Figure 8.

Maximal phagokinesis of 3T3 F442A cells requires SH2B1β. A–F, 3T3 F442A cells expressing GFP or the indicated forms of myc-tagged SH2B1β were plated on colloid gold-covered coverslips, and the areas that became free of colloid gold in 7 h were visualized (outlined). The cells overexpressing GFP or the indicated forms of myc-SH2B1β were stained with α-myc and phalloidin-rhodamine (not shown). Individual transfected cells were located with a FITC filter set (B, D, and F) and then observed by differential interference contrast (A, C, and E). Scale bar, 20 μm. G, A phagokinetic index was calculated as the ratio of the particle-free area to the cross-sectional area of the cells. Bars represent mean ± se. *, P < 0.05 compared with cells expressing GFP. Δ150–200 and Δ615–670 are designated as Δ150 and Δ615, respectively. n = 111, 247, 153, 159, 95, 85, and 63 for cells expressing GFP, WT, Δ150–200, Δ615–670, Δ-Δ, 150–200, and 615–670 of SH2B1β, respectively.