Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have presented evidence indicating that P2-purinergic receptors may activate the polyphosphoinositide-phospholipase C in HL60 cells via the mediation of a pertussis-toxin-sensitive GTP-binding protein, which also mediates the actions of chemotactic peptide receptors in these and other phagocytic white blood cells. However, our data also suggest that these same receptors can be coupled to the phospholipase via an additional pertussis-toxin-insensitive mechanism. This latter finding raises the possibility that undifferentiated HL60 cells express two distinct GTP-binding proteins coupled to phospholipase C; one of these is very likely to be the GHL/GC protein recently isolated from this cell line. Significantly, the data of Oinuma et al. and Falloon et al. indicate that expression of the 40-kDa alpha-subunit/toxin substrate increases upon differentiation of HL60 cells along the granulocyte pathway. It would be interesting to determine whether expression of the putative pertussis-toxin-insensitive G-protein decreases with differentiation of these and other myelomonocytic progenitor cells. Such studies, which are now in progress, should be facilitated by the fact that the P2-purinergic receptors appear to be expressed in myelopoietic cells from the promyelocytic/promonocytic stages through the terminally differentiated stages represented by circulating neutrophils and monocytes.
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PMID:Activation of the inositol phospholipid signaling system by receptors for extracellular ATP in human neutrophils, monocytes, and neutrophil/monocyte progenitor cells. 285 20

A GTP-binding protein serving as the specific substrate of islet-activating protein (IAP), pertussis toxin, was partially purified from human leukemic (HL-60) cells that had been differentiated into neutrophil type. The partially purified protein, referred to as GHL, predominantly consisted of at least two polypeptides with molecular masses of 40,000 daltons (alpha) and 36,000 or 35,000 daltons (beta). The structure was similar to Gi or Go previously purified from rat brain as an alpha beta gamma-heterotrimeric IAP substrate (Katada, T., Oinuma, M., and Ui, M. (1986) J. Biol. Chem. 261, 8182-8191), although the existence of the gamma of GHL was unclear. The 40,000-dalton polypeptide contained the site for IAP-catalyzed ADP-ribosylation and the binding site for guanine nucleotide with a high affinity. The 36,000- and 35,000-dalton polypeptides were cross-reacted with the affinity-purified antibody raised against the beta of brain Gi and Go. Limited proteolysis with trypsin and immunoblot analyses with the use of the affinity-purified antibodies raised against the alpha of brain Gi or Go indicated that the alpha of GHL was different from the alpha of Gi or Go. Kinetics of guanosine 5'-(3-O-thio)triphosphate (GTP gamma S) binding to GHL was also quite different from that to brain Gi or Go. Incubation of GHL with GTP gamma S resulted in a resolution into GTP gamma S-bound alpha and beta(gamma) thus purified had abilities to inhibit a membrane-bound adenylate cyclase activity and to associate with the alpha of brain IAP substrate in a fashion similar to the beta gamma of brain IAP substrates, suggesting that there were no significant differences in the biological activities between the beta(gamma) of GHL and those of Gi or Go. Physiological roles of the new GTP-binding protein, GHL, purified from the neutrophil-like cells in receptor-mediated signal transduction are discussed.
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PMID:A new GTP-binding protein in differentiated human leukemic (HL-60) cells serving as the specific substrate of islet-activating protein, pertussis toxin. 311 Jan 46