Video Sequences of Amoeboflagellates

The sketches below are taken from the work of Pagh and Adelman (see * at the foot of the page). The videosequences accompanying that paper were published as a laser-disk supplement to the journal and are reproduced on this site for the convenience of those without easy access to the laser-disk.
Depending on your computer and browser, these segments may take a minute or two to load, so please be patient!
The repeat amoeboflagellate transformation (RAFT - see the reference for experimental details) can be characterized as a four stage process by which amoeboid cells migrating on a moist agar surface, and then "triggered" by immersion in fluid, pass through a transformation to freely swimming flagellate cells. Such cells may either be video-recorded while transforming, or fixed at selected stages for detailed examination. Each of the following blocks shows one or more fixed cells viewed by DIC microscopy (left) or fluorescence microscopy (right), after staining with Rhodamine-Phalloidin to visualize actin. [Scale bars are not included; cells range from 8-10 um in diameter at the start of the RAFT to some 15-20 um long when fully-transformed.] Each block has a "link" to a video-sequence.

STAGE I cells are rounded, show limited motility, and remain attached to the substratum.
To view an example of such a cell, click here.

STAGE II cells develop a prominent flagellum (destined to become the most active, anterior, flagellum), and show increasing motility, but remain attached to the substratum.
To view an example of such a cell, click here.

STAGE III cells are the most variable in morphology and activity. This stage is characterized by elongation of the cell, increasing flagellar activity, appearance and movement of the ridge, and rotary movements of the entire cell around a posterior point of attachment to the substratum that is finally "broken" when the cells detach.
To view several examples of such cells, click here.

STAGE IV are elongate and show only transient attachment to the substratum. Powered by their very active anterior flagellum, they swim rapidly through the fluid medium.
To view examples of such cells, click here.


* Pagh, K.I. and Adelman, M.R. (1988): Assembly, Disassembly, and Movements of the Microfilament-Rich Ridge During the Amoeboflagellate Transformation in Physarum Polycephalum. Cell Motility and the Cytoskeleton, 11:223-234).

Last modified:Friday, December 19, 2003