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Rehman A, Alwutayd KM, Alshehri D, Alsudays IM, Azeem F, Rahman S, Abid M, Shah AA. Regulatory role of AGC genes in heat stress adaptation in maize ( Zea mays). FUNCTIONAL PLANT BIOLOGY : FPB 2024; 51:FP23282. [PMID: 38758970 DOI: 10.1071/fp23282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 04/19/2024] [Indexed: 05/19/2024]
Abstract
Heat stress represents a significant environmental challenge that restricts maize (Zea mays ) growth and yield on a global scale. Within the plant kingdom, the AGC gene family, encoding a group of protein kinases, has emerged as crucial players in various stress responses. Nevertheless, a comprehensive understanding of AGC genes in Z. mays under heat-stress conditions remains elusive. A genome-wide analysis was done using bioinformatics techniques to identify 39 AGC genes in Z. mays , categorising them into three subfamilies based on their conserved domains. We investigated their phylogenetic relationships, gene structures (including intron-exon configurations), and expression patterns. These genes are likely involved in diverse signalling pathways, fulfilling distinct roles when exposed to heat stress conditions. Notably, most ZmAGC1.5, ZmAGC1.9, ZmNDR3, ZmNDR5 and ZmIRE3 exhibited significant changes in expression levels under heat stress, featuring a high G-box ratio. Furthermore, we pinpointed a subset of AGC genes displaying highly coordinated expression, implying their potential involvement in the heat stress response pathway. Our study offers valuable insights into the contribution of AGC genes to Z. mays 's heat stress response, thus facilitating the development of heat-tolerant Z. mays varieties.
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Affiliation(s)
- Abdul Rehman
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Khairiah Mubarak Alwutayd
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Dikhnah Alshehri
- Department of Biology, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia
| | | | - Farrukh Azeem
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Shahroz Rahman
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Muhammad Abid
- Department of Plant Pathology, Bahauddin Zakariya University, Multan, Pakistan
| | - Asad Ali Shah
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
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Huang L, Wang Z, Wang F, Wang S, Wang D, Gao M, Li H, Song M, Zhang X. Triterpenoids from the Leaves of Diospyros digyna and Their PTP1B Inhibitory Activity. Molecules 2024; 29:1640. [PMID: 38611920 PMCID: PMC11013491 DOI: 10.3390/molecules29071640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/02/2024] [Accepted: 04/03/2024] [Indexed: 04/14/2024] Open
Abstract
Six new 2α-hydroxy ursane triterpenoids, 3α-cis-p-coumaroyloxy-2α,19α-dihydroxy-12-ursen-28-oic acid (1), 3α-trans-p-coumaroyloxy-2α,19α-dihydroxy-12-ursen-28-oic acid (2), 3α-trans-p-coumaroyloxy-2α-hydroxy-12-ursen-28-oic acid (3), 3β-trans-p-coumaroyloxy-2α-hydroxy-12,20(30)-ursadien-28-oic acid (4), 3β-trans-feruloyloxy-2α-hydroxy-12,20(30)-ursadien-28-oic acid (5), and 3α-trans-feruloyloxy-2α-hydroxy-12,20(30)-ursadien-28-oic acid (6), along with eleven known triterpenoids (7-17), were isolated from the leaves of Diospyros digyna. Their chemical structures were elucidated by comprehensive analysis of UV, IR, HRESIMS, and NMR spectra. All the isolated compounds were evaluated for their PTP1B inhibitory activity. 3β-O-trans-feruloyl-2α-hydroxy-urs-12-en-28-oic acid (13) showed the best inhibition activity with an IC50 value of 10.32 ± 1.21 μM. The molecular docking study found that the binding affinity of compound 13 for PTP1B was comparable to that of oleanolic acid (positive control).
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Affiliation(s)
- Lan Huang
- Guangdong Provincial Engineering Research Center for Modernization of TCM, Jinan University, Guangzhou 510632, China; (L.H.); (Z.W.); (F.W.); (S.W.); (D.W.); (M.S.)
- NMPA Key Laboratory for Quality Evaluation of TCM, Jinan University, Guangzhou 510632, China
| | - Ziqi Wang
- Guangdong Provincial Engineering Research Center for Modernization of TCM, Jinan University, Guangzhou 510632, China; (L.H.); (Z.W.); (F.W.); (S.W.); (D.W.); (M.S.)
- NMPA Key Laboratory for Quality Evaluation of TCM, Jinan University, Guangzhou 510632, China
- Guangdong Institute for Drug Control, Guangzhou 510663, China; (M.G.); (H.L.)
| | - Fangxin Wang
- Guangdong Provincial Engineering Research Center for Modernization of TCM, Jinan University, Guangzhou 510632, China; (L.H.); (Z.W.); (F.W.); (S.W.); (D.W.); (M.S.)
- NMPA Key Laboratory for Quality Evaluation of TCM, Jinan University, Guangzhou 510632, China
| | - Song Wang
- Guangdong Provincial Engineering Research Center for Modernization of TCM, Jinan University, Guangzhou 510632, China; (L.H.); (Z.W.); (F.W.); (S.W.); (D.W.); (M.S.)
- NMPA Key Laboratory for Quality Evaluation of TCM, Jinan University, Guangzhou 510632, China
| | - Dezhi Wang
- Guangdong Provincial Engineering Research Center for Modernization of TCM, Jinan University, Guangzhou 510632, China; (L.H.); (Z.W.); (F.W.); (S.W.); (D.W.); (M.S.)
- NMPA Key Laboratory for Quality Evaluation of TCM, Jinan University, Guangzhou 510632, China
| | - Meihua Gao
- Guangdong Institute for Drug Control, Guangzhou 510663, China; (M.G.); (H.L.)
| | - Hua Li
- Guangdong Institute for Drug Control, Guangzhou 510663, China; (M.G.); (H.L.)
| | - Min Song
- Guangdong Provincial Engineering Research Center for Modernization of TCM, Jinan University, Guangzhou 510632, China; (L.H.); (Z.W.); (F.W.); (S.W.); (D.W.); (M.S.)
- NMPA Key Laboratory for Quality Evaluation of TCM, Jinan University, Guangzhou 510632, China
| | - Xiaoqi Zhang
- Guangdong Provincial Engineering Research Center for Modernization of TCM, Jinan University, Guangzhou 510632, China; (L.H.); (Z.W.); (F.W.); (S.W.); (D.W.); (M.S.)
- NMPA Key Laboratory for Quality Evaluation of TCM, Jinan University, Guangzhou 510632, China
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3
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Liu S, Liu F, Zhang Z, Zhuang Z, Chen Y. PTPN2 inhibits the proliferation of psoriatic keratinocytes by dephosphorylation of STAT3. Cell Biochem Funct 2024; 42:e3947. [PMID: 38379221 DOI: 10.1002/cbf.3947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 01/16/2024] [Accepted: 01/17/2024] [Indexed: 02/22/2024]
Abstract
Psoriasis is a recurrent and protracted disease that severely impacts the patient's physical and mental health. Thus, there is an urgent need to explore its pathogenesis to identify therapeutic targets. The expression level of protein tyrosine phosphatase nonreceptor type 2 (PTPN2) was analyzed by immunohistochemistry techniques in psoriatic tissues and imiquimod-induced psoriatic mouse models. PTPN2 and signal transducer and activator of transcription 3 (STAT3) were overexpressed or silenced in human keratinocytes or an interleukin (IL)-6-induced psoriasis HaCaT cell model using overexpression plasmid transfection or small interfering RNA technology in vitro, and the effects of PTPN2 on STAT3, HaCaT cell function, and autophagy levels were investigated using reverse transcription-quantitative polymerase chain reaction, Western blot, Cell Counting Kit 8, 5-ethynyl-20-deoxyuridine, flow cytometry, and transmission electron microscopy. PTPN2 expression was found to be significantly downregulated in psoriatic tissues. Then, the in vitro antipsoriatic properties of PTPN2 were investigated in an IL-6-induced psoriasis-like cell model, and the results demonstrated that inhibition of keratinocyte proliferation by PTPN2 may be associated with elevated STAT3 dephosphorylation and autophagy levels. These findings provide novel insights into the mechanisms of autophagy in psoriatic keratinocytes and may be essential for developing new therapeutic strategies to improve inflammatory homeostasis in psoriatic patients.
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Affiliation(s)
- Shougang Liu
- Department of Dermatology, Dermatology Hospital of Southern Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Fanghua Liu
- Department of Dermatology, Guangdong Medical University, Zhanjiang, Guangdong, People's Republic of China
- Department of Dermatology, Ganzhou Municipal Hospital, Ganzhou, Jiangxi, People's Republic of China
| | - Zeqiao Zhang
- Department of Dermatology, Dermatology Hospital of Southern Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Zhe Zhuang
- Department of Dermatology, Guangdong Medical University, Zhanjiang, Guangdong, People's Republic of China
| | - Yongfeng Chen
- Department of Dermatology, Dermatology Hospital of Southern Medical University, Guangzhou, Guangdong, People's Republic of China
- Department of Dermatology, Guangdong Medical University, Zhanjiang, Guangdong, People's Republic of China
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Burroughs A, Aravind L. New biochemistry in the Rhodanese-phosphatase superfamily: emerging roles in diverse metabolic processes, nucleic acid modifications, and biological conflicts. NAR Genom Bioinform 2023; 5:lqad029. [PMID: 36968430 PMCID: PMC10034599 DOI: 10.1093/nargab/lqad029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/10/2023] [Accepted: 03/09/2023] [Indexed: 03/25/2023] Open
Abstract
The protein-tyrosine/dual-specificity phosphatases and rhodanese domains constitute a sprawling superfamily of Rossmannoid domains that use a conserved active site with a cysteine to catalyze a range of phosphate-transfer, thiotransfer, selenotransfer and redox activities. While these enzymes have been extensively studied in the context of protein/lipid head group dephosphorylation and various thiotransfer reactions, their overall diversity and catalytic potential remain poorly understood. Using comparative genomics and sequence/structure analysis, we comprehensively investigate and develop a natural classification for this superfamily. As a result, we identified several novel clades, both those which retain the catalytic cysteine and those where a distinct active site has emerged in the same location (e.g. diphthine synthase-like methylases and RNA 2' OH ribosyl phosphate transferases). We also present evidence that the superfamily has a wider range of catalytic capabilities than previously known, including a set of parallel activities operating on various sugar/sugar alcohol groups in the context of NAD+-derivatives and RNA termini, and potential phosphate transfer activities involving sugars and nucleotides. We show that such activities are particularly expanded in the RapZ-C-DUF488-DUF4326 clade, defined here for the first time. Some enzymes from this clade are predicted to catalyze novel DNA-end processing activities as part of nucleic-acid-modifying systems that are likely to function in biological conflicts between viruses and their hosts.
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Affiliation(s)
- A Maxwell Burroughs
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - L Aravind
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
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Gu SH, Chen CH, Chang CH, Lin PL. Expression of tyrosine phosphatases in relation to PTTH-stimulated ecdysteroidogenesis in prothoracic glands of the silkworm, Bombyx mori. Gen Comp Endocrinol 2023; 331:114165. [PMID: 36368438 DOI: 10.1016/j.ygcen.2022.114165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 10/19/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022]
Abstract
Protein tyrosine phosphorylation is a reversible, dynamic process regulated by the activities of tyrosine kinases and tyrosine phosphatases. Although the involvement of tyrosine kinases in the prothoracicotropic hormone (PTTH)-stimulated ecdysteroidogenesis in insect prothoracic glands (PGs) has been documented, few studies have been conducted on the involvement of protein tyrosine phosphatases (PTPs) in PTTH-stimulated ecdysteroidogenesis. In the present study, we investigated the correlation between PTPs and PTTH-stimulated ecdysteroidogenesis in Bombyx mori PGs. Our results showed that the basal PTP enzymatic activities exhibited development-specific changes during the last larval instar and pupation stage, with high activities being detected during the later stages of the last larval instar. PTP enzymatic activity was stimulated by PTTH treatment both in vitro and in vivo. Pretreatment with phenylarsine oxide (PAO) and benzylphosphonic acid (BPA), two chemical inhibitors of tyrosine phosphatase, reduced PTTH-stimulated enzymatic activity. Determination of ecdysteroid secretion showed that treatment with PAO and BPA did not affect basal ecdysteroid secretion, but greatly inhibited PTTH-stimulated ecdysteroid secretion, indicating that PTTH-stimulated PTP activity is indeed involved in ecdysteroid secretion. PTTH-stimulated phosphorylation of the extracellular signal-regulated kinase (ERK) and 4E-binding protein (4E-BP) was partially inhibited by pretreatment with either PAO or BPA, indicating the potential link between PTPs and phosphorylation of ERK and 4E-BP. In addition, we also found that in vitro treatment with 20-hydroxyecdysone did not affect PTP enzymatic activity. We further investigated the expressions of two important PTPs (PTP 1B (PTP1B) and the phosphatase and tension homologue (PTEN)) in Bombyx PGs. Our immunoblotting analysis showed that B. mori PGs contained the proteins of PTP1B and PTEN, with PTP1B protein undergoing development-specific changes. Protein levels of PTP1B and PTEN were not affected by PTTH treatment. The gene expression levels of PTP1B and PTEN showed development-specific changes. From these results, we suggest that PTTH-regulated PTP signaling may crosstalk with ERK and target of rapamycin (TOR) signaling pathways and is a necessary component for stimulation of ecdysteroid secretion.
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Affiliation(s)
- Shi-Hong Gu
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC.
| | - Chien-Hung Chen
- Chung Hwa University of Medical Technology, 89 Wen-Hwa 1st Road, Jen-Te Township, Tainan County 717, Taiwan, ROC
| | - Chia-Hao Chang
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC
| | - Pei-Ling Lin
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC
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6
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Im ST, Kim HS, Jung WK, Lee SH. Ishophloroglucin A, a potent PTP1B inhibitor isolated from brown alga Ishige okamurae inhibits adipogenesis in 3T3-L1 adipocytes. Fitoterapia 2022; 163:105342. [PMID: 36330897 DOI: 10.1016/j.fitote.2022.105342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/23/2022] [Accepted: 10/23/2022] [Indexed: 11/28/2022]
Abstract
Ishophloroglucin A (IPA) is one of the most abundant and active compounds in Ishige okamurae and is known to be a potential therapeutic candidate for the improvement of metabolic diseases. However, IPA on the inhibitory effects of protein tyrosine phosphatase 1B (PTP1B) and adipogenesis have not been determined. In this study, we investigated the effects of IPA on the inhibition of PTP1B, the effects on adipogenesis, and its mechanisms of action in 3 T3-L1 adipocytes. The IC50 value of IPA against PTP1B was 0.43 μM, which evidenced the higher inhibition activity than that of ursolic acid, a known PTP1B inhibitor. For further insight, we predicted the 3D structure of PTP1B and used a docking algorithm to simulate the binding between PTP1B and IPA. Molecular docking studies revealed a high and stable binding affinity between IPA and PTP1B and indicated that the IPA could interacts with the amino acid residues located in a region to the active site of PTP1B. Further studies showed that IPA concentrations between 6.25 μM and 25 μM dose-dependently attenuated adipogenesis, which was accompanied by a reduction in adipogenesis-related factors, including PPARγ, C/EBPα, SREBP-1c, and FABP4. Our findings suggested that IPA may be a promising natural compound for the treatment of obesity and related diseases.
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Affiliation(s)
- Seung Tae Im
- Department of Medical Science, Soonchunhyang University, Asan 31538, Republic of Korea
| | - Hyun-Soo Kim
- National Marine Biodiversity Institute of Korea, Seocheon 33662, Republic of Korea
| | - Won-Kyo Jung
- Major of Biomedical Engineering, Division of Smart Healthcare and New-senior Healthcare Innovation Center (BK21 Plus), Pukyong National University, Busan 48513, Republic of Korea; Research Center for Marine-Integrated Bionics Technology and Marine Integrated Biomedical Technology Center, Pukyong National University, Busan 48513, Republic of Korea.
| | - Seung-Hong Lee
- Department of Medical Science, Soonchunhyang University, Asan 31538, Republic of Korea; Department of Pharmaceutical Engineering, Soonchunhyang University, Asan 31538, Republic of Korea.
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Teimouri M, Hosseini H, ArabSadeghabadi Z, Babaei-Khorzoughi R, Gorgani-Firuzjaee S, Meshkani R. The role of protein tyrosine phosphatase 1B (PTP1B) in the pathogenesis of type 2 diabetes mellitus and its complications. J Physiol Biochem 2022; 78:307-322. [PMID: 34988903 DOI: 10.1007/s13105-021-00860-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 11/16/2021] [Indexed: 01/16/2023]
Abstract
Insulin resistance, the most important characteristic of the type 2 diabetes mellitus (T2DM), is mostly caused by impairment in the insulin receptor (IR) signal transduction pathway. Protein tyrosine phosphatase 1B (PTP1B), one of the main negative regulators of the IR signaling pathway, is broadly expressed in various cells and tissues. PTP1B decreases the phosphorylation of the IR resulting in insulin resistance in various tissues. The evidence for the physiological role of PTP1B in regulation of metabolic pathways came from whole-body PTP1B-knockout mice. Whole-body and tissue-specific PTP1B-knockout mice showed improvement in adiposity, insulin resistance, and glucose tolerance. In addition, the key role of PTP1B in the pathogenesis of T2DM and its complications was further investigated in mice models of PTP1B deficient/overexpression. In recent years, targeting PTP1B using PTP1B inhibitors is being considered an attractive target to treat T2DM. PTP1B inhibitors improve the sensitivity of the insulin receptor and have the ability to cure insulin resistance-related diseases. We herein summarized the biological functions of PTP1B in different tissues in vivo and in vitro. We also describe the effectiveness of potent PTP1B inhibitors as pharmaceutical agents to treat T2DM.
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Affiliation(s)
- Maryam Teimouri
- Department of Clinical Biochemistry, School of Allied Medical Sciences, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Hossein Hosseini
- Department of Clinical Biochemistry, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Zahra ArabSadeghabadi
- Department of Clinical Sciences, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran
| | - Reyhaneh Babaei-Khorzoughi
- Department of Clinical Biochemistry, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Sattar Gorgani-Firuzjaee
- Department of Medical Laboratory Sciences, School of Allied Health Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Reza Meshkani
- Department of Clinical Biochemistry, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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A Novel PTP1B Inhibitor-Phosphate of Polymannuronic Acid Ameliorates Insulin Resistance by Regulating IRS-1/Akt Signaling. Int J Mol Sci 2021; 22:ijms222312693. [PMID: 34884501 PMCID: PMC8657924 DOI: 10.3390/ijms222312693] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/21/2021] [Accepted: 11/21/2021] [Indexed: 02/06/2023] Open
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a critical negative modulator of insulin signaling and has attracted considerable attention in treating type 2 diabetes mellitus (T2DM). Low-molecular-weight polymannuronic acid phosphate (LPMP) was found to be a selective PTP1B inhibitor with an IC50 of 1.02 ± 0.17 μM. Cellular glucose consumption was significantly elevated in insulin-resistant HepG2 cells after LPMP treatment. LPMP could alleviate oxidative stress and endoplasmic reticulum stress, which are associated with the development of insulin resistance. Western blot and polymerase chain reaction (PCR) analysis demonstrated that LPMP could enhance insulin sensitivity through the PTP1B/IRS/Akt transduction pathway. Furthermore, animal study confirmed that LPMP could decrease blood glucose, alleviate insulin resistance, and exert hepatoprotective effects in diabetic mice. Taken together, LPMP can effectively inhibit insulin resistance and has high potential as an anti-diabetic drug candidate to be further developed.
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Gu SH, Chen CH, Lin PL. Expression of protein tyrosine phosphatases and Bombyx embryonic development. JOURNAL OF INSECT PHYSIOLOGY 2021; 130:104198. [PMID: 33549567 DOI: 10.1016/j.jinsphys.2021.104198] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 11/25/2020] [Accepted: 01/28/2021] [Indexed: 06/12/2023]
Abstract
Protein phosphorylation is an integral component of signal transduction pathways within eukaryotic cells, and it is regulated by coordinated interactions between protein kinases and protein phosphatases. Our previous study demonstrated differential expressions of serine/threonine protein phosphatases (PP2A and calcineurin) between diapause and developing eggs in Bombyx mori. In the present study, we further investigated expression of protein tyrosine phosphatases (PTPs) in relation to the Bombyx embryonic development. An immunoblot analysis showed that eggs contained the proteins of the 51-kDa PTP 1B (PTP1B), the 55-kDa phosphatase and tensin homologue (PTEN), and the 70-kDa Src homology 2 (SH2) domain-containing phosphatase 2 (SHP2), which undergo differential changes between diapause and developing eggs. Protein level of PTP1B and PTEN in eggs whose diapause initiation was prevented by HCl gradually increased toward embryonic development. The protein level of SHP2 also showed a dramatic increase on days 7 and 8 after HCl treatment. However, protein levels of PTP1B, PTEN, and SHP2 in diapause eggs remained at low levels during the first 9 days after oviposition. These differential changing patterns in protein levels were further confirmed using both non-diapause eggs and eggs in which diapause had been terminated by chilling of diapausing eggs at 5 °C for 70 days and then were transferred to 25 °C. Direct determination of PTP enzymatic activities showed higher activities in developing eggs (HCl-treated eggs, non-diapause eggs, and chilled eggs) compared to those in diapause eggs. Examination of temporal changes in mRNA expression levels of PTP1B, PTEN, and SHP2 did not show significant differences between diapause eggs and HCl-treated eggs except high expression in SHP2 variant B during the later embryonic development in HCl-treated eggs. These results demonstrate that higher protein levels of PTP1B, PTEN, and SHP2 and increased tyrosine phosphatase enzymatic activities in developing eggs are likely related to embryonic development of B. mori.
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Affiliation(s)
- Shi-Hong Gu
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC.
| | - Chien-Hung Chen
- Chung Hwa University of Medical Technology, 89 Wen-Hwa 1st Road, Jen-Te Township, Tainan County 717, Taiwan, ROC
| | - Pei-Ling Lin
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC
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Puckett DL, Alquraishi M, Chowanadisai W, Bettaieb A. The Role of PKM2 in Metabolic Reprogramming: Insights into the Regulatory Roles of Non-Coding RNAs. Int J Mol Sci 2021; 22:1171. [PMID: 33503959 PMCID: PMC7865720 DOI: 10.3390/ijms22031171] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/13/2021] [Accepted: 01/14/2021] [Indexed: 01/17/2023] Open
Abstract
Pyruvate kinase is a key regulator in glycolysis through the conversion of phosphoenolpyruvate (PEP) into pyruvate. Pyruvate kinase exists in various isoforms that can exhibit diverse biological functions and outcomes. The pyruvate kinase isoenzyme type M2 (PKM2) controls cell progression and survival through the regulation of key signaling pathways. In cancer cells, the dimer form of PKM2 predominates and plays an integral role in cancer metabolism. This predominance of the inactive dimeric form promotes the accumulation of phosphometabolites, allowing cancer cells to engage in high levels of synthetic processing to enhance their proliferative capacity. PKM2 has been recognized for its role in regulating gene expression and transcription factors critical for health and disease. This role enables PKM2 to exert profound regulatory effects that promote cancer cell metabolism, proliferation, and migration. In addition to its role in cancer, PKM2 regulates aspects essential to cellular homeostasis in non-cancer tissues and, in some cases, promotes tissue-specific pathways in health and diseases. In pursuit of understanding the diverse tissue-specific roles of PKM2, investigations targeting tissues such as the kidney, liver, adipose, and pancreas have been conducted. Findings from these studies enhance our understanding of PKM2 functions in various diseases beyond cancer. Therefore, there is substantial interest in PKM2 modulation as a potential therapeutic target for the treatment of multiple conditions. Indeed, a vast plethora of research has focused on identifying therapeutic strategies for targeting PKM2. Recently, targeting PKM2 through its regulatory microRNAs, long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) has gathered increasing interest. Thus, the goal of this review is to highlight recent advancements in PKM2 research, with a focus on PKM2 regulatory microRNAs and lncRNAs and their subsequent physiological significance.
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Affiliation(s)
- Dexter L. Puckett
- Department of Nutrition, University of Tennessee Knoxville, Knoxville, TN 37996, USA; (D.L.P.); (M.A.)
| | - Mohammed Alquraishi
- Department of Nutrition, University of Tennessee Knoxville, Knoxville, TN 37996, USA; (D.L.P.); (M.A.)
| | - Winyoo Chowanadisai
- Department of Nutrition, Oklahoma State University, Stillwater, OK 74078, USA;
| | - Ahmed Bettaieb
- Department of Nutrition, University of Tennessee Knoxville, Knoxville, TN 37996, USA; (D.L.P.); (M.A.)
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PRL-2 phosphatase is required for vascular morphogenesis and angiogenic signaling. Commun Biol 2020; 3:603. [PMID: 33097786 PMCID: PMC7584612 DOI: 10.1038/s42003-020-01343-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 09/30/2020] [Indexed: 12/21/2022] Open
Abstract
Protein tyrosine phosphatases are essential modulators of angiogenesis and have been identified as novel therapeutic targets in cancer and anti-angiogenesis. The roles of atypical Phosphatase of Regenerative Liver (PRL) phosphatases in this context remain poorly understood. Here, we investigate the biological function of PRL phosphatases in developmental angiogenesis in the postnatal mouse retina and in cell culture. We show that endothelial cells in the retina express PRL-2 encoded by the Ptp4a2 gene, and that inducible endothelial and global Ptp4a2 mutant mice exhibit defective retinal vascular outgrowth, arteriovenous differentiation, and sprouting angiogenesis. Mechanistically, PTP4A2 deletion limits angiogenesis by inhibiting endothelial cell migration and the VEGF-A, DLL-4/NOTCH-1 signaling pathway. This study reveals the importance of PRL-2 as a modulator of vascular development.
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12
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Giagulli C, Caccuri F, Zorzan S, Bugatti A, Zani A, Filippini F, Manocha E, D'Ursi P, Orro A, Dolcetti R, Caruso A. B-cell clonogenic activity of HIV-1 p17 variants is driven by PAR1-mediated EGF transactivation. Cancer Gene Ther 2020; 28:649-666. [PMID: 33093643 PMCID: PMC8203498 DOI: 10.1038/s41417-020-00246-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/30/2020] [Accepted: 10/08/2020] [Indexed: 11/29/2022]
Abstract
Combined antiretroviral therapy (cART) for HIV-1 dramatically slows disease progression among HIV+ individuals. Currently, lymphoma represents the main cause of death among HIV-1-infected patients. Detection of p17 variants (vp17s) endowed with B-cell clonogenic activity in HIV-1-seropositive patients with lymphoma suggests their possible role in lymphomagenesis. Here, we demonstrate that the clonogenic activity of vp17s is mediated by their binding to PAR1 and to PAR1-mediated EGFR transactivation through Gq protein. The entire vp17s-triggered clonogenic process is MMPs dependent. Moreover, phosphoproteomic and bioinformatic analysis highlighted the crucial role of EGFR/PI3K/Akt pathway in modulating several molecules promoting cancer progression, including RAC1, ABL1, p53, CDK1, NPM, Rb, PTP-1B, and STAT1. Finally, we show that a peptide (F1) corresponding to the vp17s functional epitope is sufficient to trigger the PAR1/EGFR/PI3K/Akt pathway and bind PAR1. Our findings suggest novel potential therapeutic targets to counteract vp17-driven lymphomagenesis in HIV+ patients.
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Affiliation(s)
- Cinzia Giagulli
- Section of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy
| | - Francesca Caccuri
- Section of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy
| | - Simone Zorzan
- Plantech, Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science & Technology (LIST), L-4422, Belvaux, Luxembourg
| | - Antonella Bugatti
- Section of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy
| | - Alberto Zani
- Section of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy
| | - Federica Filippini
- Section of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy
| | - Ekta Manocha
- Section of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy
| | - Pasqualina D'Ursi
- Department of Biomedical Sciences, Institute for Biomedical Technologies e National Research Council (ITB-CNR), 20090, Segrate (MI), Italy
| | - Alessandro Orro
- Department of Biomedical Sciences, Institute for Biomedical Technologies e National Research Council (ITB-CNR), 20090, Segrate (MI), Italy
| | - Riccardo Dolcetti
- University of Queensland Diamantina Institute, Translational Research Institute, University of Queensland, Brisbane, QLD, Australia.,Cancer Bio-Immunotherapy Unit, Centro di Riferimento Oncologico - IRCCS, Aviano, Italy
| | - Arnaldo Caruso
- Section of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy.
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13
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Pardella E, Pranzini E, Leo A, Taddei ML, Paoli P, Raugei G. Oncogenic Tyrosine Phosphatases: Novel Therapeutic Targets for Melanoma Treatment. Cancers (Basel) 2020; 12:E2799. [PMID: 33003469 PMCID: PMC7599540 DOI: 10.3390/cancers12102799] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/24/2020] [Accepted: 09/28/2020] [Indexed: 12/12/2022] Open
Abstract
Despite a large number of therapeutic options available, malignant melanoma remains a highly fatal disease, especially in its metastatic forms. The oncogenic role of protein tyrosine phosphatases (PTPs) is becoming increasingly clear, paving the way for novel antitumor treatments based on their inhibition. In this review, we present the oncogenic PTPs contributing to melanoma progression and we provide, where available, a description of new inhibitory strategies designed against these enzymes and possibly useful in melanoma treatment. Considering the relevance of the immune infiltrate in supporting melanoma progression, we also focus on the role of PTPs in modulating immune cell activity, identifying interesting therapeutic options that may support the currently applied immunomodulating approaches. Collectively, this information highlights the value of going further in the development of new strategies targeting oncogenic PTPs to improve the efficacy of melanoma treatment.
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Affiliation(s)
- Elisa Pardella
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio” University of Florence, Viale Morgagni 50, 50134 Florence, Italy; (E.P.); (E.P.); (A.L.); (G.R.)
| | - Erica Pranzini
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio” University of Florence, Viale Morgagni 50, 50134 Florence, Italy; (E.P.); (E.P.); (A.L.); (G.R.)
| | - Angela Leo
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio” University of Florence, Viale Morgagni 50, 50134 Florence, Italy; (E.P.); (E.P.); (A.L.); (G.R.)
| | - Maria Letizia Taddei
- Department of Experimental and Clinical Medicine, University of Florence, Viale Morgagni 50, 50134 Florence, Italy;
| | - Paolo Paoli
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio” University of Florence, Viale Morgagni 50, 50134 Florence, Italy; (E.P.); (E.P.); (A.L.); (G.R.)
| | - Giovanni Raugei
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio” University of Florence, Viale Morgagni 50, 50134 Florence, Italy; (E.P.); (E.P.); (A.L.); (G.R.)
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14
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Chemically Diverse and Biologically Active Secondary Metabolites from Marine Phylum chlorophyta. Mar Drugs 2020; 18:md18100493. [PMID: 32993146 PMCID: PMC7601752 DOI: 10.3390/md18100493] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/24/2020] [Accepted: 09/24/2020] [Indexed: 02/06/2023] Open
Abstract
For a long time, algal chemistry from terrestrial to marine or freshwater bodies, especially chlorophytes, has fascinated numerous investigators to develop new drugs in the nutraceutical and pharmaceutical industries. As such, chlorophytes comprise a diverse structural class of secondary metabolites, having functional groups that are specific to a particular source. All bioactive compounds of chlorophyte are of great interest due to their supplemental/nutritional/pharmacological activities. In this review, a detailed description of the chemical diversity of compounds encompassing alkaloids, terpenes, steroids, fatty acids and glycerides, their subclasses and their structures are discussed. These promising natural products have efficiency in developing new drugs necessary in the treatment of various deadly pathologies (cancer, HIV, SARS-CoV-2, several inflammations, etc.). Marine chlorophyte, therefore, is portrayed as a pivotal treasure in the case of drugs having marine provenience. It is a domain of research expected to probe novel pharmaceutically or nutraceutically important secondary metabolites resulting from marine Chlorophyta. In this regard, our review aims to compile the isolated secondary metabolites having diverse chemical structures from chlorophytes (like Caulerpa ssp., Ulva ssp., Tydemania ssp., Penicillus ssp., Codium ssp., Capsosiphon ssp., Avrainvillea ssp.), their biological properties, applications and possible mode of action.
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15
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Kousaxidis A, Petrou A, Lavrentaki V, Fesatidou M, Nicolaou I, Geronikaki A. Aldose reductase and protein tyrosine phosphatase 1B inhibitors as a promising therapeutic approach for diabetes mellitus. Eur J Med Chem 2020; 207:112742. [PMID: 32871344 DOI: 10.1016/j.ejmech.2020.112742] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 08/06/2020] [Indexed: 02/07/2023]
Abstract
Diabetes mellitus is a metabolic disease characterized by high blood glucose levels and usually associated with several chronic pathologies. Aldose reductase and protein tyrosine phosphatase 1B enzymes have identified as two novel molecular targets associated with the onset and progression of type II diabetes and related comorbidities. Although many inhibitors against these enzymes have already found in the field of diabetic mellitus, the research for discovering more effective and selective agents with optimal pharmacokinetic properties continues. In addition, dual inhibition of these target proteins has proved as a promising therapeutic approach. A variety of diverse scaffolds are presented in this review for the future design of potent and selective inhibitors of aldose reductase and protein tyrosine phosphatase 1B based on the most important structural features of both enzymes. The discovery of novel dual aldose reductase and protein tyrosine phosphatase 1B inhibitors could be effective therapeutic molecules for the treatment of insulin-resistant type II diabetes mellitus. The methods used comprise a literature survey and X-ray crystal structures derived from Protein Databank (PDB). Despite the available therapeutic options for type II diabetes mellitus, the inhibitors of aldose reductase and protein tyrosine phosphatase 1B could be two promising approaches for the effective treatment of hyperglycemia and diabetes-associated pathologies. Due to the poor pharmacokinetic profile and low in vivo efficacy of existing inhibitors of both targets, the research turned to more selective and cell-permeable agents as well as multi-target molecules.
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Affiliation(s)
- Antonios Kousaxidis
- School of Health, Department of Pharmacy, Aristotle University of Thessaloniki, 54124, Greece
| | - Anthi Petrou
- School of Health, Department of Pharmacy, Aristotle University of Thessaloniki, 54124, Greece
| | - Vasiliki Lavrentaki
- School of Health, Department of Pharmacy, Aristotle University of Thessaloniki, 54124, Greece
| | - Maria Fesatidou
- School of Health, Department of Pharmacy, Aristotle University of Thessaloniki, 54124, Greece
| | - Ioannis Nicolaou
- School of Health, Department of Pharmacy, Aristotle University of Thessaloniki, 54124, Greece
| | - Athina Geronikaki
- School of Health, Department of Pharmacy, Aristotle University of Thessaloniki, 54124, Greece.
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16
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Kim M, Morales LD, Lee CJ, Olivarez SA, Kim WJ, Hernandez J, Mummidi S, Jenkinson C, Tsin AT, Jang IS, Slaga TJ, Kim DJ. Overexpression of TC-PTP in murine epidermis attenuates skin tumor formation. Oncogene 2020; 39:4241-4256. [PMID: 32286519 PMCID: PMC7244373 DOI: 10.1038/s41388-020-1282-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 03/18/2020] [Accepted: 03/23/2020] [Indexed: 02/07/2023]
Abstract
T-cell protein tyrosine phosphatase (TC-PTP), encoded by Ptpn2, has been shown to function as a tumor suppressor during skin carcinogenesis. In the current study, we generated a novel epidermal-specific TC-PTP-overexpressing (K5HA.Ptpn2) mouse model to show that TC-PTP contributes to the attenuation of chemically induced skin carcinogenesis through the synergistic regulation of STAT1, STAT3, STAT5, and PI3K/AKT signaling. We found overexpression of TC-PTP increased epidermal sensitivity to DMBA-induced apoptosis and it decreased TPA-mediated hyperproliferation, coinciding with reduced epidermal thickness. Inhibition of STAT1, STAT3, STAT5, or AKT reversed the effects of TC-PTP overexpression on epidermal survival and proliferation. Mice overexpressing TC-PTP in the epidermis developed significantly reduced numbers of tumors during skin carcinogenesis and presented a prolonged latency of tumor initiation. Examination of human papillomas and squamous cell carcinomas (SCCs) revealed that TC-PTP expression was significantly reduced and TC-PTP expression was inversely correlated with the increased grade of SCCs. Our findings demonstrate that TC-PTP is a potential therapeutic target for the prevention of human skin cancer given that it is a major negative regulator of oncogenic signaling.
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Affiliation(s)
- Mihwa Kim
- Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Liza D Morales
- Department of Human Genetics, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Cheol Jung Lee
- Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Serena A Olivarez
- Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Woo Jin Kim
- School of Mathematical and Statistical Sciences, College of Sciences, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Joselin Hernandez
- Department of Human Genetics, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Srinivas Mummidi
- Department of Human Genetics, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Christopher Jenkinson
- Department of Human Genetics, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Andrew T Tsin
- Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Ik-Soon Jang
- Division of Bioconvergence Analysis, Korea Basic Science Institute, Daejeon, 305-333, Republic of Korea
| | - Thomas J Slaga
- Department of Pharmacology, School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Dae Joon Kim
- Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA.
- Department of Human Genetics, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA.
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17
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PTPN1/2-mediated dephosphorylation of MITA/STING promotes its 20S proteasomal degradation and attenuates innate antiviral response. Proc Natl Acad Sci U S A 2019; 116:20063-20069. [PMID: 31527250 DOI: 10.1073/pnas.1906431116] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Upon cytosolic viral DNA stimulation, cGMP-AMP synthase (cGAS) catalyzes synthesis of 2'3'cGMP-AMP (cGAMP), which binds to the adaptor protein MITA (mediator of IRF3 activation, also called STING, stimulator of IFN genes) and induces innate antiviral response. How the activity of MITA/STING is regulated to avoid excessive innate immune response is not fully understood. Here we identified the tyrosine-protein phosphatase nonreceptor type (PTPN) 1 and 2 as MITA/STING-associated proteins. PTPN1 and PTPN2 are associated with MITA/STING following viral infection and dephosphorylate MITA/STING at Y245. Dephosphorylation of MITA/STING leads to its degradation via the ubiquitin-independent 20S proteasomal pathway, which is dependent on the intrinsically disordered region (IDR) of MITA/STING. Deficiencies of PTPN1 and PTPN2 enhance viral DNA-induced transcription of downstream antiviral genes and innate antiviral response. Our findings reveal that PTPN1/2-mediated dephosphorylation of MITA/STING and its degradation by the 20S proteasomal pathway is an important regulatory mechanism of innate immune response to DNA virus.
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18
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Morales LD, Archbold AK, Olivarez S, Slaga TJ, DiGiovanni J, Kim DJ. The role of T-cell protein tyrosine phosphatase in epithelial carcinogenesis. Mol Carcinog 2019; 58:1640-1647. [PMID: 31264291 DOI: 10.1002/mc.23078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 06/04/2019] [Accepted: 06/05/2019] [Indexed: 02/06/2023]
Abstract
T-cell protein tyrosine phosphatase (TC-PTP, encoded by PTPN2) is a nonreceptor PTP that is most highly expressed in hematopoietic tissues. TC-PTP modulates a variety of physiological functions including cell cycle progression, cell survival and proliferation, and hematopoiesis through tyrosine dephosphorylation of its target substrates, such as EGFR, JAK1, JAK3, STAT1, and STAT3. Studies with whole or tissue-specific loss of TC-PTP function transgenic mice have shown that TC-PTP has crucial roles in the regulation of the immune response, insulin signaling, and oncogenic signaling. More recently, the generation of epidermal-specific TC-PTP-deficient mice for use in multistage skin carcinogenesis bioassays demonstrated that TC-PTP suppresses skin tumor formation by negatively regulating STAT3 and AKT signaling. Further investigation showed that TC-PTP also minimizes UVB-induced epidermal cell damage by promoting apoptosis through the negative regulation of Flk-1/JNK signaling. These findings provide major evidence for a tumor suppressive function for TC-PTP against environment-induced skin cancer. Here, we will discuss TC-PTP, its substrates, and its functions with an emphasis on its role in skin carcinogenesis.
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Affiliation(s)
- Liza D Morales
- Department of Human Genetics, School of Medicine, University of Texas Rio Grande Valley, Edinburg, Texas
| | - Anna K Archbold
- Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, Texas
| | - Serena Olivarez
- Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, Texas
| | - Thomas J Slaga
- Department of Pharmacology, School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - John DiGiovanni
- Division of Pharmacology & Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas
| | - Dae Joon Kim
- Department of Human Genetics, School of Medicine, University of Texas Rio Grande Valley, Edinburg, Texas.,Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, Texas
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19
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Benomar Y, Taouis M. Molecular Mechanisms Underlying Obesity-Induced Hypothalamic Inflammation and Insulin Resistance: Pivotal Role of Resistin/TLR4 Pathways. Front Endocrinol (Lausanne) 2019; 10:140. [PMID: 30906281 PMCID: PMC6418006 DOI: 10.3389/fendo.2019.00140] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 02/15/2019] [Indexed: 12/16/2022] Open
Abstract
Low-grade inflammation and insulin resistance are among the clinical features of obesity that are thought to promote the progressive onset of type 2 diabetes. However, the underlying mechanisms linking these disorders remain not fully understood. Recent reports pointed out hypothalamic inflammation as a major step in the onset of obesity-induced insulin resistance. In light of the increasing prevalence of obesity and T2D, two worldwide public health concerns, deciphering mechanisms implicated in hypothalamic inflammation constitutes a major challenge in the field of insulin-resistance/obesity. Several clinical and experimental studies have identified resistin as a key hormone linking insulin-resistance to obesity, notably through the activation of Toll Like Receptor (TLR) 4 signaling pathways. In this review, we present an overview of the molecular mechanisms underlying obesity-induced hypothalamic inflammation and insulin resistance with peculiar focus on the role of resistin/TLR4 signaling pathway.
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20
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Ezzat SM, Bishbishy MHE, Habtemariam S, Salehi B, Sharifi-Rad M, Martins N, Sharifi-Rad J. Looking at Marine-Derived Bioactive Molecules as Upcoming Anti-Diabetic Agents: A Special Emphasis on PTP1B Inhibitors. Molecules 2018; 23:E3334. [PMID: 30558294 PMCID: PMC6321226 DOI: 10.3390/molecules23123334] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 12/10/2018] [Accepted: 12/13/2018] [Indexed: 12/03/2022] Open
Abstract
Diabetes mellitus (DM) is a chronic metabolic disease with high morbimortality rates. DM has two types: type 1, which is often associated with a total destruction of pancreatic beta cells, and non-insulin-dependent or type 2 diabetes mellitus (T2DM), more closely associated with obesity and old age. The main causes of T2DM are insulin resistance and/or inadequate insulin secretion. Protein-tyrosine phosphatase 1B (PTP1B) negatively regulates insulin signaling pathways and plays an important role in T2DM, as its overexpression may induce insulin resistance. Thus, since PTP1B may be a therapeutic target for both T2DM and obesity, the search for novel and promising natural inhibitors has gained much attention. Hence, several marine organisms, including macro and microalgae, sponges, marine invertebrates, sea urchins, seaweeds, soft corals, lichens, and sea grasses, have been recently evaluated as potential drug sources. This review provides an overview of the role of PTP1B in T2DM insulin signaling and treatment, and highlights the recent findings of several compounds and extracts derived from marine organisms and their relevance as upcoming PTP1B inhibitors. In this systematic literature review, more than 60 marine-derived metabolites exhibiting PTP1B inhibitory activity are listed. Their chemical classes, structural features, relative PTP1B inhibitory potency (assessed by IC50 values), and structure⁻activity relationships (SARs) that could be drawn from the available data are discussed. The upcoming challenge in the field of marine research-metabolomics-is also addressed.
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Affiliation(s)
- Shahira M Ezzat
- Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr El-Ainy Street, Cairo 11562, Egypt.
- Department of Pharmacognosy, Faculty of Pharmacy, October University for Modern Science and Arts (MSA), Cairo 12566, Egypt.
| | - Mahitab H El Bishbishy
- Department of Pharmacognosy, Faculty of Pharmacy, October University for Modern Science and Arts (MSA), Cairo 12566, Egypt.
| | - Solomon Habtemariam
- Herbal Analysis Services UK & Pharmacognosy Research Laboratories, University of Greenwich, Central Avenue, Chatham-Maritime, Kent ME4 4TB, UK.
| | - Bahare Salehi
- Student Research Committee, Bam University of Medical Sciences, Bam 44340847, Iran.
| | - Mehdi Sharifi-Rad
- Department of Medical Parasitology, Zabol University of Medical Sciences, Zabol 61663-335, Iran.
| | - Natália Martins
- Institute for Research and Innovation in Health (i3S), University of Porto, 4200-135 Porto, Portugal.
- Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
| | - Javad Sharifi-Rad
- Zabol Medicinal Plants Research Center, Zabol University of Medical Sciences, Zabol 61615-585, Iran.
- Department of Chemistry, Richardson College for the Environmental Science Complex, The University of Winnipeg, 599 Portage Avenue, Winnipeg, MB R3B 2G3, Canada.
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21
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Yagi M, Nakatsuji Y, Maeda A, Ota H, Kamikubo R, Miyoshi N, Nakamura Y, Akagawa M. Phenethyl isothiocyanate activates leptin signaling and decreases food intake. PLoS One 2018; 13:e0206748. [PMID: 30383868 PMCID: PMC6211728 DOI: 10.1371/journal.pone.0206748] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 10/18/2018] [Indexed: 12/31/2022] Open
Abstract
Obesity, a principal risk factor for the development of diabetes mellitus, heart disease, and hypertension, is a growing and serious health problem all over the world. Leptin is a weight-reducing hormone produced by adipose tissue, which decreases food intake via hypothalamic leptin receptors (Ob-Rb) and the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway. Protein tyrosine phosphatase 1B (PTP1B) negatively regulates leptin signaling by dephosphorylating JAK2, and the increased activity of PTP1B is implicated in the pathogenesis of obesity. Hence, inhibition of PTP1B may help prevent and reduce obesity. In this study, we revealed that phenethyl isothiocyanate (PEITC), a naturally occurring isothiocyanate in certain cruciferous vegetables, potently inhibits recombinant PTP1B by binding to the reactive cysteinyl thiol. Moreover, we found that PEITC causes the ligand-independent phosphorylation of Ob-Rb, JAK2, and STAT3 by inhibiting cellular PTP1B in differentiated human SH-SY5Y neuronal cells. PEITC treatment also induced nuclear accumulation of phosphorylated STAT3, resulting in enhanced anorexigenic POMC expression and suppressed orexigenic NPY/AGRP expression. We demonstrated that oral administration of PEITC to mice significantly reduces food intake, and stimulates hypothalamic leptin signaling. Our results suggest that PEITC might help prevent and improve obesity.
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Affiliation(s)
- Miho Yagi
- Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Yukiko Nakatsuji
- Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Ayumi Maeda
- Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Hiroki Ota
- Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Ryosuke Kamikubo
- Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Noriyuki Miyoshi
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan
| | - Yoshimasa Nakamura
- Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Mitsugu Akagawa
- Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
- * E-mail:
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22
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Kim M, Baek M, Kim DJ. Protein Tyrosine Signaling and its Potential Therapeutic Implications in Carcinogenesis. Curr Pharm Des 2018. [PMID: 28625132 DOI: 10.2174/1381612823666170616082125] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Protein tyrosine phosphorylation is a crucial signaling mechanism that plays a role in epithelial carcinogenesis. Protein tyrosine kinases (PTKs) control various cellular processes including growth, differentiation, metabolism, and motility by activating major signaling pathways including STAT3, AKT, and MAPK. Genetic mutation of PTKs and/or prolonged activation of PTKs and their downstream pathways can lead to the development of epithelial cancer. Therefore, PTKs became an attractive target for cancer prevention. PTK inhibitors are continuously being developed, and they are currently used for the treatment of cancers that show a high expression of PTKs. Protein tyrosine phosphatases (PTPs), the homeostatic counterpart of PTKs, negatively regulate the rate and duration of phosphotyrosine signaling. PTPs initially were considered to be only housekeeping enzymes with low specificity. However, recent studies have demonstrated that PTPs can function as either tumor suppressors or tumor promoters, depending on their target substrates. Together, both PTK and PTP signal transduction pathways are potential therapeutic targets for cancer prevention and treatment.
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Affiliation(s)
- Mihwa Kim
- Department of Biomedical Sciences, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Minwoo Baek
- Department of Biomedical Sciences, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Dae Joon Kim
- Department of Biomedical Sciences, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
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23
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Shinde RN, Kumar GS, Eqbal S, Sobhia ME. Screening and identification of potential PTP1B allosteric inhibitors using in silico and in vitro approaches. PLoS One 2018; 13:e0199020. [PMID: 29912965 PMCID: PMC6005499 DOI: 10.1371/journal.pone.0199020] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 04/12/2018] [Indexed: 12/25/2022] Open
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a validated therapeutic target for Type 2 diabetes due to its specific role as a negative regulator of insulin signaling pathways. Discovery of active site directed PTP1B inhibitors is very challenging due to highly conserved nature of the active site and multiple charge requirements of the ligands, which makes them non-selective and non-permeable. Identification of the PTP1B allosteric site has opened up new avenues for discovering potent and selective ligands for therapeutic intervention. Interactions made by potent allosteric inhibitor in the presence of PTP1B were studied using Molecular Dynamics (MD). Computationally optimized models were used to build separate pharmacophore models of PTP1B and TCPTP, respectively. Based on the nature of interactions the target residues offered, a receptor based pharmacophore was developed. The pharmacophore considering conformational flexibility of the residues was used for the development of pharmacophore hypothesis to identify potentially active inhibitors by screening large compound databases. Two pharmacophore were successively used in the virtual screening protocol to identify potential selective and permeable inhibitors of PTP1B. Allosteric inhibition mechanism of these molecules was established using molecular docking and MD methods. The geometrical criteria values confirmed their ability to stabilize PTP1B in an open conformation. 23 molecules that were identified as potential inhibitors were screened for PTP1B inhibitory activity. After screening, 10 molecules which have good permeability values were identified as potential inhibitors of PTP1B. This study confirms that selective and permeable inhibitors can be identified by targeting allosteric site of PTP1B.
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Affiliation(s)
- Ranajit Nivrutti Shinde
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, Punjab, India
| | - G. Siva Kumar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, Punjab, India
| | - Shahbaz Eqbal
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, Punjab, India
| | - M. Elizabeth Sobhia
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, Punjab, India
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24
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Kumar AP, Nguyen MN, Verma C, Lukman S. Structural analysis of protein tyrosine phosphatase 1B reveals potentially druggable allosteric binding sites. Proteins 2018; 86:301-321. [PMID: 29235148 DOI: 10.1002/prot.25440] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/16/2017] [Accepted: 12/10/2017] [Indexed: 12/11/2022]
Abstract
Catalytic proteins such as human protein tyrosine phosphatase 1B (PTP1B), with conserved and highly polar active sites, warrant the discovery of druggable nonactive sites, such as allosteric sites, and potentially, therapeutic small molecules that can bind to these sites. Catalyzing the dephosphorylation of numerous substrates, PTP1B is physiologically important in intracellular signal transduction pathways in diverse cell types and tissues. Aberrant PTP1B is associated with obesity, diabetes, cancers, and neurodegenerative disorders. Utilizing clustering methods (based on root mean square deviation, principal component analysis, nonnegative matrix factorization, and independent component analysis), we have examined multiple PTP1B structures. Using the resulting representative structures in different conformational states, we determined consensus clustroids and used them to identify both known and novel binding sites, some of which are potentially allosteric. We report several lead compounds that could potentially bind to the novel PTP1B binding sites and can be further optimized. Considering the possibility for drug repurposing, we discovered homologous binding sites in other proteins, with ligands that could potentially bind to the novel PTP1B binding sites.
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Affiliation(s)
- Ammu Prasanna Kumar
- Department of Chemistry, College of Arts and Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Minh N Nguyen
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore
| | - Chandra Verma
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore
| | - Suryani Lukman
- Department of Chemistry, College of Arts and Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
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25
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Kim M, Morales LD, Baek M, Slaga TJ, DiGiovanni J, Kim DJ. UVB-induced nuclear translocation of TC-PTP by AKT/14-3-3σ axis inhibits keratinocyte survival and proliferation. Oncotarget 2017; 8:90674-90692. [PMID: 29207596 PMCID: PMC5710877 DOI: 10.18632/oncotarget.21794] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 09/15/2017] [Indexed: 12/28/2022] Open
Abstract
Understanding protein subcellular localization is important to determining the functional role of specific proteins. T-cell protein tyrosine phosphatase (TC-PTP) contains bipartite nuclear localization signals (NLSI and NLSII) in its C-terminus. We previously have demonstrated that the nuclear form of TC-PTP (TC45) is mainly localized to the cytoplasm in keratinocytes and it is translocated to the nucleus following UVB irradiation. Here, we report that TC45 is translocated by an AKT/14-3-3σ-mediated mechanism in response to UVB exposure, resulting in increased apoptosis and decreased keratinocyte proliferation. We demonstrate that UVB irradiation increased phosphorylation of AKT and induced nuclear translocation of 14-3-3σ and TC45. However, inhibition of AKT blocked nuclear translocation of TC45 and 14-3-3σ. Site-directed mutagenesis of 14-3-3σ binding sites within TC45 showed that a substitution at Threonine 179 (TC45/T179A) effectively blocked UVB-induced nuclear translocation of ectopic TC45 due to the disruption of the direct binding between TC45 and 14-3-3σ. Overexpression of TC45/T179A in keratinocytes resulted in a decrease of UVB-induced apoptosis which corresponded to an increase in nuclear phosphorylated STAT3, and cell proliferation was higher in TC45/T179A-overexpressing keratinocytes compared to control keratinocytes following UVB irradiation. Furthermore, deletion of TC45 NLSII blocked its UVB-induced nuclear translocation, indicating that both T179 and NLSII are required. Taken together, our findings suggest that AKT and 14-3-3σ cooperatively regulate TC45 nuclear translocation in a critical step of an early protective mechanism against UVB exposure that signals the deactivation of STAT3 in order to promote keratinocyte cell death and inhibit keratinocyte proliferation.
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Affiliation(s)
- Mihwa Kim
- Department of Biomedical Sciences, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Liza D Morales
- Department of Biomedical Sciences, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA.,South Texas Diabetes and Obesity Institute, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Minwoo Baek
- Department of Biomedical Sciences, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Thomas J Slaga
- Department of Pharmacology, School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - John DiGiovanni
- Division of Pharmacology & Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA
| | - Dae Joon Kim
- Department of Biomedical Sciences, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
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26
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Elson A. Stepping out of the shadows: Oncogenic and tumor-promoting protein tyrosine phosphatases. Int J Biochem Cell Biol 2017; 96:135-147. [PMID: 28941747 DOI: 10.1016/j.biocel.2017.09.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 09/15/2017] [Accepted: 09/16/2017] [Indexed: 12/18/2022]
Abstract
Protein tyrosine phosphorylation is critical for proper function of cells and organisms. Phosphorylation is regulated by the concerted but generically opposing activities of tyrosine kinases (PTKs) and tyrosine phosphatases (PTPs), which ensure its proper regulation, reversibility, and ability to respond to changing physiological situations. Historically, PTKs have been associated mainly with oncogenic and pro-tumorigenic activities, leading to the generalization that protein dephosphorylation is anti-oncogenic and hence that PTPs are tumor-suppressors. In many cases PTPs do suppress tumorigenesis. However, a growing body of evidence indicates that PTPs act as dominant oncogenes and drive cell transformation in a number of contexts, while in others PTPs support transformation that is driven by other oncogenes. This review summarizes the known transforming and tumor-promoting activities of the classical, tyrosine specific PTPs and highlights their potential as drug targets for cancer therapy.
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Affiliation(s)
- Ari Elson
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, 76100, Israel.
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27
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Differential oxidation of protein-tyrosine phosphatases during zebrafish caudal fin regeneration. Sci Rep 2017; 7:8460. [PMID: 28814789 PMCID: PMC5559610 DOI: 10.1038/s41598-017-07109-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 06/22/2017] [Indexed: 11/17/2022] Open
Abstract
Zebrafish have the capacity to regenerate lost tissues and organs. Amputation of the caudal fin results in a rapid, transient increase in H2O2 levels emanating from the wound margin, which is essential for regeneration, because quenching of reactive oxygen species blocks regeneration. Protein-tyrosine phosphatases (PTPs) have a central role in cell signalling and are susceptible to oxidation, which results in transient inactivation of their catalytic activity. We hypothesized that PTPs may become oxidized in response to amputation of the caudal fin. Using the oxidized PTP-specific (ox-PTP) antibody and liquid chromatography-mass spectrometry, we identified 33 PTPs in adult zebrafish fin clips of the total of 44 PTPs that can theoretically be detected based on sequence conservation. Of these 33 PTPs, 8 were significantly more oxidized 40 min after caudal fin amputation. Surprisingly, Shp2, one of the PTPs that were oxidized in response to caudal fin amputation, was required for caudal fin regeneration. In contrast, Rptpα, which was not oxidized upon amputation, was dispensable for caudal fin regeneration. Our results demonstrate that PTPs are differentially oxidized in response to caudal fin amputation and that there is a differential requirement for PTPs in regeneration.
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28
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Gulipalli KC, Bodige S, Ravula P, Endoori S, Vanaja GR, Suresh Babu G, Narendra Sharath Chandra JN, Seelam N. Design, synthesis, in silico and in vitro evaluation of thiophene derivatives: A potent tyrosine phosphatase 1B inhibitor and anticancer activity. Bioorg Med Chem Lett 2017; 27:3558-3564. [PMID: 28579122 DOI: 10.1016/j.bmcl.2017.05.047] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/06/2017] [Accepted: 05/16/2017] [Indexed: 11/24/2022]
Abstract
A series of novel methyl 4-(4-amidoaryl)-3-methoxythiophene-2-carboxylate derivatives were designed against the active site of protein tyrosine phosphatise 1B (PTP1B) enzyme using MOE.2008.10. These molecules are also subjected for in silico toxicity prediction studies and considering their corresponding drug scores, it implied that, the molecules are promising as anticancer agents. The designed compounds were synthesized by using suitable methods and characterized. They were subjected to inhibitory activity against PTP1B and in vitro anticancer activity by MTT assay. Most of the tested compounds showed potent inhibitory activity against PTP1B, among the compounds tested, compound 5b exhibited the highest activity (IC50=5.25µM) and remarkable cytotoxic activity at 0.09µM of IC50 against the MCF-7 cell line. In addition to this, compound 5c also showed potential anticancer activity at 2.22µM of IC50 against MCF-7 and 0.72µM against HepG2 cell lines as well as PTP1B inhibitory activity at IC50 of 6.37µM.
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Affiliation(s)
- Kali Charan Gulipalli
- Department of Chemistry, K L University, Green Fields, Vaddeswaram, Guntur 522502, India
| | - Srinu Bodige
- Department of Chemistry, K L University, Green Fields, Vaddeswaram, Guntur 522502, India
| | - Parameshwar Ravula
- Department of Pharmaceutical Chemistry, Gurunanak Institutions Technical Campus, School of Pharmacy, Hyderabad, India
| | - Srinivas Endoori
- Department of Chemistry, K L University, Green Fields, Vaddeswaram, Guntur 522502, India
| | - G R Vanaja
- Department of Animal Biology, University of Hyderabad, Hyderabad 500046, India
| | - G Suresh Babu
- Department of Animal Biology, University of Hyderabad, Hyderabad 500046, India
| | | | - Nareshvarma Seelam
- Department of Chemistry, K L University, Green Fields, Vaddeswaram, Guntur 522502, India.
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29
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Targeted disruption of TC-PTP in the proliferative compartment augments STAT3 and AKT signaling and skin tumor development. Sci Rep 2017; 7:45077. [PMID: 28322331 PMCID: PMC5359614 DOI: 10.1038/srep45077] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 02/17/2017] [Indexed: 12/30/2022] Open
Abstract
Tyrosine phosphorylation is a vital mechanism that contributes to skin carcinogenesis. It is regulated by the counter-activities of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Here, we report the critical role of T-cell protein tyrosine phosphatase (TC-PTP), encoded by Ptpn2, in chemically-induced skin carcinogenesis via the negative regulation of STAT3 and AKT signaling. Using epidermal specific TC-PTP knockout (K14Cre.Ptpn2fl/fl) mice, we demonstrate loss of TC-PTP led to a desensitization to tumor initiator 7,12-dimethylbenz[a]anthracene (DMBA)-induced apoptosis both in vivo epidermis and in vitro keratinocytes. TC-PTP deficiency also resulted in a significant increase in epidermal thickness and hyperproliferation following exposure to the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). Western blot analysis showed that both phosphorylated STAT3 and phosphorylated AKT expressions were significantly increased in epidermis of TC-PTP-deficient mice compared to control mice following TPA treatment. Inhibition of STAT3 or AKT reversed the effects of TC-PTP deficiency on apoptosis and proliferation. Finally, TC-PTP knockout mice showed a shortened latency of tumorigenesis and significantly increased numbers of tumors during two-stage skin carcinogenesis. Our findings reveal that TC-PTP has potential as a novel target for the prevention of skin cancer through its role in the regulation of STAT3 and AKT signaling.
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30
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Jais A, Brüning JC. Hypothalamic inflammation in obesity and metabolic disease. J Clin Invest 2017; 127:24-32. [PMID: 28045396 DOI: 10.1172/jci88878] [Citation(s) in RCA: 284] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Over the last years, hypothalamic inflammation has been linked to the development and progression of obesity and its sequelae. There is accumulating evidence that this inflammation not only impairs energy balance but also contributes to obesity-associated insulin resistance. Elevated activation of key inflammatory mediators such as JNK and IκB kinase (IKK) occurs rapidly upon consumption of a high-fat diet, even prior to significant weight gain. This activation of hypothalamic inflammatory pathways results in the uncoupling of caloric intake and energy expenditure, fostering overeating and further weight gain. In addition, these inflammatory processes contribute to obesity-associated insulin resistance and deterioration of glucose metabolism via altered neurocircuit functions. An understanding of the contributions of different neuronal and non-neuronal cell types to hypothalamic inflammatory processes, and delineation of the differences and similarities between acute and chronic activation of these inflammatory pathways, will be critical for the development of novel therapeutic strategies for the treatment of obesity and metabolic syndrome.
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31
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Song GJ, Jung M, Kim JH, Park H, Rahman MH, Zhang S, Zhang ZY, Park DH, Kook H, Lee IK, Suk K. A novel role for protein tyrosine phosphatase 1B as a positive regulator of neuroinflammation. J Neuroinflammation 2016; 13:86. [PMID: 27095436 PMCID: PMC4837589 DOI: 10.1186/s12974-016-0545-3] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 04/11/2016] [Indexed: 01/28/2023] Open
Abstract
Background Protein tyrosine phosphatase 1B (PTP1B) is a member of the non-transmembrane phosphotyrosine phosphatase family. Recently, PTP1B has been proposed to be a novel target of anti-cancer and anti-diabetic drugs. However, the role of PTP1B in the central nervous system is not clearly understood. Therefore, in this study, we sought to define PTP1B’s role in brain inflammation. Methods PTP1B messenger RNA (mRNA) and protein expression levels were examined in mouse brain and microglial cells after LPS treatment using RT-PCR and western blotting. Pharmacological inhibitors of PTP1B, NF-κB, and Src kinase were used to analyze these signal transduction pathways in microglia. A Griess reaction protocol was used to determine nitric oxide (NO) concentrations in primary microglia cultures and microglial cell lines. Proinflammatory cytokine production was measured by RT-PCR. Western blotting was used to assess Src phosphorylation levels. Immunostaining for Iba-1 was used to determine microglial activation in the mouse brain. Results PTP1B expression levels were significantly increased in the brain 24 h after LPS injection, suggesting a functional role for PTP1B in brain inflammation. Microglial cells overexpressing PTP1B exhibited an enhanced production of NO and gene expression levels of TNF-α, iNOS, and IL-6 following LPS exposure, suggesting that PTP1B potentiates the microglial proinflammatory response. To confirm the role of PTP1B in neuroinflammation, we employed a highly potent and selective inhibitor of PTP1B (PTP1Bi). In LPS- or TNF-α-stimulated microglial cells, in vitro blockade of PTP1B activity using PTP1Bi markedly attenuated NO production. PTP1Bi also suppressed the expression levels of iNOS, COX-2, TNF-α, and IL-1β. PTP1B activated Src by dephosphorylating the Src protein at a negative regulatory site. PTP1B-mediated Src activation led to an enhanced proinflammatory response in the microglial cells. An intracerebroventricular injection of PTP1Bi significantly attenuated microglial activation in the hippocampus and cortex of LPS-injected mice compared to vehicle-injected mice. The gene expression levels of proinflammatory cytokines were also significantly suppressed in the brain by a PTP1Bi injection. Together, these data suggest that PTP1Bi has an anti-inflammatory effect in a mouse model of neuroinflammation. Conclusions This study demonstrates that PTP1B is an important positive regulator of neuroinflammation and is a promising therapeutic target for neuroinflammatory and neurodegenerative diseases. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0545-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Gyun Jee Song
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Myungsu Jung
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Jong-Heon Kim
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Hana Park
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Md Habibur Rahman
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Sheng Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, 47907, USA
| | - Zhong-Yin Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, 47907, USA
| | - Dong Ho Park
- Department of Ophthalmology, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Hyun Kook
- Department of Pharmacology, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - In-Kyu Lee
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Kyoungho Suk
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea.
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32
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Loss of protein tyrosine phosphatase, non-receptor type 2 is associated with activation of AKT and tamoxifen resistance in breast cancer. Breast Cancer Res Treat 2015. [PMID: 26208487 DOI: 10.1007/s10549-015-3516-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Breast cancer is a heterogeneous disease and new clinical markers are needed to individualise disease management and therapy further. Alterations in the PI3K/AKT pathway, mainly PIK3CA mutations, have been shown frequently especially in the luminal breast cancer subtypes, suggesting a cross-talk between ER and PI3K/AKT. Aberrant PI3K/AKT signalling has been connected to poor response to anti-oestrogen therapies. In vitro studies have shown protein tyrosine phosphatase, non-receptor type 2 (PTPN2) as a previously unknown negative regulator of the PI3K/AKT pathway. Here, we evaluate possible genomic alterations in the PTPN2 gene and its potential as a new prognostic and treatment predictive marker for endocrine therapy benefit in breast cancer. PTPN2 gene copy number was assessed by real-time PCR in 215 tumour samples from a treatment randomised study consisting of postmenopausal patients diagnosed with stage II breast cancer 1976-1990. Corresponding mRNA expression levels of PTPN2 were evaluated in 86 available samples by the same methodology. Gene copy loss of PTPN2 was detected in 16% (34/215) of the tumours and this was significantly correlated with lower levels of PTPN2 mRNA. PTPN2 gene loss and lower mRNA levels were associated with activation of AKT and a poor prognosis. Furthermore, PTPN2 gene loss was a significant predictive marker of poor benefit from tamoxifen treatment. In conclusion, genomic loss of PTPN2 may be a previously unknown mechanism of PI3K/AKT upregulation in breast cancer. PTPN2 status is a potential new clinical marker of endocrine treatment benefit which could guide further individualised therapies in breast cancer.
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Design and synthesis of novel 1,2-dithiolan-4-yl benzoate derivatives as PTP1B inhibitors. Bioorg Med Chem Lett 2015; 25:2211-6. [PMID: 25872983 DOI: 10.1016/j.bmcl.2015.03.060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Revised: 03/19/2015] [Accepted: 03/20/2015] [Indexed: 11/23/2022]
Abstract
A series of novel 1,2-dithiolan-4-yl benzoate compounds were synthesized and evaluated for in vitro PTP1B inhibitory activity. Some derivatives exhibited improved PTP1B inhibitory activity and selectivity compared to hit 6a, a compound from in-house library screening inspired by marine cyclic disulfide. The preliminary SAR analysis with assistance of molecular modeling approach revealed 6j (IC50=0.59μM) as the most potent PTP1B inhibitor among all derivatives.
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34
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Genetics of serum concentration of IL-6 and TNFα in systemic lupus erythematosus and rheumatoid arthritis: a candidate gene analysis. Clin Rheumatol 2015; 34:1375-82. [PMID: 25652333 DOI: 10.1007/s10067-015-2881-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 01/05/2015] [Accepted: 01/19/2015] [Indexed: 12/19/2022]
Abstract
Elevated concentrations of inflammatory mediators are characteristic of autoimmune disease accompanied by chronic or recurrent inflammation. We examined the hypothesis that mediators of inflammation known to be elevated in systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) are associated with genetic polymorphism previously identified in studies of inflammatory disease. Serum interleukin 6 (IL-6) and tumor necrosis factor alpha (TNFα) concentrations in patients with SLE (n = 117) or RA (n = 164) and in inflammatory disease-free control subjects (n = 172) were measured by multiplex ELISA. Candidate genes were chosen from studies of autoimmune and inflammatory disease. Genotypes were determined for 345 SNP markers in 75 genes. Association between serum analytes and single alleles was tested by linear regression. Polymorphisms in several genes were associated with IL-6 levels (including IL10, TYK2, and CD40L in SLE and DRB1, NOD2, and CSF1 in RA) or with TNFα levels (including TNFSF4 and CSF2 in SLE and PTPN2, DRB1, and NOD2 in RA). Some associations were shared between disease and control groups or between IL-6 and TNFα within a group. In conclusion, variation in genes implicated in disease pathology is associated with serum IL-6 or TNFα concentration. Some genetic associations are more apparent in healthy controls than in SLE or RA, suggesting dysregulation of the principal mediators of chronic inflammation in disease. Susceptibility genes may affect inflammatory response with variable effect on disease etiology.
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Lee H, Morales LD, Slaga TJ, Kim DJ. Activation of T-cell protein-tyrosine phosphatase suppresses keratinocyte survival and proliferation following UVB irradiation. J Biol Chem 2014; 290:13-24. [PMID: 25406309 DOI: 10.1074/jbc.m114.611681] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chronic exposure to UV radiation can contribute to the development of skin cancer by promoting protein-tyrosine kinase (PTK) signaling. Studies show that exposure to UV radiation increases the ligand-independent activation of PTKs and induces protein-tyrosine phosphatase (PTP) inactivation. In the present work, we report that T-cell PTP (TC-PTP) activity is stimulated during the initial response to UVB irradiation, which leads to suppression of keratinocyte cell survival and proliferation via the down-regulation of STAT3 signaling. Our results show that TC-PTP-deficient keratinocyte cell lines expressed a significantly increased level of phosphorylated STAT3 after exposure to low dose UVB. This increase corresponded with increased cell proliferation in TC-PTP-deficient keratinocytes following UVB irradiation. Loss of TC-PTP also reduced UVB-induced apoptosis. Corroborating with these results, overexpression of TC-PTP in keratinocyte cell lines yielded a decrease in phosphorylated STAT3 levels, which corresponded with a significant decrease in cell proliferation in response to low dose UVB. We demonstrate that TC-PTP activity was increased upon UVB exposure, and overexpression of TC-PTP in keratinocyte cell lines further increased its activity in the presence of UVB. Treatment of TC-PTP-deficient keratinocytes with the STAT3 inhibitor STA21 significantly reduced cell viability following UVB exposure in comparison with untreated TC-PTP-deficient keratinocytes, confirming that the effect of TC-PTP on cell viability is mediated by STAT3 dephosphorylation. Combined, our results indicate that UVB-mediated activation of TC-PTP plays an important role in the STAT3-dependent regulation of keratinocyte cell proliferation and survival. Furthermore, these results suggest that TC-PTP may be a novel potential target for the prevention of UVB-induced skin cancer.
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Affiliation(s)
- Hyunseung Lee
- From the Edinburg Regional Academic Health Center, Medical Research Division, University of Texas Health Science Center at San Antonio, Edinburg, Texas 78541 and the Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Liza D Morales
- From the Edinburg Regional Academic Health Center, Medical Research Division, University of Texas Health Science Center at San Antonio, Edinburg, Texas 78541 and
| | - Thomas J Slaga
- the Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Dae Joon Kim
- From the Edinburg Regional Academic Health Center, Medical Research Division, University of Texas Health Science Center at San Antonio, Edinburg, Texas 78541 and the Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
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Qin H, Zhang X, Ye F, Zhong L. High-fat diet-induced changes in liver thioredoxin and thioredoxin reductase as a novel feature of insulin resistance. FEBS Open Bio 2014; 4:928-35. [PMID: 25426412 PMCID: PMC4239481 DOI: 10.1016/j.fob.2014.10.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 10/28/2014] [Accepted: 10/28/2014] [Indexed: 12/25/2022] Open
Abstract
High-fat diet (HFD) can induce oxidative stress. Thioredoxin (Trx) and thioredoxin reductase (TrxR) are critical antioxidant proteins but how they are affected by HFD remains unclear. Using HFD-induced insulin-resistant mouse model, we show here that liver Trx and TrxR are significantly decreased, but, remarkably, the degree of their S-acylation is increased after consuming HFD. These HFD-induced changes in Trx/TrxR may reflect abnormalities of lipid metabolism and insulin signaling transduction. HFD-driven accumulation of 4-hydroxynonenal is another potential mechanism behind inactivation and decreased expression of Trx/TrxR. Thus, we propose HFD-induced impairment of liver Trx/TrxR as major contributor to oxidative stress and as a novel feature of insulin resistance.
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Key Words
- 4-HNE, 4-hydroxynonenal
- ASK-1, apoptosis signal-regulating kinase-1
- Gpx, glutathione peroxidase
- HFD, high-fat diet
- High-fat diet
- IRS-1, insulin receptor substrate-1
- ITT, insulin tolerance test
- Insulin resistance
- OGTT, oral glucose tolerance test
- PTP-1B, protein-tyrosine phophatase-1B
- S-acylation
- Thioredoxin
- Thioredoxin reductase
- Trx, thioredoxin
- TrxR, thioredoxin reductase
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Affiliation(s)
- Huijun Qin
- College of Life Sciences, University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Xiaolin Zhang
- Institute of Materia Medica, Chinese Academy of Medical Sciences & Perking Union Medical College, 100050 Beijing, China
| | - Fei Ye
- Institute of Materia Medica, Chinese Academy of Medical Sciences & Perking Union Medical College, 100050 Beijing, China
| | - Liangwei Zhong
- College of Life Sciences, University of Chinese Academy of Sciences, 100049 Beijing, China
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Maeda A, Kai K, Ishii M, Ishii T, Akagawa M. Safranal, a novel protein tyrosine phosphatase 1B inhibitor, activates insulin signaling in C2C12 myotubes and improves glucose tolerance in diabetic KK-Aymice. Mol Nutr Food Res 2014; 58:1177-89. [DOI: 10.1002/mnfr.201300675] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 12/24/2013] [Accepted: 01/02/2014] [Indexed: 02/05/2023]
Affiliation(s)
- Ayumi Maeda
- Department of Biological Chemistry; Division of Applied Life Science; Graduate School of Life and Environmental Sciences; Osaka Prefecture University; Sakai Japan
| | - Kenji Kai
- Department of Biological Chemistry; Division of Applied Life Science; Graduate School of Life and Environmental Sciences; Osaka Prefecture University; Sakai Japan
| | - Megumi Ishii
- Department of Biological Chemistry; Division of Applied Life Science; Graduate School of Life and Environmental Sciences; Osaka Prefecture University; Sakai Japan
| | - Takeshi Ishii
- Department of Food and Nutritional Sciences, and Global COE Program; University of Shizuoka; Shizuoka Japan
| | - Mitsugu Akagawa
- Department of Biological Chemistry; Division of Applied Life Science; Graduate School of Life and Environmental Sciences; Osaka Prefecture University; Sakai Japan
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Shi L, Zhang Q, Xu B, Jiang X, Dai Y, Zhang CY, Zen K. Sustained high protein-tyrosine phosphatase 1B activity in the sperm of obese males impairs the sperm acrosome reaction. J Biol Chem 2014; 289:8432-41. [PMID: 24519936 DOI: 10.1074/jbc.m113.517466] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Evidence of a causal link between male obesity and subfertility or infertility has been demonstrated previously. However, the mechanism underlying this link is incompletely understood. Here, we report that sustained high protein-tyrosine phosphatase 1B (PTP1B) activity in sperm of obese donors plays an essential role in coupling male obesity and subfertility or infertility. First, PTP1B level and activity were significantly higher in sperm from ob/ob mice than in wild-type littermates. High PTP1B level and activity in sperm was also observed in obese patients compared with non-obese donors. The enhanced sperm PTP1B level and activity in ob/ob mice and obese patients correlated with a defect of the sperm acrosome reaction (AR). Second, treating sperm from male ob/ob mice or obese men with a specific PTP1B inhibitor largely restored the sperm AR. Finally, blockade of sperm AR by enhanced PTP1B activity in male ob/ob mice or obese men was due to prolonged dephosphorylation of N-ethylmaleimide-sensitive factor by PTP1B, leading to the inability to reassemble the trans-SNARE complexes, which is a critical step in sperm acrosomal exocytosis. In summary, our study demonstrates for the first time that a sustained high PTP1B level or activity in the sperm of obese donors causes a defect of sperm AR and that PTP1B is a novel potential therapeutic target for male infertility treatment.
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Affiliation(s)
- Lei Shi
- From the Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210093, China and
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Guerra B, Ponce-González JG, Morales-Alamo D, Guadalupe-Grau A, Kiilerich K, Fuentes T, Ringholm S, Biensø RS, Santana A, Lundby C, Pilegaard H, Calbet JAL. Leptin signaling in skeletal muscle after bed rest in healthy humans. Eur J Appl Physiol 2013; 114:345-57. [PMID: 24292882 DOI: 10.1007/s00421-013-2779-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 11/18/2013] [Indexed: 12/22/2022]
Abstract
PURPOSE This study aimed at determining the effects of bed rest on the skeletal muscle leptin signaling system. METHODS Deltoid and vastus lateralis muscle biopsies and blood samples were obtained from 12 healthy young men (mean ± SD, BMI 22.8 ± 2.7 kg/m(2)) before and after 7 days of bed rest. Leptin receptor isoforms (OB-Rs), suppressor of cytokine signaling 3 (SOCS3) and protein tyrosine phosphatase 1B (PTP1B) protein expression and signal transducer and activator of transcription 3 (STAT3) phosphorylation were analyzed by Western blot. RESULTS After bed rest basal insulin concentration was increased by 53% (P < 0.05), the homeostasis model assessment (HOMA) by 40% (P < 0.05), and serum leptin concentration by 35% (P < 0.05) with no changes in body fat mass. Although the soluble isoform of the leptin receptor (s-OBR) remained unchanged, the molar excess of leptin over sOB-R was increased by 1.4-fold after bed rest (P < 0.05). OB-Rs and SOCS3 protein expression, and STAT3 phosphorylation level remained unaffected in deltoid and vastus lateralis by bed rest, as PTP1B in the deltoid. PTP1B was increased by 90% with bed rest in the vastus lateralis (P < 0.05). There was a linear relationship between the increase in vastus lateralis PTP1B and the increase in both basal insulin concentrations (r = 0.66, P < 0.05) and HOMA (r = 0.68, P < 0.05) with bed rest. CONCLUSIONS One week of bed rest is associated with increased leptin levels without augmenting STAT3 phosphorylation indicating some degree of leptin resistance in skeletal muscle, which can be explained, at least in part, by an elevation of PTP1B protein content in the vastus lateralis muscle.
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Affiliation(s)
- Borja Guerra
- Departamento de Educación Física, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira, 35017, Las Palmas de Gran Canaria, Canary Island, Spain,
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41
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Ayoub E, Hall A, Scott AM, Chagnon MJ, Miquel G, Hallé M, Noda M, Bikfalvi A, Tremblay ML. Regulation of the Src kinase-associated phosphoprotein 55 homologue by the protein tyrosine phosphatase PTP-PEST in the control of cell motility. J Biol Chem 2013; 288:25739-25748. [PMID: 23897807 DOI: 10.1074/jbc.m113.501007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PTP-PEST is a cytosolic ubiquitous protein tyrosine phosphatase (PTP) that contains, in addition to its catalytic domain, several protein-protein interaction domains that allow it to interface with several signaling pathways. Among others, PTP-PEST is a key regulator of cellular motility and cytoskeleton dynamics. The complexity of the PTP-PEST interactome underscores the necessity to identify its interacting partners and physiological substrates in order to further understand its role in focal adhesion complex turnover and actin organization. Using a modified yeast substrate trapping two-hybrid system, we identified a cytosolic adaptor protein named Src kinase-associated phosphoprotein 55 homologue (SKAP-Hom) as a novel substrate of PTP-PEST. To confirm PTP-PEST interaction with SKAP-Hom, in vitro pull down assays were performed demonstrating that the PTP catalytic domain and Proline-rich 1 (P1) domain are respectively binding to the SKAP-Hom Y260 and Y297 residues and its SH3 domain. Subsequently, we generated and rescued SKAP-Hom-deficient mouse embryonic fibroblasts (MEFs) with WT SKAP-Hom, SKAP-Hom tyrosine mutants (Y260F, Y260F/Y297F), or SKAP-Hom SH3 domain mutant (W335K). Given the role of PTP-PEST, wound-healing and trans-well migration assays were performed using the generated lines. Indeed, SKAP-Hom-deficient MEFs showed a defect in migration compared with WT-rescued MEFs. Interestingly, the SH3 domain mutant-rescued MEFs showed an enhanced cell migration corresponding potentially with higher tyrosine phosphorylation levels of SKAP-Hom. These findings suggest a novel role of SKAP-Hom and its phosphorylation in the regulation of cellular motility. Moreover, these results open new avenues by which PTP-PEST regulates cellular migration, a hallmark of metastasis.
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Affiliation(s)
- Emily Ayoub
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Anita Hall
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Adam M Scott
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Mélanie J Chagnon
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Géraldine Miquel
- INSERM U1029 and; Université Bordeaux, Avenue des Facultés, 33 405 Talence, France
| | - Maxime Hallé
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Masaharu Noda
- the Division of Molecular Neurobiology, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan, and
| | - Andreas Bikfalvi
- INSERM U1029 and; Université Bordeaux, Avenue des Facultés, 33 405 Talence, France
| | - Michel L Tremblay
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada,.
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Nunes-Xavier CE, Martín-Pérez J, Elson A, Pulido R. Protein tyrosine phosphatases as novel targets in breast cancer therapy. Biochim Biophys Acta Rev Cancer 2013; 1836:211-26. [PMID: 23756181 DOI: 10.1016/j.bbcan.2013.06.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Accepted: 06/01/2013] [Indexed: 02/07/2023]
Abstract
Breast cancer is linked to hyperactivation of protein tyrosine kinases (PTKs), and recent studies have unveiled that selective tyrosine dephosphorylation by protein tyrosine phosphatases (PTPs) of specific substrates, including PTKs, may activate or inactivate oncogenic pathways in human breast cancer cell growth-related processes. Here, we review the current knowledge on the involvement of PTPs in breast cancer, as major regulators of breast cancer therapy-targeted PTKs, such as HER1/EGFR, HER2/Neu, and Src. The functional interplay between PTKs and PTK-activating or -inactivating PTPs, and its implications in novel breast cancer therapies based on targeting of specific PTPs, are discussed.
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Affiliation(s)
- Caroline E Nunes-Xavier
- BioCruces Health Research Institute, Hospital de Cruces, Plaza Cruces s/n, 48903 Barakaldo, Spain
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Song DD, Chen Y, Li ZY, Guan YF, Zou DJ, Miao CY. Protein tyrosine phosphatase 1B inhibits adipocyte differentiation and mediates TNFα action in obesity. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1368-76. [PMID: 23711960 DOI: 10.1016/j.bbalip.2013.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Revised: 04/29/2013] [Accepted: 05/16/2013] [Indexed: 01/06/2023]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a negative regulator of systemic glucose and insulin homeostasis; however, its exact role in adipocytes is poorly understood. This study was to elucidate the role of PTP1B in adipocyte differentiation and its implication in obesity. During differentiation of 3T3-L1 white preadipocytes, PTP1B decreased progressively with adipocyte maturation. Lentivirus-mediated PTP1B overexpression in preadipocytes delayed adipocyte differentiation, shown as lack of mature adipocytes, low level of lipid accumulation, and down-regulation of main markers (PPARγ2, SREBP-1c, FAS and LPL). In contrast, lentivirus-mediated PTP1B knockdown accelerated adipocyte differentiation, demonstrated as full of mature adipocytes, high level of lipid accumulation, and up-regulation of main markers. Dominant-negative inhibition on endogenous PTP1B by lentivirus-mediated overexpression of PTP1B double mutant in Tyr-46 and Asp-181 residues (LV-D/A-Y/F) also stimulated adipogenesis, more efficient than PTP1B knockdown. Diet-induced obesity mice exhibited an up-regulation of PTP1B and TNFα accompanied by a down-regulation of PPARγ2 in white adipose tissue. TNFα recombinant protein impeded PTP1B reduction and inhibited adipocyte differentiation in vitro; this inhibitory effect was prevented by LV-D/A-Y/F. Moreover, PTP1B inhibitor treatment improved adipogenesis and suppressed TNFα in adipose tissue of obese mice. All together, PTP1B negatively regulates adipocyte development and may mediate TNFα action to impair adipocyte differentiation in obesity. Our study provides novel evidence for the importance of PTP1B in obesity and for the potential application of PTP1B inhibitors.
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Affiliation(s)
- Dan-Dan Song
- Department of Endocrinology, Second Military Medical University, Shanghai, China
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Tecilazich F, Dinh TL, Veves A. Emerging drugs for the treatment of diabetic ulcers. Expert Opin Emerg Drugs 2013; 18:207-17. [PMID: 23687931 DOI: 10.1517/14728214.2013.802305] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Diabetic ulcers are chronic nonhealing ulcerations that despite the available medical tools still result in high amputation rates. Growing evidence suggests that alteration of the biochemical milieu of the chronic wound plays a significant role in impaired diabetic wound healing. AREAS COVERED The basic pathophysiology and the conventional treatment strategy of diabetic foot ulcers have been reviewed in the first section. In the second part, the most up-to-date bench and translational research in the field are described. The third section focuses on the drugs currently under development and the ongoing clinical trials evaluating their safety and efficacy. Finally, the major drug development issues and the possible scientific approaches to overcome them are analyzed. EXPERT OPINION Significant strides in understanding the chronic wound development have led to the development of topical therapies to address aberrant expression of growth factors and overexpression of inflammatory cytokines. Current research in the laboratory suggests that while decreased growth factor expression occurs at the local wound level, increased systemic serum levels of growth factors suggest growth factor resistance.
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Affiliation(s)
- Francesco Tecilazich
- Harvard Medical School, Joslin-Beth Israel Deaconess Foot Center, and Microcirculation Lab, Beth Israel Deaconess Foot Center, Boston, MA, USA
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Ren W, Sun Y, Cheema S, Du K. Interaction of constitutive photomorphogenesis 1 protein with protein-tyrosine phosphatase 1B suppresses protein-tyrosine phosphatase 1B activity and enhances insulin signaling. J Biol Chem 2013; 288:10902-13. [PMID: 23439647 PMCID: PMC3624470 DOI: 10.1074/jbc.m112.369371] [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: 02/11/2013] [Indexed: 11/06/2022] Open
Abstract
Recent studies reveal that COP1 suppresses the expression of gluconeogenetic genes and prohibits hepatic glucose production. To get more insight into COP1 in hepatic cells, we examined the impact of COP1 on insulin-responsive genes and insulin signaling. We found that COP1 increased the responsiveness of insulin-modulated genes to insulin in that it promoted the expression of insulin-induced genes and inhibited that of insulin-suppressed genes and that COP1 enhanced insulin signaling as it promoted phosphorylation of Akt and ERK as well as tyrosine phosphorylation of IRβ induced by insulin. To delineate the mechanism under which COP1 modulates insulin signaling, we examined the possibility that COP1 modulates the activity of PTP1B, the major insulin receptor tyrosine phosphatase. The results indicated that COP1 physically interacted with PTP1B and suppressed PTP1B phosphatase activity as well as the association of PTP1B with IRβ. We suggest that COP1 is a positive regulator of hepatic insulin signaling.
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Affiliation(s)
- Wenying Ren
- From the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111
| | - Yingmin Sun
- From the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111
| | - Sarwat Cheema
- From the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111
| | - Keyong Du
- From the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111
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Vogt MC, Brüning JC. CNS insulin signaling in the control of energy homeostasis and glucose metabolism - from embryo to old age. Trends Endocrinol Metab 2013; 24:76-84. [PMID: 23265947 DOI: 10.1016/j.tem.2012.11.004] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 11/07/2012] [Accepted: 11/13/2012] [Indexed: 10/27/2022]
Abstract
Central nervous system (CNS) insulin signaling regulates energy and glucose homeostasis by acting on hypothalamic neurocircuits and higher brain circuits such as the dopaminergic system. However, overnutrition, obesity, and type 2 diabetes mellitus (T2DM) induce insulin resistance selectively in different regions of the brain, thereby impairing energy homeostasis and augmenting disease progression. Moreover, fetal hyperinsulinemia in response to maternal overnutrition, obesity, and diabetes disrupts hypothalamic neurocircuit development and predisposes to metabolic disorders later in life. In light of the current obesity and diabetes epidemic, we review the molecular basis of insulin action and resistance in the CNS, mechanisms which are causal to the development of these metabolic disorders, both in the neonate and in the adult.
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Affiliation(s)
- Merly C Vogt
- Max Planck Institute for Neurological Research, D-50931 Cologne, Germany
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Muppirala M, Gupta V, Swarup G. Emerging role of tyrosine phosphatase, TCPTP, in the organelles of the early secretory pathway. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:1125-32. [PMID: 23328081 DOI: 10.1016/j.bbamcr.2013.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 01/04/2013] [Accepted: 01/08/2013] [Indexed: 01/21/2023]
Abstract
T-cell protein tyrosine phosphatase, TCPTP, is a ubiquitously expressed non-receptor type tyrosine phosphatase. There are two splice variants of TCPTP, TC48 and TC45, which differ in their sub-cellular localizations and functions. TC45 is a nuclear protein, which has both nuclear and cytoplasmic substrates, and is involved in many signaling events including endocytic recycling of platelet-derived growth factor β-receptor. TC48 is a predominantly endoplasmic reticulum (ER)-localizing protein, which dephosphorylates some of the substrates of TC45 at the ER. However, recently few specific substrates for TC48 have been identified. These include C3G (RapGEF1), syntaxin 17 and BCR-Abl. TC48 moves from the ER to post-ER compartments, the ER-Golgi intermediate compartment (ERGIC) and Golgi, and it is retrieved back to the ER. The retrieval of ER proteins from post-ER compartments is generally believed as a mechanism of targeting these proteins to the ER. However, it is possible that this shuttling of TC48 serves to regulate signaling in the early secretory pathway. For example, TC48 dephosphorylates phosphorylated C3G at the Golgi and inhibits neurite outgrowth. TC48 interacts with and dephosphorylates syntaxin 17, which is an ER and ERGIC-localizing protein involved in vesicle transport. A yeast two-hybrid screen identified several unique interacting partners of TC48 belonging to two groups - proteins involved in vesicle trafficking and proteins involved in cell adhesion. These interacting proteins could be substrates or regulators of TC48 function and localization. Thus, the role of TC48 seems to be more diverse, which is still to be explored.
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Affiliation(s)
- Madhavi Muppirala
- Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Hyderabad, India
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48
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Muppirala M, Gupta V, Swarup G. Tyrosine phosphorylation of a SNARE protein, syntaxin 17: implications for membrane trafficking in the early secretory pathway. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:2109-19. [PMID: 23006999 DOI: 10.1016/j.bbamcr.2012.09.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 09/13/2012] [Indexed: 10/27/2022]
Abstract
The T-cell protein tyrosine phosphatase is expressed as two splice variants - TC45, a nuclear protein, and TC48, which is localized predominantly in the ER (endoplasmic reticulum). Yeast two-hybrid screening revealed direct interaction of TC48 with Syntaxin17, a SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) protein localized predominantly in the ER and to some extent in the ER-Golgi intermediate compartment. Syntaxin 17 did not interact with TC45. C-terminal 40 amino acids of TC48 were sufficient for interaction with syntaxin 17. Overexpressed syntaxin 17 was phosphorylated at tyrosine upon pervanadate treatment (a tyrosine phosphatase inhibitor/tyrosine kinase activator) of COS-1 cells. Mutational analysis identified Tyr156 in the cytoplasmic domain as the major site of phosphorylation. Endogenous syntaxin 17 was phosphorylated by pervanadate treatment in CHO and MIN6 cells but was not phosphorylated in a variety of other cell lines tested. c-Abl was identified as one of the kinases, which phosphorylates syntaxin 17 in MIN6 cells. Phosphorylation of endogenous and overexpressed syntaxin 17 was reduced in the presence of IGF receptor and EGF receptor kinase inhibitors. Serum depletion reduced pervanadate-induced phosphorylation of endogenous syntaxin 17. TC48 coexpression reduced phosphorylation of syntaxin 17 by pervanadate and purified TC48 directly dephosphorylated syntaxin 17. β-COP dispersal by overexpressed syntaxin 17 was reduced after pervanadate-induced phosphorylation. A phospho-mimicking mutant (Y156E) of syntaxin 17 showed reduced interaction with COPI vesicles. These results suggest that tyrosine phosphorylation of syntaxin 17 is likely to have a role in regulating syntaxin 17 dependent membrane trafficking in the early secretory pathway.
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Affiliation(s)
- Madhavi Muppirala
- Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Uppal Road, Hyderabad 500 007, India
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Wu C, Kraft P, Zhai K, Chang J, Wang Z, Li Y, Hu Z, He Z, Jia W, Abnet CC, Liang L, Hu N, Miao X, Zhou Y, Liu Z, Zhan Q, Liu Y, Qiao Y, Zhou Y, Jin G, Guo C, Lu C, Yang H, Fu J, Yu D, Freedman ND, Ding T, Tan W, Goldstein AM, Wu T, Shen H, Ke Y, Zeng Y, Chanock SJ, Taylor PR, Lin D. Genome-wide association analyses of esophageal squamous cell carcinoma in Chinese identify multiple susceptibility loci and gene-environment interactions. Nat Genet 2012; 44:1090-7. [PMID: 22960999 DOI: 10.1038/ng.2411] [Citation(s) in RCA: 205] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 08/16/2012] [Indexed: 12/13/2022]
Abstract
We conducted a genome-wide association study (GWAS) and a genome-wide gene-environment interaction analysis of esophageal squamous-cell carcinoma (ESCC) in 2,031 affected individuals (cases) and 2,044 controls with independent validation in 8,092 cases and 8,620 controls. We identified nine new ESCC susceptibility loci, of which seven, at chromosomes 4q23, 16q12.1, 17q21, 22q12, 3q27, 17p13 and 18p11, had a significant marginal effect (P=1.78×10(-39) to P=2.49×10(-11)) and two of which, at 2q22 and 13q33, had a significant association only in the gene-alcohol drinking interaction (gene-environment interaction P (PG×E)=4.39×10(-11) and PG×E=4.80×10(-8), respectively). Variants at the 4q23 locus, which includes the ADH cluster, each had a significant interaction with alcohol drinking in their association with ESCC risk (PG×E=2.54×10(-7) to PG×E=3.23×10(-2)). We confirmed the known association of the ALDH2 locus on 12q24 to ESCC, and a joint analysis showed that drinkers with both of the ADH1B and ALDH2 risk alleles had a fourfold increased risk for ESCC compared to drinkers without these risk alleles. Our results underscore the direct genetic contribution to ESCC risk, as well as the genetic contribution to ESCC through interaction with alcohol consumption.
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Affiliation(s)
- Chen Wu
- State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Abstract
The hypothalamus is one of the master regulators of various physiological processes, including energy balance and nutrient metabolism. These regulatory functions are mediated by discrete hypothalamic regions that integrate metabolic sensing with neuroendocrine and neural controls of systemic physiology. Neurons and nonneuronal cells in these hypothalamic regions act supportively to execute metabolic regulations. Under conditions of brain and hypothalamic inflammation, which may result from overnutrition-induced intracellular stresses or disease-associated systemic inflammatory factors, extracellular and intracellular environments of hypothalamic cells are disrupted, leading to central metabolic dysregulations and various diseases. Recent research has begun to elucidate the effects of hypothalamic inflammation in causing diverse components of metabolic syndrome leading to diabetes and cardiovascular disease. These new understandings have provocatively expanded previous knowledge on the cachectic roles of brain inflammatory response in diseases, such as infections and cancers. This review describes the molecular and cellular characteristics of hypothalamic inflammation in metabolic syndrome and related diseases as opposed to cachectic diseases, and also discusses concepts and potential applications of inhibiting central/hypothalamic inflammation to treat nutritional diseases.
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Affiliation(s)
- Dongsheng Cai
- Department of Molecular Pharmacology, Diabetes Research Center, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
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