| Comments |
P.36 left column bottom paragraph: "Spatial Analysis of Actin Levels in Fibroblasts: To compare the relative levels of G- to F-actin in migrating and non-migrating chick fibroblasts, cells were double stained with fluorescently-labelled DNase I and
phalloidin (Fig. 5a–d) and the ratio level of G- to F-actin obtained by dividing the G-actin image by the F-actin image (Fig. 5e, f). A low G/F ratio is blue, intermediate G/F ratio is green, and a high G/F ratio is red. Migrating and non-migrating cells were stained and photographed under equivalent conditions. The distribution of actin varied as a function of cell migration. In the lamellipodium, the G/F-actin ratio is lower in migrating cells (Fig.5e, white arrow, blue colour) than in non-migrating cells (Fig. 5f, white arrow, green colour). To quantitate this difference, [investigators] calculated the ratio in individual lamellipodia. The average G-/F-actin ratio in the lamellipodium of migrating cells (0.22±0.01, n=121 cells) is 1.7-fold lower than non-migrating cells (0.37±0.01, n=121
cells). In a Student’s 2-tailed t-test, this is highly significant
(P=0.003). In addition, the G/F-actin ratio is significantly reduced in a broad zone immediately behind the lamellipodium, in migrating (Fig. 5e, green, e.g., black arrow) compared with non-migrating cells (Fig. 5f,
red, e.g., black arrow). There was no significant difference in the G/F-actin ratio when averaged over the entire cell body, comparing migrating and non-migrating cells." |