Plasmodium of Physarum

Physarum plasmodium that has migrated from a small block of nutrient agar onto the surface of a nutrient agar plate. At 22C, the plasmodium can grow to cover the whole plate in about 3 days. Movement occurs as the result of cytoplasmic streaming through the "veins" that are clearly visible in this photo; the direction of streaming reverses approximately every 30 seconds ("shuttle-streaming"). This single giant cell contains millions of nuclei, all of which go through the various stages of the cell cycle (including mitosis) synchronously.

Unpublished image courtesy of Juliet Bailey.

References:

1. Burland,T.G., Solnica-Krezel,L., Bailey,J., Cunningham,D.B. and Dove,W.F. (1993). Patterns of inheritance, development and the mitotic cycle in the protist Physarum polycephalum. Advances in Microbial Physiology. 35: 1-69.

2. Bailey,J. (1995). Plasmodium development in the myxomycete Physarum polycephalum: genetic control and cellular events. Microbiology. 14: 2355-2365.