FIBRILLAR STRUCTURES IN THE CYTOPLASM OF CHAOS CHAOS

Although a number of studies of the finc structure of fixed amcbae have appeared (Pappas, 1959; Mercer, 1959; Roth, 1960; Brandt and Pappas, 1962), fibrillar structures in the cytoplasm have not been reported. This is surprising in view of thc fact that several current theories of ameboid movemcnt postulate the cxistence of contractile and hence presumably fibrillar material. This discrepancy bctween what is thought to cxist in living amebae and what has so far been found in fixed specimens has recently been emphasized (Goldacre, 1961; Pitelka, 1963). Furthermore, thcre is mounting evidence from other Wpes of studics that contractilc structures exist in amebae. To cite only a few cxamples, Kriszat (1949) and Goldacre and Lorch (1950) found that adenosine triphosphate produced characteristic changes in thc cytoplasmic consistcncy of amebae. Simard-Duquesne and Couillard (1962) reported that a glycerinated ameba preparation contracted upon addition of adenosine triphosphatc and magncsium ion. Most recently, Wolpert, Thompson, and O'Neil l (1964) have provided electron microscope evidence for fibrillar material in preparations of centrifuged ameba cytoplasm induced to gelate by addition of adenosine triphosphate. The present communicat ion reports the finding of extensive areas of fibrillar material in sections of amebae fixed after exposure to Alcian Blue, a dye which binds irreversibly to the cell surface and induces pinocytosis at room temperature.

[1]  T. Lentz.  Electron-Microscopic Structure of Protozoa , 1964, The Yale Journal of Biology and Medicine.

[2]  L. Wolpert,et al.  Studies on the Isolated Membrane and Cytoplasm of Amoeba proteus in Relation to Ameboid Movement , 1964 .

[3]  P. Couillard,et al.  Ameboid movement, I. Reactivation of glycerinated models of Amoeba proteus with adenosinetriphosphate. , 1962, Experimental cell research.

[4]  P. Brandt,et al.  AN ELECTRON MICROSCOPIC STUDY OF PINOCYTOSIS IN AMEBA , 1962, The Journal of cell biology.

[5]  R. A. Jenkins,et al.  CONDITIONS FOR OSMIUM FIXATION OF FIBRILS IN THE MITOTIC APPARATUS , 1962 .

[6]  A. Claude,et al.  Fixation of nuclear structures by unbuffered solutions of osmium tetroxide in slightly acid distilled water , 1962 .

[7]  E. Daniels,et al.  Electron microscopic studies of mitosis in amebae. II. The giant ameba Pelomyxa carolinensis. , 1962 .

[8]  R. Goldacre.  The role of the cell membrane in the locomotion of amoebae, and the source of the motive force and its control by feedback. , 1961, Experimental cell research.

[9]  L. E. Roth.  Electron Microscopy of Pinocytosis and Food Vacuoles in Pelomyxa , 1960 .

[10]  G. Pappas.  Electron Microscope Studies on Amoebae , 1959 .

[11]  E. H. Mercer.  An electron microscopic study of Amoeba proteus , 1959, Proceedings of the Royal Society of London. Series B - Biological Sciences.

[12]  D. Marsland,et al.  Temperature-pressure experiments on amoeba proteus; plasmagel structure in relation to form and movement. , 1954, Journal of cellular and comparative physiology.

[13]  A. Pigon,et al.  Diffusion and active transport of water in amoeba Chaos chaos l. , 1952, Comptes rendus des travaux du Laboratoire Carlsberg. Serie chimique.

[14]  I. Lorch,et al.  Folding and Unfolding of Protein Molecules in Relation to Cytoplasmic Streaming, Amœboid Movement and Osmotic Work , 1950, Nature.

[15]  C. Prosser,et al.  Effect of temperature, salts, and hydrogen‐ion concentration on rupture of the plasmagel sheet, rate of locomotion, and gel/sol ratio in amoeba proteus , 1932 .