Dictyostelium discoideum

Smith, C. A., Rayment, 1. X-ray structure of the magnesium (11). ADP-vanadate complex of the Dictyostelium discoideum myosin motor domain to 1.9 A resolution. Biochemistry 35 5404-5407, 1996. 

Studies in yeasts (Saccharomyces cerevisiae, Schizo-saccharomyces pombe), slime mould (,Dictyostelium discoideum), worm (Caenorhabditis elegans), fly (Drosophila melanogaster) and mammalian systems have all contributed to our understanding of TOR signalling. 

Manstein, D.J., Ruppel, K.M., Spudich, J.A. (1989). Expression and characterization of a functional myosin head fragment in Dictyostelium discoideum. Science 246, 656-658. 

Knecht, D.A., Loomis, W.F. (1987). Antisense RNA inactivation of myosin heavy chain gene expression in Dictyostelium discoideum. Science 236, 1081-1086. 

Newell, P.C., Europe-Finner, G.N., Small, N.V. (1987). Signal transduction during amoebal chemo-taxis of Dictyostelium discoideum. Microbiol. Sci. 4. 5-11. 

Phycomyces is by no means the only organism that can regulate its own growth with volatile substances. Bonner and Dodd (1962) have reported that Polysphondilium pallidum,Dictyostelium discoideum,D. mucoroides,D. purpureum have the capacity to avoid obstacles. A series of experiments has clearly shown that this orientating effect is due to a gas made by the organism. Attempts to identify this gas have been unsuccessful. 

Ingalls, H.M., Goodloe-Holland, C.M., and Luna, E.J. (1986) Junctional plasma membrane domains isolated from aggregating Dictyostelium discoideum amebae. Proc. Natl Acad. Sci. USA 83, 4779-4783. 

Simon, J.R., and Taylor, D.L. (1988) Preparation of a fluorescent analog Acetamidofluoresceinyl labeled dictyostelium discoideum a-actin. In Methods in Enzymology, (R.B. Vallee, ed.), Vol. 134, p. 47. Academic Press, San Diego. 

B. Wright, W. Simon, and T. Walsh, A kinetic model of metabolism essential to differentiation in Dictyostelium discoideum. Proc. Natl. Acad. Sci. 60, 644 651 (1968). 

Y. Tang and H. G. Othmer, Excitation, oscillations and wave propagation in a G-protein-based model of signal transduction in Dictyostelium discoideum. Philos. Trans. R. Soc. Land. B. Biol. Sci. 349, 179-195 (1995). 

A. Goldbeter and L. A. Segel, Control of developmental transitions in the cyclic AMP signaling system of Dictyostelium discoideum. Differentiation 17, 127-135 (1980). 

E. Palsson and E. C. Cox, Origin and evolution of circular waves and spirals in Dictyostelium discoideum territories. Proc. Natl. Acad. Sci. USA 93, 1151-1155 (1996). 

Actin-binding proteins ABP-50, purification, 196, 78 ABP-120, purification, 196, 79 ABP-240 purification, 196, 76 effect on actin depolymerization, 215, 74 extraction, 196, 311 isolation from Dictyostelium discoideum, 196, 70 platelet-derived actin binding proteins [characterization, 215, 58 purification, 215, 58, 64 recombination with actin, 215, 73] 30-kDa Dictyostelium discoideum actin-crosslinking protein [assays, 196, 91 preparation, 196, 84] actin-depolymerizing factor [assay, 196, 132[ DNase assay, 196, 136 platelet-derived a-actinin [characterization, 215, 58 purification, 215, 58, 70 recombination with actin, 215, 73]. 

These studies demonstrate the general mechanism of synchronization of biochemical systems, which I expect to be operative in even more complex systems, such as the mitochondrial respiration or the periodic activity of the slime mold Dictyostelium discoideum. As shown in a number of laboratories under suitable conditions mitochondrial respiration can break into self-sustained oscillations of ATP and ADP, NADH, cytochromes, and oxygen uptake as well as various ion transport and proton transport functions. It is important to note that mitochondrial respiration and oxidative phosphorylation under conditions of oscillations is open for the source, namely, oxygen, as well as with respect to a number of sink reactions producing water, carbon dioxide, and heat. 

Fig. 1. Oscillation of light scattering in Dictyostelium discoideum cell suspension.

Dictyostelium discoideum (gene MHCK A [2,14,18] strain JHIO [18] strain Ax-3 [5] two heavy chain kinases one in growth-phase cells and one in starved, developing cells [2,3] isozyme myosin II heavy chain kinase A [5,18]) [1-3, 5, 14, 18]... 

Dictyostelium discoideum (myosin II heavy chain kinase MHCK A [26] gene MHKA or MHCKA, myosin heavy chain kinase A [13]) [13, 26]... 

Dictyostelium discoideum (gene MHCK, myosin heavy chain kinase [13])... 

Dictyostelium discoideum (myosin I heavy chain kinase [19]) [19]... 

Dictyostelium discoideum (gene MHCK C, myosin II heavy chain kinase C... 

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