guanylyl-imidodiphosphate has been researched along with Leukemia--Promyelocytic--Acute* in 1 studies
1 other study(ies) available for guanylyl-imidodiphosphate and Leukemia--Promyelocytic--Acute
| Article | Year |
|---|---|
Differential cholera-toxin- and pertussis-toxin-catalysed ADP-ribosylation of G-proteins coupled to formyl-peptide and leukotriene B4 receptors.
N-Formylmethionyl-leucyl-phenylalanine (fMet-Leu-Phe) and leukotriene B4 (LTB4) induce disparate second-messenger generation and functional responses in neutrophils and HL-60 granulocytes. Receptors for these chemoattractants couple to a common pool of G-proteins which are substrates for both pertussis-toxin- and cholera-toxin-catalysed ADP-ribosylation. The hypothesis that formyl-peptide and LTB4 receptors induce different receptor-specific conformations of activated G-proteins was tested. The ability of pertussis toxin and cholera toxin to ADP-ribosylate G(i) proteins coupled to formyl-peptide or LTB4 receptors in membranes isolated from HL-60 granulocytes was used to assess the conformational state of the alpha subunits. Cholera-toxin-catalysed ADP-ribosylation of alpha 40 (40 kDa alpha subunit) was inhibited by guanosine 5'-[beta gamma-imido]triphosphate and GDP in a concentration-dependent manner. Addition of fMet-Leu-Phe, but not LTB4, re-established cholera-toxin labelling of alpha 40 in the presence of either guanine nucleotide. In the absence of guanine nucleotides, fMet-Leu-Phe and C5a enhanced cholera-toxin-catalysed labelling of alpha 40, whereas LTB4 and platelet-activating factor had no effect. Preincubation with fMet-Leu-Phe, but not LTB4, inhibited pertussis-toxin labelling of alpha 40 in the presence of guanosine 5'-[gamma-thio]triphosphate and in the absence of guanine nucleotides. Preincubation with fMet-Leu-Phe or LTB4 enhanced pertussis-toxin labelling of alpha 40 in the presence of GDP. These data suggest that activated G(i) proteins coupled to formyl-peptide and LTB4 receptors exist in different conformations determined by the receptor with which they interact. Topics: Adenosine Diphosphate Ribose; Cholera Toxin; GTP-Binding Proteins; Guanosine Diphosphate; Guanylyl Imidodiphosphate; Humans; Leukemia, Promyelocytic, Acute; Leukotriene B4; N-Formylmethionine Leucyl-Phenylalanine; NAD; Pertussis Toxin; Receptors, Formyl Peptide; Receptors, Immunologic; Receptors, Leukotriene B4; Tumor Cells, Cultured; Virulence Factors, Bordetella | 1993 |