to the transduction of acid-base signals.
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Affiliation(s)
- Lara A Skelton
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
| | - Walter F Boron
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
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Abstract
For a time, mast cells were viewed as simple granulocytic effector cells that mediate allergic symptoms. More recent discoveries show that mast cells can also function as potent pro- and anti-inflammatory immune regulators in a plethora of human diseases. Much of the current knowledge about mast cell functions comes from studies on rodent models. The membrane receptors for antigen/IgE and growth factors are the core initiators of signaling cascades that trigger various mast cell responses. Yet, the regulation and multifunctionality of key receptor-proximal protein tyrosine phosphorylation events are still not well understood. The roles of the members of the protein tyrosine phosphatase superfamily of enzymes in regulating mast cell development, survival, and immune activation will be reviewed in this chapter.
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23
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Identification of receptor protein tyrosine phosphatases (RPTPs) as regulators of receptor tyrosine kinases (RTKs) using an RPTP siRNA-RTK substrate screen. Methods Mol Biol 2014; 1233:111-20. [PMID: 25319894 DOI: 10.1007/978-1-4939-1789-1_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Receptor tyrosine kinase (RTK) signaling exists in equilibrium between RTK tyrosyl phosphorylation and RTK tyrosyl dephosphorylation. Despite a detailed understanding of RTK tyrosyl phosphorylation, much less is known about RTK tyrosyl dephosphorylation. The receptor PTPs (RPTPs) are outstanding targets for the dephosphorylation of RTKs because of their mutual membrane proximity. In this chapter, we describe how to identify RPTPs that modulate the activity of RTKs using a siRNA screen and commercially available proteomic applications. The validation of putative RTKs as RPTP substrates using substrate-trapping approaches is detailed.
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Lee H, Yi JS, Lawan A, Min K, Bennett AM. Mining the function of protein tyrosine phosphatases in health and disease. Semin Cell Dev Biol 2014; 37:66-72. [PMID: 25263013 DOI: 10.1016/j.semcdb.2014.09.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 09/21/2014] [Indexed: 12/31/2022]
Abstract
Protein tyrosine phosphatases (PTPs) play a crucial role in the regulation of human health and it is now clear that PTP dysfunction is causal to a variety of human diseases. Research in the PTP field has accelerated dramatically over the last decade fueled by cutting-edge technologies in genomic and proteomic techniques. This system-wide non-biased approach when applied to the discovery of PTP function has led to the elucidation of new and unanticipated roles for the PTPs. These discoveries, driven by genomic and proteomic approaches, have uncovered novel PTP findings that range from those that describe fundamental cell signaling mechanisms to implications for PTPs as novel therapeutic targets for the treatment of human disease. This review will discuss how new PTP functions have been uncovered through studies that have utilized genomic and proteomic technologies and strategies.
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Affiliation(s)
- Hojin Lee
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Jae-Sung Yi
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Ahmed Lawan
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Kisuk Min
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, USA
| | - Anton M Bennett
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, USA; Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT, USA.
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25
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Hwang BM, Chae HS, Jeong YJ, Lee YR, Noh EM, Youn HZ, Jung SH, Yu HN, Chung EY, Kim JS. Protein tyrosine phosphatase controls breast cancer invasion through the expression of matrix metalloproteinase-9. BMB Rep 2014; 46:533-8. [PMID: 24152909 PMCID: PMC4133842 DOI: 10.5483/bmbrep.2013.46.11.053] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 03/19/2013] [Accepted: 03/26/2013] [Indexed: 11/20/2022] Open
Abstract
The expression of matrix metalloproteinases (MMPs) produced by cancer cells has been associated with the high potential of metastasis in several human carcinomas, including breast cancer. Several pieces of evidence demonstrate that protein tyrosine phosphatases (PTP) have functions that promote cell migration and metastasis in breast cancer. We analyzed whether PTP inhibitor might control breast cancer invasion through MMP expression. Herein, we investigate the effect of 4-hydroxy-3,3-dimethyl-2H benzo[g]indole-2,5(3H)-dione (BVT948), a novel PTP inhibitor, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. The expression of MMP-9 and cell invasion increased after TPA treatment, whereas TPA-induced MMP-9 expression and cell invasion were decreased by BVT948 pretreatment. Also, BVT948 suppressed NF-κB activation in TPA-treated MCF-7 cells. However, BVT948 didn’t block TPA-induced AP-1 activation in MCF-7 cells. Our results suggest that the PTP inhibitor blocks breast cancer invasion via suppression of the expression of MMP-9. [BMB Reports 2013; 46(11): 533-538]
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Affiliation(s)
- Bo-Mi Hwang
- Departments of Biochemistry, Chonbuk National University Medical School, Jeonju 560-756, Korea
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26
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Cadet JL, Brannock C, Jayanthi S, Krasnova IN. Transcriptional and epigenetic substrates of methamphetamine addiction and withdrawal: evidence from a long-access self-administration model in the rat. Mol Neurobiol 2014; 51:696-717. [PMID: 24939695 PMCID: PMC4359351 DOI: 10.1007/s12035-014-8776-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 06/01/2014] [Indexed: 01/06/2023]
Abstract
Methamphetamine use disorder is a chronic neuropsychiatric disorder characterized by recurrent binge episodes, intervals of abstinence, and relapses to drug use. Humans addicted to methamphetamine experience various degrees of cognitive deficits and other neurological abnormalities that complicate their activities of daily living and their participation in treatment programs. Importantly, models of methamphetamine addiction in rodents have shown that animals will readily learn to give themselves methamphetamine. Rats also accelerate their intake over time. Microarray studies have also shown that methamphetamine taking is associated with major transcriptional changes in the striatum measured within a short or longer time after cessation of drug taking. After a 2-h withdrawal time, there was increased expression of genes that participate in transcription regulation. These included cyclic AMP response element binding (CREB), ETS domain-containing protein (ELK1), and members of the FOS family of transcription factors. Other genes of interest include brain-derived neurotrophic factor (BDNF), tyrosine kinase receptor, type 2 (TrkB), and synaptophysin. Methamphetamine-induced transcription was found to be regulated via phosphorylated CREB-dependent events. After a 30-day withdrawal from methamphetamine self-administration, however, there was mostly decreased expression of transcription factors including junD. There was also downregulation of genes whose protein products are constituents of chromatin-remodeling complexes. Altogether, these genome-wide results show that methamphetamine abuse might be associated with altered regulation of a diversity of gene networks that impact cellular and synaptic functions. These transcriptional changes might serve as triggers for the neuropsychiatric presentations of humans who abuse this drug. Better understanding of the way that gene products interact to cause methamphetamine addiction will help to develop better pharmacological treatment of methamphetamine addicts.
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Affiliation(s)
- Jean Lud Cadet
- Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, DHHS, 251 Bayview Boulevard, Baltimore, MD, 21224, USA,
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Selner NG, Luechapanichkul R, Chen X, Neel BG, Zhang ZY, Knapp S, Bell CE, Pei D. Diverse levels of sequence selectivity and catalytic efficiency of protein-tyrosine phosphatases. Biochemistry 2014; 53:397-412. [PMID: 24359314 PMCID: PMC3954597 DOI: 10.1021/bi401223r] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The sequence selectivity of 14 classical protein-tyrosine phosphatases (PTPs) (PTPRA, PTPRB, PTPRC, PTPRD, PTPRO, PTP1B, SHP-1, SHP-2, HePTP, PTP-PEST, TCPTP, PTPH1, PTPD1, and PTPD2) was systematically profiled by screening their catalytic domains against combinatorial peptide libraries. All of the PTPs exhibit similar preference for pY peptides rich in acidic amino acids and disfavor positively charged sequences but differ vastly in their degrees of preference/disfavor. Some PTPs (PTP-PEST, SHP-1, and SHP-2) are highly selective for acidic over basic (or neutral) peptides (by >10(5)-fold), whereas others (PTPRA and PTPRD) show no to little sequence selectivity. PTPs also have diverse intrinsic catalytic efficiencies (kcat/KM values against optimal substrates), which differ by >10(5)-fold due to different kcat and/or KM values. Moreover, PTPs show little positional preference for the acidic residues relative to the pY residue. Mutation of Arg47 of PTP1B, which is located near the pY-1 and pY-2 residues of a bound substrate, decreased the enzymatic activity by 3-18-fold toward all pY substrates containing acidic residues anywhere within the pY-6 to pY+5 region. Similarly, mutation of Arg24, which is situated near the C-terminus of a bound substrate, adversely affected the kinetic activity of all acidic substrates. A cocrystal structure of PTP1B bound with a nephrin pY(1193) peptide suggests that Arg24 engages in electrostatic interactions with acidic residues at the pY+1, pY+2, and likely other positions. These results suggest that long-range electrostatic interactions between positively charged residues near the PTP active site and acidic residues on pY substrates allow a PTP to bind acidic substrates with similar affinities, and the varying levels of preference for acidic sequences by different PTPs are likely caused by the different electrostatic potentials near their active sites. The implications of the varying sequence selectivity and intrinsic catalytic activities with respect to PTP in vivo substrate specificity and biological functions are discussed.
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Affiliation(s)
- Nicholas G. Selner
- Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12 Avenue, Columbus, OH 43210, USA
| | - Rinrada Luechapanichkul
- Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12 Avenue, Columbus, OH 43210, USA
| | - Xianwen Chen
- Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12 Avenue, Columbus, OH 43210, USA
| | - Benjamin G. Neel
- Princess Margaret Cancer Center, University Health Network, and Department of Medical Biophysics, University of Toronto, 610 University Avenue, Room 7-504, Toronto, ON M5G 2M9, Canada
| | - Zhong-Yin Zhang
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Stefan Knapp
- Structural Genomics Consortium and Target Discovery Institute, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Charles E. Bell
- Department of Molecular and Cellular Biochemistry, The Ohio State University, 1645 Neil Avenue, Columbus, OH 43210
| | - Dehua Pei
- Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12 Avenue, Columbus, OH 43210, USA
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28
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Overexpression of PTP1B in human colorectal cancer and its association with tumor progression and prognosis. J Mol Histol 2013; 45:153-9. [PMID: 23990346 DOI: 10.1007/s10735-013-9536-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Accepted: 08/20/2013] [Indexed: 01/22/2023]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a non-transmembrane protein tyrosine phosphatase that has been implicated in cancer pathogenesis. However, the expression level and the role of PTP1B in the development and prognosis of colorectal cancer (CRC) remain unclear. In this study, the expression of PTP1B in CRC tissues and matched noncancerous tissues were detected by using immunohistochemistry, real-time PCR and Western blotting. The correlations between PTP1B expression level and clinicopathologic characteristics and patient survival were analyzed. We found that PTP1B expression was significantly higher in CRC tissues compared with matched non-tumour tissues. Statistical analysis showed that the PTP1B expression was correlated with tumor differentiation, tumor invasion, lymph node metastasis, and TNM stage. Patients with higher expressions of PTP1B had the lower survival (P = 0.012). Taken together, our results suggest that PTP1B expression might play a critical role in the progression of CRC and may serve as a valuable prognostic biomarker for CRC.
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Zhang J, Chen L, Sun L. SmLMWPTP, a teleost low molecular weight protein tyrosine phosphatase, inhibits the immune response of peripheral blood leukocytes in a manner that depends on the conserved P-loop. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2013; 40:103-111. [PMID: 23500512 DOI: 10.1016/j.dci.2013.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Revised: 03/01/2013] [Accepted: 03/04/2013] [Indexed: 06/01/2023]
Abstract
Protein tyrosine phosphatases (PTPs) are a family of enzymes that play a key role in cellular signal transduction. Low molecular weight PTPs (LMWPTPs) are a subfamily of PTPs that are characterized by the presence of a conserved phosphate-binding loop (P-loop) with the signature sequence of (V/I)CXGNXCRS. To date, very little study on teleost LMWPTPs has been documented, and, as a result, the function of LMWPTPs in fish is essentially unknown. In this study, we identified a LMWPTP from turbot (Scophthalmus maximus) and examined its biological activity and functionality. The turbot LMWPTP (SmLMWPTP) is composed of 158 residues and possesses a typical P-loop sequence in the form of (12)VCLGNICRS(20). Purified recombinant SmLMWPTP (rSmLMWPTP) exhibited apparent phosphatase activity, which was optimal at pH 5 and 50°C. The activity of SmLMWPTP was abolished when C13 and, in particular, R19 of the P-loop were mutated. SmLMWPTP expression was detected in a wide range of tissues and upregulated by bacterial and viral infection. Subcellular localization analysis showed that SmLMWPTP was secreted by peripheral blood leukocytes (PBL) into the extracellular milieu. When PBL were treated with rSmLMWPTP, the cells exhibited significant reductions in (i) proliferative and respiratory burst activity, (ii) expression levels of multiple immune relevant genes, and (iii) phagocytic activity. In contrast, the mutant SmLMWPTP bearing R19 mutation had no effect on PBL activity. Taken together, these results indicate that SmLMWPTP is a secreted PTP that exerts a negative regulatory effect on the innate immune response of PBL in a manner that depends on the structural integrity of the P-loop.
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Affiliation(s)
- Jian Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
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30
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Lee H, Bennett AM. Receptor protein tyrosine phosphatase-receptor tyrosine kinase substrate screen identifies EphA2 as a target for LAR in cell migration. Mol Cell Biol 2013; 33:1430-41. [PMID: 23358419 PMCID: PMC3624262 DOI: 10.1128/mcb.01708-12] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 01/23/2013] [Indexed: 01/08/2023] Open
Abstract
Receptor tyrosine kinases (RTKs) exist in equilibrium between tyrosyl-phosphorylated and dephosphorylated states. Despite a detailed understanding of how RTKs become tyrosyl phosphorylated, much less is known about RTK tyrosyl dephosphorylation. Receptor protein tyrosine phosphatases (RPTPs) can play essential roles in the dephosphorylation of RTKs. However, a complete understanding of the involvement of the RPTP subfamily in RTK tyrosyl dephosphorylation has not been established. In this study, we have employed a small interfering RNA (siRNA) screen to identify RPTPs in the human genome that serve as RTK phosphatases. We observed that each RPTP induced a unique fingerprint of tyrosyl phosphorylation among 42 RTKs. We identified EphA2 as a novel LAR substrate. LAR dephosphorylated EphA2 at phosphotyrosyl 930, uncoupling Nck1 from EphA2 and thereby attenuating EphA2-mediated cell migration. These results demonstrate that each RPTP exerts a unique regulatory fingerprint of RTK tyrosyl dephosphorylation and suggest a complex signaling interplay between RTKs and RPTPs. Furthermore, we observed that LAR modulates cell migration through EphA2 site-specific dephosphorylation.
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Affiliation(s)
| | - Anton M. Bennett
- Department of Pharmacology
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut, USA
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31
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The brain Renin-Angiotensin system and mitochondrial function: influence on blood pressure and baroreflex in transgenic rat strains. Int J Hypertens 2013; 2013:136028. [PMID: 23401750 PMCID: PMC3564433 DOI: 10.1155/2013/136028] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 12/23/2012] [Indexed: 02/07/2023] Open
Abstract
Mitochondrial dysfunction is implicated in many cardiovascular diseases, including hypertension, and may be associated with an overactive renin-angiotensin system (RAS). Angiotensin (Ang) II, a potent vasoconstrictor hormone of the RAS, also impairs baroreflex and mitochondrial function. Most deleterious cardiovascular actions of Ang II are thought to be mediated by NADPH-oxidase- (NOX-) derived reactive oxygen species (ROS) that may also stimulate mitochondrial oxidant release and alter redox-sensitive signaling pathways in the brain. Within the RAS, the actions of Ang II are counterbalanced by Ang-(1–7), a vasodilatory peptide known to mitigate against increased oxidant stress. A balance between Ang II and Ang-(1–7) within the brain dorsal medulla contributes to maintenance of normal blood pressure and proper functioning of the arterial baroreceptor reflex for control of heart rate. We propose that Ang-(1–7) may negatively regulate the redox signaling pathways activated by Ang II to maintain normal blood pressure, baroreflex, and mitochondrial function through attenuating ROS (NOX-generated and/or mitochondrial).
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32
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Lountos GT, Tropea JE, Waugh DS. Structure of the Trypanosoma cruzi protein tyrosine phosphatase TcPTP1, a potential therapeutic target for Chagas' disease. Mol Biochem Parasitol 2013; 187:1-8. [PMID: 23137716 PMCID: PMC4197799 DOI: 10.1016/j.molbiopara.2012.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 10/22/2012] [Accepted: 10/26/2012] [Indexed: 12/26/2022]
Abstract
Chagas' disease, a neglected tropical affliction transmitted by the flagellated protozoan Trypanosoma cruzi, is prevalent in Latin America and affects nearly 18 million people worldwide, yet few approved drugs are available to treat the disease. Moreover, the currently available drugs exhibit severe toxicity or are poorly effective in the chronic phase of the disease. This limitation, along with the large population at risk, underscores the urgent need to discover new molecular targets and novel therapeutic agents. Recently, the T. cruzi protein tyrosine phosphatase TcPTP1 has been implicated in the cellular differentiation and infectivity of the parasite and is therefore a promising target for the design of novel anti-parasitic drugs. Here, we report the X-ray crystal structure of TcPTP1 refined to a resolution of 2.18 Å, which provides structural insights into the active site environment that can be used to initiate structure-based drug design efforts to develop specific TcPTP1 inhibitors. Potential strategies to develop such inhibitors are also discussed.
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Affiliation(s)
- George T. Lountos
- Basic Science Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
- Macromolecular Crystallography Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Joseph E. Tropea
- Macromolecular Crystallography Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - David S. Waugh
- Macromolecular Crystallography Laboratory, Center for Cancer Research, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
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33
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Kuban-Jankowska A, Tuszynski JA, Winter P, Gorska M, Knap N, Wozniak M. Activation of hydrogen peroxide to peroxytetradecanoic acid is responsible for potent inhibition of protein tyrosine phosphatase CD45. PLoS One 2012; 7:e52495. [PMID: 23300686 PMCID: PMC3531430 DOI: 10.1371/journal.pone.0052495] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2012] [Accepted: 11/19/2012] [Indexed: 11/19/2022] Open
Abstract
Hydrogen peroxide induces oxidation and consequently inactivation of many protein tyrosine phosphatases. It was found that hydrogen peroxide, in the presence of carboxylic acids, was efficiently activated to form even more potent oxidant - peroxy acid. We have found that peroxytetradecanoic acid decreases the enzymatic activity of CD45 phosphatase significantly more than hydrogen peroxide. Our molecular docking computational analysis suggests that peroxytetradecanoic acid has a higher binding affinity to the catalytic center of CD45 than hydrogen peroxide.
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Affiliation(s)
- Alicja Kuban-Jankowska
- Department of Medical Chemistry, Medical University of Gdansk, Gdansk, Poland
- * E-mail: (AKJ); (MW)
| | - Jack A. Tuszynski
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada
| | - Philip Winter
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada
| | - Magdalena Gorska
- Department of Medical Chemistry, Medical University of Gdansk, Gdansk, Poland
| | - Narcyz Knap
- Department of Medical Chemistry, Medical University of Gdansk, Gdansk, Poland
| | - Michal Wozniak
- Department of Medical Chemistry, Medical University of Gdansk, Gdansk, Poland
- College of Health, Beauty Care and Education in Poznan, Faculty in Gdynia, Gdynia, Poland
- * E-mail: (AKJ); (MW)
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34
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Protein phosphatase 1b in the solitary tract nucleus is necessary for normal baroreflex function. J Cardiovasc Pharmacol 2012; 59:472-8. [PMID: 22569287 DOI: 10.1097/fjc.0b013e31824ba490] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Despite positive metabolic effects, genetic deletion of protein phosphatase 1b (PTP1b) results in sympathetically mediated elevations in arterial pressure (AP) in mice. Because several PTP1b-regulated peptides also impair the baroreflex sensitivity (BRS) for control of heart rate (HR), we hypothesized that PTP1b in the solitary tract nucleus (NTS) participates in the maintenance of resting baroreflex function. To test this hypothesis, we performed acute bilateral microinjection of an allosteric PTP1b inhibitor (100 nM/120 nL) in the NTS of urethane/chloralose anesthetized Sprague-Dawley rats and assessed the BRS, responses to cardiac vagal chemosensitive fiber activation, and resting AP and HR before and after the injection. PTP1b inhibition impaired the BRS for bradycardia (n = 6; 0.93 ± 0.14 baseline vs. 0.48 ± 0.04 at 10 minutes vs. 0.49 ± 0.04 millisecond/mm Hg at 60 minutes; P < 0.01), with no significant effect on the BRS for tachycardia (0.30 ± 0.16 baseline vs. 0.24 ± 0.08 at 10 minutes vs. 0.24 ± 0.12 millisecond/mm Hg at 60 minutes). The reduced BRS for bradycardia was associated with a significant decrease in alpha-adrenergic responsiveness to phenylephrine at 60 minutes after PTP1b inhibition. Injection of the PTP1b inhibitor in the NTS elicited transient decreases in AP and HR in these animals. However, there was no effect of the inhibitor on depressor or bradycardic responses elicited by activation of cardiac vagal chemosensitive fibers, which converge with baroreceptor afferents in the NTS. These results suggest that PTP1b within the NTS may be a novel molecular mechanism for preservation of resting baroreflex function and provides further evidence for deleterious cardiovascular effects associated with PTP1b inhibition.
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35
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Bahta M, Liu F, Kim SE, Stephen AG, Fisher RJ, Burke TR. Oxime-based linker libraries as a general approach for the rapid generation and screening of multidentate inhibitors. Nat Protoc 2012; 7:686-702. [PMID: 22422315 PMCID: PMC3727389 DOI: 10.1038/nprot.2012.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The described oxime-based library protocol provides detailed procedures for the linkage of aminooxy functionality with aldehyde building blocks that result in the generation of libraries of multidentate inhibitors. Synthesis of inhibitors for protein tyrosine phosphatases (PTPs) and antagonists directed against the human tumor susceptibility gene 101 (TSG101) are shown as examples. Three steps are involved: (i) the design and synthesis of aminooxy platforms; (ii) tethering with aldehydes to form oxime-based linkages with sufficient purity; and (iii) direct in vitro biological evaluation of oxime products without purification. Each coupling reaction is (i) performed in capped microtubes at room temperature (20-23 °C); (ii) diluted for inhibitory evaluation; and (iii) screened with targets in microplates to provide IC(50) or K(d) values. The synthesis of the aminooxy platforms takes 3-5 d; tethering with the aldehydes takes 24 h; and inhibition assay of enzymes and protein-protein interactions takes 30 min and 2 h, respectively.
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Affiliation(s)
- Medhanit Bahta
- Chemical Biology Laboratory, Molecular Discovery Program, Center for Cancer Research, National Cancer Institute, US National Institutes of Health, National Cancer Institute-Frederick, Frederick, Maryland, USA
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36
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Maccari R, Ottanà R. Low molecular weight phosphotyrosine protein phosphatases as emerging targets for the design of novel therapeutic agents. J Med Chem 2011; 55:2-22. [PMID: 21988196 DOI: 10.1021/jm200607g] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Rosanna Maccari
- Dipartimento Farmaco-Chimico, Faculty of Pharmacy, University of Messina, Polo Universitario dell'Annunziata, 98168 Messina, Italy.
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37
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Protein tyrosine phosphatases as drug targets: strategies and challenges of inhibitor development. Future Med Chem 2011; 2:1563-76. [PMID: 21426149 DOI: 10.4155/fmc.10.241] [Citation(s) in RCA: 217] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Several 'classical' protein tyrosine phosphatases are attractive therapeutic targets, including PTP1B for obesity and Type II diabetes; SHP2 for cancer and Lyp for rheumatoid arthritis. Progress has been made in identifying a broad range of chemically distinct inhibitors; however, developing selective and cell-permeable clinically useful compounds has proved challenging. Here the ongoing challenges and recent significant advances in the field are reviewed. Key novel compounds are highlighted and a perspective on the future of phosphatase inhibitor development is presented.
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38
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Phillips-Mason PJ, Craig SEL, Brady-Kalnay SM. Should I stay or should I go? Shedding of RPTPs in cancer cells switches signals from stabilizing cell-cell adhesion to driving cell migration. Cell Adh Migr 2011; 5:298-305. [PMID: 21785275 DOI: 10.4161/cam.5.4.16970] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Dissolution of cell-cell adhesive contacts and increased cell-extracellular matrix adhesion are hallmarks of the migratory and invasive phenotype of cancer cells. These changes are facilitated by growth factor binding to receptor protein tyrosine kinases (RTKs). In normal cells, cell-cell adhesion molecules (CAMs), including some receptor protein tyrosine phosphatases (RPTPs), antagonize RTK signaling by promoting adhesion over migration. In cancer, RTK signaling is constitutive due to mutated or amplified RTKs, which leads to growth factor independence, or autonomy. An alternative route for a tumor cell to achieve autonomy is to inactivate cell-cell CAMs such as RPTPs. RPTPs directly mediate cell adhesion and regulate both cadherin-dependent adhesion and signaling. In addition, RPTPs antagonize RTK signaling by dephosphorylating molecules activated following ligand binding. Both RPTPs and cadherins are downregulated in tumor cells by cleavage at the cell surface. This results in shedding of the extracellular, adhesive segment and displacement of the intracellular segment, altering its subcellular localization and access to substrates or binding partners. In this commentary we discuss the signals that are altered following RPTP and cadherin cleavage to promote cell migration. Tumor cells both step on the gas (RTKs) and disconnect the brakes (RPTPs and cadherins) during their invasive and metastatic journey.
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Affiliation(s)
- Polly J Phillips-Mason
- Department of Molecular Biology and Microbiology; School of Medicine; Case Western Reserve University; Cleveland, OH USA
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39
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Bahta M, Lountos GT, Dyas B, Kim SE, Ulrich RG, Waugh DS, Burke TR. Utilization of nitrophenylphosphates and oxime-based ligation for the development of nanomolar affinity inhibitors of the Yersinia pestis outer protein H (YopH) phosphatase. J Med Chem 2011; 54:2933-43. [PMID: 21443195 PMCID: PMC3085962 DOI: 10.1021/jm200022g] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Our current study reports the first K(M) optimization of a library of nitrophenylphosphate-containing substrates for generating an inhibitor lead against the Yersinia pestis outer protein phosphatase (YopH). A high activity substrate identified by this method (K(M) = 80 μM) was converted from a substrate into an inhibitor by replacement of its phosphate group with difluoromethylphosphonic acid and by attachment of an aminooxy handle for further structural optimization by oxime ligation. A cocrystal structure of this aminooxy-containing platform in complex with YopH allowed the identification of a conserved water molecule proximal to the aminooxy group that was subsequently employed for the design of furanyl-based oxime derivatives. By this process, a potent (IC(50) = 190 nM) and nonpromiscuous inhibitor was developed with good YopH selectivity relative to a panel of phosphatases. The inhibitor showed significant inhibition of intracellular Y. pestis replication at a noncytotoxic concentration. The current work presents general approaches to PTP inhibitor development that may be useful beyond YopH.
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Affiliation(s)
- Medhanit Bahta
- Chemical Biology Laboratory, Molecular Discovery Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
| | - George T. Lountos
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
| | - Beverly Dyas
- Laboratory of Molecular Immunology, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, U.S.A
| | - Sung-Eun Kim
- Chemical Biology Laboratory, Molecular Discovery Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
| | - Robert G. Ulrich
- Laboratory of Molecular Immunology, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, U.S.A
| | - David S. Waugh
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
| | - Terrence R. Burke
- Chemical Biology Laboratory, Molecular Discovery Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
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40
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Tan JCH, Kiland JA, Gonzalez JM, Gabelt BT, Peters DM, Kaufman PL. Sodium orthovanadate effect on outflow facility and intraocular pressure in live monkeys. Exp Eye Res 2010; 91:486-90. [PMID: 20620138 DOI: 10.1016/j.exer.2010.06.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2010] [Revised: 06/07/2010] [Accepted: 06/14/2010] [Indexed: 11/30/2022]
Abstract
Sodium orthovanadate (Na(3)VO(4)) is reported to reduce IOP by affecting aqueous formation, but whether it also affects outflow facility (OF) is unclear. We tested the effect of Na(3)VO(4) on OF and intraocular pressure (IOP) in live cynomolgus monkeys, and on actin and cell adhesion organization in cultured human trabecular meshwork (HTM) cells. Total OF (n = 12) was measured by 2-level constant pressure perfusion of the monkey anterior chamber (AC) before and after exchange with 1 mM Na(3)VO(4) or vehicle in opposite eyes. Topical 1% Na(3)VO(4) or vehicle only was given twice daily (each 2 × 20 μL drops) for 4 days to opposite eyes (n = 8), and Goldmann IOP was measured before and hourly after treatment for 6 h on Days 1 and 4. Filamentous actin and vinculin-containing cell adhesions were examined by epifluorescence microscopy after the cells had been incubated with 1 mM Na(3)VO(4) for 24 h. A) In monkeys, Na(3)VO(4) increased OF by 29.3 ± 8.8% (mean ± s.e.m.) over the perfusion interval when adjusted for baseline and contralateral eye washout (p = 0.01; n = 12). B) Day 1 baseline IOP was 16.2 ± 1.5 mmHg in treated eyes and 15.9 ± 1.3 mmHg in the contralateral control eyes. Following treatment on Day 1, IOP was no different (p > 0.05) between treated eyes and control eyes at any time-point or compared to baseline. Day 4 mean IOP averaged over hours 2-6 was 13.5 ± 0.8 mmHg in treated eyes and 16.1 ± 0.2 mmHg in control eyes. Treated eye IOP was lower than its Day 4 baseline (p < 0.005), lower than control eyes for the same Day 4 interval (p = 0.009), and lower than the Day 1 baseline (p = 0.0000). Control eye IOP on Day 4 was not significantly different from baseline on Day 1. C) Incubation of HTM cells with 1 mM Na(3)VO(4) for 24 h caused a loss of actin stress fibers and vinculin-containing adhesions. Cell retraction and separation was also observed in vanadate-treated cultures. Reformation of actin stress fibers, vinculin-containing adhesions and confluent monolayers occurred within 24 h after Na(3)VO(4)-containing culture medium was replaced with Na(3)VO(4)-free medium. Ocular administration of Na(3)VO(4) to live monkeys significantly increases OF and reduces IOP. Na(3)VO(4) reversibly disrupts actin and cell adhesion organization and causes retraction and separation of cultured HTM cells. Na(3)VO(4) increases pressure-dependent outflow in live monkeys. Altered actin architecture in the TM may play a part in this increased OF.
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Affiliation(s)
- James C H Tan
- Department of Ophthalmology, University of Southern California, Los Angeles, CA 90033, USA.
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Graham S, Ding M, Ding Y, Sours-Brothers S, Luchowski R, Gryczynski Z, Yorio T, Ma H, Ma R. Canonical transient receptor potential 6 (TRPC6), a redox-regulated cation channel. J Biol Chem 2010; 285:23466-76. [PMID: 20501650 PMCID: PMC2906337 DOI: 10.1074/jbc.m109.093500] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
This study examined the effect of H2O2 on the TRPC6 channel and its underlying mechanisms using a TRPC6 heterologous expression system. In TRPC6-expressing HEK293T cells, H2O2 significantly stimulated Ca2+ entry in a dose-dependent manner. Electrophysiological experiments showed that H2O2 significantly increased TRPC6 channel open probability and whole-cell currents. H2O2 also evoked a robust inward current in A7r5 vascular smooth muscle cells, which was nearly abolished by knockdown of TRPC6 using a small interfering RNA. Catalase substantially attenuated arginine vasopressin (AVP)-induced Ca2+ entry in cells co-transfected with TRPC6 and AVP V1 receptor. N-Ethylmaleimide and thimerosal were able to simulate the H2O2 response. Dithiothreitol or glutathione-reduced ethyl ester significantly antagonized the response. Furthermore, both N-ethylmaleimide- and H2O2-induced TRPC6 activations were only observed in the cell-attached patches but not in the inside-out patches. Moreover, 1-oleoyl-2-acetyl-sn-glycerol effect on TRPC6 was significantly greater in the presence of H2O2. Biotinylation assays revealed a significant increase in cell surface TRPC6 in response to H2O2. Similarly, in cells transfected with TRPC6-EGFP, confocal microscopy showed a significant increase in fluorescence intensity in the region of the cell membrane and adjacent to the membrane. AVP also increased the fluorescence intensity on the surface of the cells co-transfected with TRPC6-EGFP and V1 receptor, and this response was inhibited by catalase. These data indicate that H2O2 activates TRPC6 channels via modification of thiol groups of intracellular proteins. This cysteine oxidation-dependent pathway not only stimulates the TRPC6 channel by itself but also sensitizes the channels to diacylglycerol and promotes TRPC6 trafficking to the cell surface.
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Affiliation(s)
- Sarabeth Graham
- Department of Integrative Physiology and Cardiovascular Research Institute, University of North Texas Health Science Center, Fort Worth, Texas 76107, USA
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