The Sulfogalactose Moiety of Sulfoglycosphingolipids Serves as a Mimic of Tyrosine Phosphate in Many Recognition Processes

The recognition of phosphate and sulphate esters of tyrosine residues has been studied employing antisera with specificity for tyrosine phosphate, and the enzymes aryl sulphatase, and acid and alkaline phosphatases. The ability of tyrosine phosphate, and of phosphate esters of phenol, to inhibit the antiserum was pH dependent. The capacity to effect inhibition appeared to correlate with alterations in the ionisation of the inhibitor. Moreover, the antisera with reactivity for tyrosine phosphate had no reactivity with tyrosine sulphate or sulphate esters of phenol at any pH value studied. The enzymes alkaline phosphatase, acid phosphatase, and aryl sulphatase were also studied. The phosphatases were found not to hydrolyse sulphate ester containing substrate analogues at any pH value in the range 5.0–9.0. In contrast, aryl sulphatase appeared to hydrolyse phosphate esters at pH 5.0 and 7.0, but not at pH 9.0.

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Laboratory studies of the effect of Pall extracorporeal leucocyte filters LG6 and AV6 on patients undergoing coronary bypass grafts

Perfusion ◽

10.1177/026765919601100104 ◽

1996 ◽

Vol 11 (1) ◽

pp. 29-37 ◽

Cited By ~ 27

Author(s):

PJ Thurlow ◽

L. Doolan ◽

R. Sharp ◽

M. Sullivan ◽

B. Smith ◽

...

Keyword(s):

Extracorporeal Circulation ◽

Artery Bypass ◽

Coronary Bypass ◽

Coronary Artery Bypass Grafts ◽

Laboratory Studies ◽

Bypass Grafts ◽

Indirect Measure ◽

Coronary Bypass Grafts ◽

Activation Antigens ◽

Tyrosine Phosphate

A total of 14 patients with ischaemic heart disease undergoing coronary artery bypass grafts were studied for the effect of AV6 control filter and LG6 neutrophil filter, used in the extracorporeal circulation, on different laboratory parameters. There was no statistical difference between the effects of AV6 and LG6 filters on total white cells, neutrophils, monocytes, lymphocytes, platelets or haemoglobin. The expression of neutrophil activation antigens identified with a panel of monoclonal antibodies demonstrated that for the LG6 filter the leucocyte tyrosine phosphate CD45Ro fell during the procedure, whilst there were no significant changes in any of the other neutrophil antigens. The AV6 filter did not significantly diminish the expression of any of the neutrophil antigens. An indirect measure of superoxide production using Dihydrorhodamine 123 identified that the more activated cells appeared to be depleted across the LG6 filter which was not evident with the AV6 filter. These studies indicate that the LG6 is not capable of significantly depleting the neutrophil load generated during extracorporeal circulation but may be capable of selectively removing the more activated forms.

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Identification of candidate genes that underlie the QTL on chromosome 1 that mediates genetic differences in stress-ethanol interactions

Physiological Genomics ◽

10.1152/physiolgenomics.00114.2014 ◽

2015 ◽

Vol 47 (8) ◽

pp. 308-317 ◽

Cited By ~ 12

Author(s):

Melloni N. Cook ◽

Jessica A. Baker ◽

Scott A. Heldt ◽

Robert W. Williams ◽

Kristin M. Hamre ◽

...

Keyword(s):

Candidate Genes ◽

Genome Wide Association Study ◽

Zinc Finger Protein ◽

Genetic Differences ◽

Chromosome 1 ◽

Protein Tyrosine ◽

Finger Protein ◽

Genome Wide ◽

Trait Locus ◽

Tyrosine Phosphate

Alcoholism, stress, and anxiety are strongly interacting heritable, polygenetic traits. In a previous study, we identified a quantitative trait locus (QTL) on murine chromosome (Chr) 1 between 23.0 and 31.5 Mb that modulates genetic differences in the effects of ethanol on anxiety-related phenotypes. The goal of the present study was to extend the analysis of this locus with a focus on identifying candidate genes using newly available data and tools. Anxiety-like behavior was evaluated with an elevated zero maze following saline or ethanol injections (1.8 g/kg) in C57BL/6J, DBA2J, and 72 BXD strains. We detected significant effects of strain and treatment and their interaction on anxiety-related behaviors, although surprisingly, sex was not a significant factor. The Chr1 QTL is specific to the ethanol-treated cohort. Candidate genes in this locus were evaluated using now standard bioinformatic criteria. Collagen 19a1 ( Col19a1) and family sequence 135a ( Fam135a) met most criteria but have lower expression levels and lacked biological verification and, therefore, were considered less likely candidates. In contrast, two other genes, the prenylated protein tyrosine phosphate family member Ptp4a1 (protein tyrosine phosphate 4a1) and the zinc finger protein Phf3 (plant homeoDomain finger protein 3) met each of our bioinformatic criteria and are thus strong candidates. These findings are also of translational relevance because both Ptp4a1 and Phf3 have been nominated as candidates genes for alcohol dependence in a human genome-wide association study. Our findings support the hypothesis that variants in one or both of these genes modulate heritable differences in the effects of ethanol on anxiety-related behaviors.

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Disruption of protein tyrosine phosphate homeostasis in bronchial epithelial cells exposed to oil fly ash

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1997.272.3.l426 ◽

1997 ◽

Vol 272 (3) ◽

pp. L426-L432 ◽

Cited By ~ 20

Author(s):

J. M. Samet ◽

J. Stonehuerner ◽

W. Reed ◽

R. B. Devlin ◽

L. A. Dailey ◽

...

Keyword(s):

Fly Ash ◽

Epithelial Cells ◽

Phosphatase Activity ◽

Tyrosine Phosphatase ◽

Bronchial Epithelial Cells ◽

Phosphate Homeostasis ◽

Bronchial Epithelial ◽

Protein Tyrosine ◽

Oil Fly Ash ◽

Tyrosine Phosphate

Residual oil fly ash (ROFA) is a toxic air pollutant that we have previously shown induces inflammatory mediator expression in human bronchial epithelial cells. To identify intracellular signaling mechanisms activated by ROFA, we studied its effect on protein tyrosine phosphate metabolism in the human bronchial epithelial cell line BEAS. Noncytotoxic levels of ROFA induced significant dose- and time-dependent increases in protein tyrosine phosphate levels in BEAS cells. ROFA-induced increases in protein phosphotyrosines were associated with its soluble fraction and were mimicked by vanadyl [V(IV)]- and vanadate [V(V)]-containing solutions. Ferrous, ferric, and nickel (II) ion solutions failed to increase phosphotyrosine levels. Tyrosine phosphatase activity, which was known to be inhibited by vanadium ions, was markedly diminished after ROFA treatment. Tyrosine kinase activity was unaffected. We conclude that ROFA exposure induces vanadium ion-mediated inhibition of tyrosine phosphatase activity, leading to accumulation of protein phosphotyrosines in BEAS cells. These findings demonstrate that ROFA exposure disrupts protein tyrosine phosphate homeostasis in BEAS cells and suggest a possible mechanism that leads to increased synthesis of proinflammatory proteins in airway epithelial cells exposed to PM10.

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Ionenaustausch-chromatographische Untersuchungen über die freien Aminosäuren und deren Derivate in Drosophila melanogaster

Zeitschrift für Naturforschung B ◽

10.1515/znb-1965-0407 ◽

1965 ◽

Vol 20 (4) ◽

pp. 307-312 ◽

Cited By ~ 29

Author(s):

P. S. Chen ◽

F. Hanimann

Keyword(s):

Amino Acids ◽

Drosophila Melanogaster ◽

Amino Acid ◽

Partition Chromatography ◽

Automatic Amino Acid Analyzer ◽

Amino Butyric Acid ◽

Amino Acid Analyzer ◽

Tyrosine Phosphate ◽

Distinct Separation ◽

Metabolic Significance

By using the automatic amino acid analyzer (model 120 B, Beckman) the free ninhydrin-positive components in the methanol extracts of Drosophila melanogaster were fractionated. Compared to the conventional paper partition chromatography the great advantage of this technique is the distinct separation of such amino acids like leucine, isoleucine, phenylalanine, valine, methionine, γ-amino-butyric acid as well as the basic components ornithine, lysine, histidine and arginine. Furthermore, the occurrence of phosphoserine, tyrosine phosphate, ethanolamine, phosphoethanolamine and glycerophosphoethanolamine was identified. The metabolic significance of these substances is discussed.

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