4. Pushing with the lamellipodium
Experiments with keratocytes have shown that fragments of lamellipodia can move on their own, in the absence of a cell body (Euteneuer and Schliwa, 1984; Verkhovsky et al., 1998).
The autonomy of the lamellipodium is also illustrated by experiments showing that mechanical manipulation of the keratocyte cell body has no influence on lamellipodium protrusion rate (Fig 4-1,2) (Anderson et al.1996).
Figure 4-1: In Fig. 4-1, a smooth microneedle is used to give the cell a gentle push. The rate of protrusion of the cell front is unaffected.
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Figure 4-2 : In the converse experiment the cell body is restrained: again the rate of protrusion of the cell front is not changed in the short term.
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