Applying the SPOT peptide synthesis procedure to the study of protein tyrosine phosphatase substrate specificity: probing for the heavenly match in vitro

PTP-PEST is a ubiquitously expressed, cytosolic, mammalian protein tyrosine phosphatase (PTP) which exhibits high specific activity in vitro. We have investigated the substrate specificity of PTP-PEST by a novel substrate-trapping approach in combination with in vitro dephosphorylation experiments. We initially identified a prominent 130-kDa tyrosine-phosphorylated protein in pervanadate-treated HeLa cell lysates which was preferentially dephosphorylated by PTP-PEST in vitro. In order to identify this potential substrate, mutant (substrate-trapping) forms of PTP-PEST were generated which lack catalytic activity but retain the ability to bind substrates. These mutant proteins associated in stable complexes exclusively with the same 130-kDa protein, which was identified as p130(cas) by immunoblotting. This exclusive association was observed in lysates from several cell lines and in transfected COS cells, but was not observed with other members of the PTP family, strongly suggesting that p130(cas) represents a major physiologically relevant substrate for PTP-PEST. Our studies suggest potential roles for PTP-PEST in regulation of p130(cas) function. These functions include mitogen- and cell adhesion-induced signalling events and probable roles in transformation by various oncogenes. These results provide the first demonstration of a PTP having an inherently restricted substrate specificity in vitro and in vivo. The methods used to identify p130(cas) as a specific substrate for PTP-PEST are potentially applicable to any PTP and should therefore prove useful in determining the physiological substrates of other members of the PTP family.

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

Molecular and Cellular Endocrinology ◽

10.1016/s0303-7207(00)00402-0 ◽

2001 ◽

Vol 173 (1-2) ◽

pp. 109-120 ◽

Cited By ~ 18

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

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A P387L Variant in Protein Tyrosine Phosphatase-1B (PTP-1B) Is Associated With Type 2 Diabetes and Impaired Serine Phosphorylation of PTP-1B In Vitro

Diabetes ◽

10.2337/diabetes.51.1.1 ◽

2001 ◽

Vol 51 (1) ◽

pp. 1-6 ◽

Cited By ~ 74

Author(s):

S. M. Echwald ◽

H. Bach ◽

H. Vestergaard ◽

B. Richelsen ◽

K. Kristensen ◽

...

Keyword(s):

Type 2 Diabetes ◽

Protein Tyrosine Phosphatase ◽

Tyrosine Phosphatase ◽

Serine Phosphorylation ◽

Protein Tyrosine Phosphatase 1B ◽

Protein Tyrosine ◽

Ptp 1B

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

Molecular and Cellular Biology ◽

10.1128/mcb.14.8.5523-5532.1994 ◽

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.

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Both cell-surface carbohydrates and protein tyrosine phosphatase are involved in the differentiation of astrocytes in vitro

Glia ◽

10.1002/1098-1136(200010)32:1<60::aid-glia60>3.0.co;2-5 ◽

2000 ◽

Vol 32 (1) ◽

pp. 60-70 ◽

Cited By ~ 11

Author(s):

Tasuku Sasaki ◽

Tamao Endo

Keyword(s):

Cell Surface ◽

Protein Tyrosine Phosphatase ◽

Tyrosine Phosphatase ◽

Protein Tyrosine ◽

Surface Carbohydrates

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

Natural Products and Bioprospecting ◽

10.1007/s13659-021-00318-9 ◽

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

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

PHARMACY Jurnal Farmasi Indonesia (Pharmaceutical Journal of Indonesia) ◽

10.30595/pharmacy.v16i2.5734 ◽

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.

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