Amoeba Proteus

Filaments of Amoeba Proteus

Amoeba proteus has two types of cytoplasmic filaments that are thought to be important in cell motility, cytoplasmic streaming, and changes in cytoplasmic consistency : thin, 50-70 A wide filaments, and short, thick, 160 A wide rods (Pollard and Ito, 1970) . The thin filaments resemble the actin filaments of muscle (Hanson and Lowy, 1963), Acanthamoeba (Weihing and Korn, 1969 ; Pollard et al .,...

Membrane potentials in Amoeba proteus.

Calcium distribution in Amoeba proteus

A preliminary investigation of the distribution of cellular calcium in Amoeba proteus was undertaken. Total cellular calcium under control conditions was found to be 4.59 mmol/kg of cells. When the external Ca++ concentration is increased from the control level of 0.03 to 20 mM, a net Ca++ influx results with a new steady-state cellular calcium level being achieved in integral of 3 h. At steady...

Cytoplasmic Filaments of Amoeba Proteus

The role of filaments in consistency changes and movement in a motile cytoplasmic extract of Amoeba proteus was investigated by correlating light and electron microscopic observations with viscosity measurements. The extract is prepared by the method of Thompson and Wolpert (1963). At 0 degrees C, this extract is nonmotile and similar in structure to ameba cytoplasm, consisting of groundplasm, ...

Cytoplasmic Dna Synthesis in Amoeba Proteus

The application of electron microscope autoradiography to Amoeba proteus cells labeled with tritiated thymidine has permitted the identification of morphologically distinct particles in the cytoplasm as the sites of incorporated DNA precursor. The particles correspond to those previously described from light microscope studies, with respect to both H(3)Tdr incorporation and distribution in cent...