A Ca2+ transport system associated with the plasma membrane of Dictyostelium discoideum is activated by different chemoattractant receptors

doi:10.1083/jcb.112.1.103

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A Ca2+ transport system associated with the plasma membrane of Dictyostelium discoideum is activated by different chemoattractant receptors

JL Milne and MB Coukell
Department of Biology, York University, Canada.

Amebae of Dictyostelium exhibit a transient uptake of extracellular Ca2+ approximately 5 s after activation of surface folate or cAMP receptors (Bumann, J., B. Wurster, and D. Malchow. 1984. J. Cell Biol. 98:173-178). To further characterize these Ca2+ entry systems, we analyzed 45Ca2+ uptake by resting and activated amebae. Like the surface chemoreceptors, folate- and cAMP-induced Ca2+ uptake responses were developmentally regulated; the former response was evident in vegetative but not aggregation-competent cells, whereas the latter response displayed the opposite pattern of expression. In contrast, other characteristics of these Ca2(+)-uptake pathways were remarkably similar. Both systems (a) exhibited comparable kinetic properties, (b) displayed a high specificity for Ca2+, and (c) were inhibited effectively by Ruthenium Red, sodium azide, and carbonylcyanide m- chlorophenyl-hydrazone. These results, together with the finding that vegetative cells transformed with a plasmid expressing the surface cAMP receptor exhibit a cAMP-induced Ca2+ uptake, suggest that different chemoreceptors activate a single Ca2+ entry pathway. Additional pharmacological and ion competition studies indicated that receptor- mediated Ca2+ entry probably does not involve a Na+/Ca2+ exchanger or voltage-activated channels. Chemoattractant binding appears to generate intracellular signals that induce activation and adaption of the Ca2(+)- uptake response. Analysis of putative signaling mutants suggests that Ca2+ entry is not regulated by the guanine nucleotide-binding (G) protein subunits G alpha 1 or G alpha 2, or by G protein-mediated changes in intracellular cAMP or guanosine 3,'5'-cyclic monophosphate (cGMP).
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Doring, V, Veretout, F, Albrecht, R, Muhlbauer, B, Schlatterer, C, Schleicher, M, Noegel, A. (1995). The in vivo role of annexin VII (synexin): characterization of an annexin VII-deficient Dictyostelium mutant indicates an involvement in Ca(2+)-regulated processes. J. Cell Sci. 108: 2065-2076 [Abstract]
Schaloske, R, Sordano, C, Bozzaro, S, Malchow, D (1995). Stimulation of calcium influx by platelet activating factor in Dictyostelium. J. Cell Sci. 108: 1597-1603 [Abstract]
Louis, J M, Ginsburg, G T, Kimmel, A R (1994). The cAMP receptor CAR4 regulates axial patterning and cellular differentiation during late development of Dictyostelium.. Genes Dev. 8: 2086-2096 [Abstract]
Dharmawardhane, S, Cubitt, A., Clark, A., Firtel, R. (1994). Regulatory role of the G alpha 1 subunit in controlling cellular morphogenesis in Dictyostelium. Development 120: 3549-3561 [Abstract]
Soede, R., Insall, R., Devreotes, P., Schaap, P (1994). Extracellular cAMP can restore development in Dictyostelium cells lacking one, but not two subtypes of early cAMP receptors (cARs). Evidence for involvement of cAR1 in aggregative gene expression. Development 120: 1997-2002 [Abstract]
Lilly, P, Wu, L, Welker, D L, Devreotes, P N (1993). A G-protein beta-subunit is essential for Dictyostelium development.. Genes Dev. 7: 986-995 [Abstract]
Saxe, C L, Ginsburg, G T, Louis, J M, Johnson, R, Devreotes, P N, Kimmel, A R (1993). CAR2, a prestalk cAMP receptor required for normal tip formation and late development of Dictyostelium discoideum.. Genes Dev. 7: 262-272 [Abstract]
Flaadt, H, Jaworski, E, Malchow, D (1993). Evidence for two intracellular calcium pools in Dictyostelium: the cAMP-induced calcium influx is directed into a NBD-Cl- and 2,5-di-(tert-butyl)1,4-hydroquinone-sensitive pool. J. Cell Sci. 105: 1131-1135 [Abstract]
Flaadt, H, Jaworski, E, Schlatterer, C, Malchow, D (1993). Cyclic AMP- and Ins(1,4,5)P3-induced Ca2+ fluxes in permeabilised cells of Dictyostelium discoideum: cGMP regulates Ca2+ entry across the plasma membrane. J. Cell Sci. 105: 255-261 [Abstract]
Hadwiger, J A, Firtel, R A (1992). Analysis of G alpha 4, a G-protein subunit required for multicellular development in Dictyostelium.. Genes Dev. 6: 38-49 [Abstract]