@article {KASLOW472, author = {HARVEY R. KASLOW and ZVI FARFEL and GARY L. JOHNSON and HENRY R. BOURNE}, title = {Adenylate Cyclase Assembled In Vitro: Cholera Toxin Substrates Determine Different Patterns of Regulation by Isoproterenol and Guanosine 5{\textquoteright}-triphosphate}, volume = {15}, number = {3}, pages = {472--483}, year = {1979}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {Genetic and biochemical evidence indicates that hormone-sensitive adenylate cyclase consists of at least three separable components: hormone receptor (R), a catalytic unit (C) that synthesizes cAMP from ATP, and one or more regulatory factors, which we have termed N, that are required for functional coupling of R and C and also for cyclase stimulation by guanyl nucleotides, NaF, and cholera toxin. The functional absence of N in a S49 lymphoma variant clone, cyc-, allows in vitro assembly of hormone-sensitive adenylate cyclase, using cyc- membranes and N components in detergent extracts from membranes of other cells (Ross, E. M. and Gilman, A. G. Proc. Nat. Acad. Sci., USA 74,3715-3719, 1977). Such cyclase systems, assembled in vitro using N components from wild type S49 cells and turkey erythrocytes, are functionally distinguishable, each resembling{\textemdash}in responses to guanyl nucleotides and isoproterenol{\textemdash}the cyclase system from which the N component was derived. Thus, the N component determines certain functional characteristics of the response to guanine nucleotides and isoproterenol. Human erythrocyte membranes, which are virtually devoid of catalytic adenylate cyclase, also contain the functional N component. Donor extracts of human and turkey erythrocytes and S49 cells contain cholera toxin substrates, by two criteria: 1. The extracts transmit effects of toxin on donor membranes to adenylate cyclase assembled in vitro using cyc- membranes; 2. Incubation with toxin plus [32P]NAD+ specifically radiolabels substrates in each type of membrane, including a peptide of Mr = 42,000, common to all three. The results are consistent with the hypothesis that this peptide participates directly in multiple functions of N. ACKNOWLEDGMENT We thank Ms. Mary Gleason for expert technical assistance.}, issn = {0026-895X}, URL = {https://molpharm.aspetjournals.org/content/15/3/472}, eprint = {https://molpharm.aspetjournals.org/content/15/3/472.full.pdf}, journal = {Molecular Pharmacology} }