Setaria cervidual specific phosphatase: characterization and its effect on eosinophil degranulation

Parasitology ◽  
2009 ◽  
Vol 136 (8) ◽  
pp. 895-904 ◽  
Author(s):  
S. RATHAUR ◽  
R. RAI ◽  
E. SRIKANTH ◽  
S. SRIVASTAVA
Keyword(s):  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Gel Filtration ◽  
Specific Protein ◽  
Enzyme Concentration ◽  
Cross Reactivity ◽  
Filarial Parasite ◽  
Significant Activity ◽  
Protein Tyrosine

SUMMARYSetaria cervi, a bovine filarial parasite contains significant acid phosphatase (AcP) activity in its various life stages. Two forms of AcP were separated from somatic extract of adult female parasite using cation exchange, gel filtration and concavalin affinity chromatography. One form having a molecular mass of 79 kDa was characterized as dual specific protein tyrosine phosphatase (ScDSP) based on substrate specificity and inhibition studies. With various substrates tested, it showed significant activity in the order of phospho-L-tyrosine>pNPP>ADP>phospho-L-serine. Inhibition by orthovanadate, fluoride, molybdate, and zinc ions further confirms protein tyrosine phosphatase nature of the enzyme. Km and Vmax determined with various substrates were found to be 16·66 mM, 25·0 μM/ml/min with pNPP; 20·0 mM, 40·0 μM/ml/min with phospho-L-tyrosine and 27·0 mM, 25·0 μM/ml/min with phospho-L-serine. KIwith pNPP and sodium orthovanadate (IC5033·0 μM) was calculated to be 50·0 mM. Inhibition with pHMB, silver nitrate, DEPC and EDAC suggested the presence of cysteine, histidine and carboxylate residues at its active site. Cross-reactivity withW. bancrofti-infected sera was demonstrated by Western blotting. ScDSP showed elevated levels of IgE in chronic filarial sera using ELISA. Underin vitroconditions, ScDSP resulted in increased effector function of human eosinophils when stimulated by IgG, which showed a further decrease with increasing enzyme concentration. Results presented here suggest thatS. cerviDSP should be further studied to determine its role in pathogenesis and the persistence of filarial parasite.

Analysis of in vitro interactions of protein tyrosine phosphatase 1B with insulin receptors

2001 ◽  
Vol 173 (1-2) ◽  
pp. 109-120 ◽  
Author(s):  
Xin-Yuan Wang ◽  
Katrin Bergdahl ◽  
Anna Heijbel ◽  
Charlotta Liljebris ◽  
John E. Bleasdale
Keyword(s):  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Insulin Receptors ◽  
Protein Tyrosine Phosphatase 1B ◽  
Protein Tyrosine ◽  
In Vitro Interactions

Protein-tyrosine phosphatase activity of CD45 is activated by sequential phosphorylation by two kinases

1994 ◽  
Vol 14 (8) ◽  
pp. 5523-5532
Author(s):  
D R Stover ◽  
K A Walsh
Keyword(s):  
T Cell Activation ◽  
Protein Tyrosine Phosphatase ◽  
Time Course ◽  
Cell Activation ◽  
Regulatory Mechanism ◽  
Transmembrane Protein ◽  
Tyrosine Phosphatase ◽  
Protein Tyrosine

We describe a potential regulatory mechanism for the transmembrane protein-tyrosine phosphatase CD45. Phosphorylation on both tyrosine and serine residues in vitro results in an activation of CD45 specifically toward one artificial substrate but not another. The activation of these kinases appears to be order dependent, as it is enhanced when phosphorylation of tyrosine precedes that of serine but phosphorylation in the reverse order yields no activation. Any of four protein-tyrosine kinases tested, in combination with the protein-serine/threonine kinase, casein kinase II, was capable of mediating this activation in vitro. The time course of phosphorylation of CD45 in response to T-cell activation is consistent with the possibility that this regulatory mechanism is utilized in vivo.

scholarly journals Six New 3,5-Dimethylcoumarins from Chelonopsis praecox, Chelonopsis odontochila and Chelonopsis pseudobracteata

2021 ◽  
Author(s):  
Chang-An Geng ◽  
Zhen-Tao Deng ◽  
Qian Huang ◽  
Chun-Lei Xiang ◽  
Ji-Jun Chen
Keyword(s):  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
2D Nmr ◽  
Cell Protein ◽  
Protein Tyrosine Phosphatase 1B ◽  
Protein Tyrosine ◽  
Aerial Parts ◽  
Spectroscopic Analyses ◽  
New Compounds

AbstractTen 3,5-dimethylcoumarins (1–6 and 8‒11) involving six new ones (1–6), together with a known 3-methylcoumarin (7), were isolated from the aerial parts of three Chelonopsis plants, C. praecox, C. odontochila, and C. pseudobracteata. The structures of the new compounds were determined by extensive HRESIMS, 1D and 2D NMR spectroscopic analyses. According to the substitution at C-5, these coumarins were classified into 5-methyl, 5-hydroxymethyl, 5-formyl, and 5-nor types. All the isolates were assayed for their inhibition on α-glucosidase, protein tyrosine phosphatase 1B, and T-cell protein tyrosine phosphatase in vitro. Graphic Abstract

scholarly journals Simulasi Docking Senyawa Aglikon Kurkuligosida A dan Turunannya pada Protein Tyrosine Phosphatase 1B (PTP1B)

2019 ◽  
Vol 16 (2) ◽  
pp. 216
Author(s):  
Nursamsiar Nursamsiar ◽  
Akbar Awaluddin ◽  
Megawati Megawati ◽  
Yulita M. Soko ◽  
Muhammad Aswad
Keyword(s):  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Protein Tyrosine Phosphatase 1B ◽  
Protein Tyrosine ◽  
Autodock 4.2 ◽  
Diabetes Melitus

Senyawa aglikon kurkuligosida A memiliki struktur yang mirip dengan senyawa licoagrochalcone yang terbukti memiliki aktivitas penghambatan yang kuat secara in vitro pada Protein Tyrosine Phosphatase 1B (PTP1B), yang dianggap sebagai target terapeutik untuk pengobatan diabetes melitus tipe 2. Penelitian ini bertujuan untuk mengetahui interaksi antara senyawa aglikon kurkuligosida A dan turunannya dengan PTP1B menggunakan metode simulasi docking. Simulasi docking dilakukan dengan menggunakan perangkat lunak AutoDock 4.2. Hasil docking menunjukan semua senyawa yang diuji dapat berinteraksi dengan sisi aktif PTP1B. Interaksi terbaik ditunjukkan oleh senyawa 31 (3,5-dihidroksibensil-3,5-dinitrobenzoate), senyawa 39 (3,5-dihidroksibensil-4-nitrobenzoate) dan senyawa 52 (4-hidroksibensil-4-nitro bensoat) dengan nilai energi bebas ikatan berturut-turut –9,40 kkal/mol ; –9,19 kkal/mol dan –9,03 kkal/mol. Ketiga senyawa tersebut memiliki interaksi dengan sisi aktif PTP1B dengan residu asam amino Ser216 dan Arg221. Semua senyawa turunan aglikon kurkuligosida A yang diuji juga memiliki pola pengikatan yang sama dengan ligan alami pada PTP1B.

In Vitro Enzymatic Assays of Protein Tyrosine Phosphatase 1B

2001 ◽  
Vol 13 (1) ◽  
Author(s):  
Thomas Lubben ◽  
Jill Clampit ◽  
Michael Stashko ◽  
James Trevillyan ◽  
Michael R. Jirousek
Keyword(s):  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Protein Tyrosine Phosphatase 1B ◽  
Enzymatic Assays ◽  
Protein Tyrosine

Selective Inhibitors of the Protein Tyrosine Phosphatase SHP2 Block Cellular Motility and Growth of Cancer Cells in vitro and in vivo

ChemMedChem ◽  
2015 ◽  
Vol 10 (5) ◽  
pp. 815-826 ◽  
Author(s):  
Stefanie Grosskopf ◽  
Chris Eckert ◽  
Christoph Arkona ◽  
Silke Radetzki ◽  
Kerstin Böhm ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Cellular Motility ◽  
Selective Inhibitors ◽  
Protein Tyrosine

scholarly journals Identification of Increased Protein Tyrosine Phosphatase Activity in Polycythemia Vera Erythroid Progenitor Cells

Blood ◽  
1997 ◽  
Vol 90 (2) ◽  
pp. 651-657 ◽  
Author(s):  
Xingwei Sui ◽  
Sanford B. Krantz ◽  
Zhizhuang Zhao
Keyword(s):  
Polycythemia Vera ◽  
Progenitor Cells ◽  
Protein Tyrosine Phosphatase ◽  
Tyrosine Phosphatase ◽  
Gel Filtration ◽  
Erythroid Progenitors ◽  
Erythroid Progenitor ◽  
Normal Cells ◽  
Protein Tyrosine ◽  
Erythroid Progenitor Cells

Abstract Polycythemia vera (PV) is a clonal hematologic disease characterized by hyperplasia of the three major bone marrow lineages. PV erythroid progenitor cells display hypersensitivity to several growth factors, which might be caused by an abnormality of tyrosine phosphorylation. In the present study, we have investigated protein tyrosine phosphatase (PTP) activity in highly purified erythroid progenitor cells and found that the total PTP activity in the PV cells was twofold to threefold higher than that in normal cells. Protein separation on anion-exchange and gel-filtration columns showed that the increased activity was due to a major PTP eluted at approximately 170 kD. This enzyme was sensitive to PTP inhibitors and it did not cross-react with antibodies to SHP-1, SHP-2, or CD45. Subcellular fractionation showed that the PTP localized with the membrane fraction, where its activity was increased by threefold in PV erythroid progenitors when compared with normal cells. As the erythroid progenitors progressively matured, activity of the PTP declined rapidly in the normal cells but at a much slower rate in the PV cells. These studies suggest that a potentially novel membrane or membrane-associated PTP, representing a major PTP activity, may have an important role in proliferation and/or survival of human erythroid progenitors and that its hyperactivation in PV erythroid progenitors might be responsible for the increased erythropoiesis in PV patients.

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