A pertussis/choleratoxin-sensitive N protein may mediate chemoattractant receptor signal transduction.

Journal Article (Journal Article)

Chemoattractant receptors on phagocytic leukocytes utilize a guanine nucleotide regulatory (N) protein to activate phospholipase C and subsequent biological responses. Since pertussis toxin inhibits activation of leukocytes by chemoattractants and ribosylates a ca. 40 kD protein in these cells it had generally been assumed that chemoattractant receptors are coupled to Ni. We now report that human polymorphonuclear leukocytes (PMNs), monocytes, and the myeloid HL-60 and U937 cell lines, but not erythrocytes or bovine brain contain a ca. 40 kD protein which is a substrate for ADP ribosylation by choleratoxin (CT). This N protein, termed Nc for chemotaxis-related N protein, comigrates with the ca. 40 kD PT substrate during one-dimensional gel electrophoresis. In vivo treatment of PMNs with PT or CT reduced high affinity binding of chemoattractants to membrane preparations from the cells, implying that chemoattractant receptors are coupled to an N protein which is a substrate for both PT and CT. We suggest that Nc rather than Ni couples chemoattractant receptors to phospholipase C.

Full Text

Duke Authors

Cited Authors

  • Verghese, M; Uhing, RJ; Snyderman, R

Published Date

  • July 31, 1986

Published In

Volume / Issue

  • 138 / 2

Start / End Page

  • 887 - 894

PubMed ID

  • 3017343

International Standard Serial Number (ISSN)

  • 0006-291X

Digital Object Identifier (DOI)

  • 10.1016/s0006-291x(86)80579-4


  • eng

Conference Location

  • United States