FIGURE 4.

The individual domains of G2L3 influence the binding strength to microtubules and actin. To assess the turnover of indicated proteins in NIH3T3 cells, circular areas of 1.5-μm diameter were bleached, and recovery was measured. A, FRAP experiments performed on the actin localizing constructs. Note the slower fluorescence recovery of bleached areas in G2L3-CH (CH)-expressing cells and much faster recovery in G2L3-ΔC-term expressing cells compared with areas in G2L3-expressing cells. B, FRAP experiments performed on MT localizing constructs. Note the similar fluorescence recovery of bleached areas in cells expressing G2L3 and G2L3-ΔCH. Conversely, the fluorescence recovers faster in the bleached areas in G2L3-ΔGAR and G2L3-C-term-expressing cells. Either the prebleach (PRE) or the time in seconds is indicated in the bottom right-hand corner of each image, and the encircled areas indicate the bleach regions. C, the t½ values of recovery of the actin binding constructs are labeled in gray, and the MT-binding constructs are in black. Note that the t½ of recovery of G2L3-CH is almost double that of G2L3, and the t½ of recovery of G2L3-ΔC-term is much faster than G2L3. In accordance with B, the t½ of recovery of G2L3-ΔCH is similar to G2L3, whereas G2L3-ΔGAR and G2L3-C-term have much faster t½ values of recovery. The data represent the results from more than n = 20 bleach regions from n = 10 cells and are representative of three independent experiments. Bars, 5 μm.