FIGURE 3.

Relocalization of FAK-pY576 in response to v-Src-mediated cell transformation is dependent upon annexin 2. R1LA29 cells were partially depleted of annexin 2 as described in the legend to Fig. 5, fixed, and immunostained for annexin 2 (anx 2), FAK-pY576, and F-actin in both the untransformed and transformed states. Following the switch from restrictive to permissive temperature for 1 h, annexin 2-depleted cells (pink arrowheads) remained large and flat with numerous focal adhesions enriched in FAK-pY576. In contrast, annexin 2-positive cells acquired a transformed phenotype in which annexin 2 relocalized to the cell cortex. By 8 h, there was a dramatic increase in the cellular content of FAK-pY576 in annexin 2-positive cells, in which it relocalized to the annexin 2-rich cortex and to the perinuclear annexin 2-rich and actin-rich vesicles (white arrowheads). Relocalization of FAK-pY576 did not occur in annexin 2-depleted cells. Scale bars, 20 μm.