Evidence for a Macromolecular Effector of Cell Differentiation in Dictyostelium Discoideum Amoebae
Upon depletion of their food supply, myxamoebae undertake their developmental program, the first stage of which is marked by the aggregation of cells toward central collection points. Aggregation follows a period of starvation called interphase, during which cells differentiate into aggregation-competent amoebae(7): they attain an elongated morphology, move chemotactically toward their neighboring cells (4), and form specific cell-cell contacts (6) which appear to require membrane components (contact sites A) present specifically on starved cells (3). Movement of amoebae is directed by an acrasin (4), cAMP (2, 14), which starved cells rhythmically release into the media (18) . The response of cells to the chemotactic signal appears to involve surface cAMP-binding receptors (15) which probably function in the stimulation of cAMP synthesis and emission (17, 19, 20).
KeywordsCell Aggregation Dictyostelium Discoideum Phosphodiesterase Activity Chemotactic Signal cAMP Synthesis
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- 5.DARMON, M., BRACHET, P. and PEREIRA DA SILVA, L. H., Proc. Nat. Acad. Sci. USA (1975), in press.Google Scholar
- 9.GERISCH, G., MALCHOW, D. , HUESGEN, A., NANJUNDIAH, V., ROOS, W. and WICK, U., Proceedings of the 1975 ICN-UCLA Symposium on Developmental Biology (D. McMahon and C. F. Fox, eds) W. A. Benjamin (1975).Google Scholar
- 11.GILBERT, L. I., The Hormones (G. Pincus, K. V. Thimann and E. B. Ashwood, eds) Vol. 4 (1964) 67.Google Scholar
- 12.HARRIS, R. J. C. (ed) Biological Organization at the Cellular and Supercellular Level. Academic Press, N. Y. (1963).Google Scholar
- 13.KLEIN, C, J. Biol. Chem. (1975) in press.Google Scholar
- 18.SCHAFFER, B. M., Advances in Morphogenesis 2 (1962) 109.Google Scholar