Structure and activity of Rac1 translocators isolated in this study.

<p><b>(A)</b> Schematic representation of the structure of the Rac1 translocators derived from our cellomic screen. NE, N-terminal extension; CE, C-terminal extension; U, unique region; CC, coil-coiled domain; LisH, Lis1 homology motif; CTLH, C-terminal to LisH; IgG, immunoglobulin-like domain; TM, transmembrane domain; EGF, epidermal growth factor. <b>(B-F)</b> COS1 cells transiently expressing AU5-tagged Rac1 (B), RhoG (C), Cdc42 (D), RhoA (E) and Rac1^T17N (F) either alone (B to F, left panels, labeled as “Mock”) or in combination with the indicated EGFPs (B to F, rest of panels) were fixed, stained with antibodies to AU5, and subjected to confocal microscopy analysis. EGFPs and Rho proteins are shown in green and red color in panels B-F, respectively. Scale bar, 20 μm. <b>(G)</b> Localization of endogenous Rac1 (top panel) and β₁ integrin (second panel from top, negative control) in membrane fractions from COS1 cells transiently transfected with the indicated proteins (top). The expression of endogenous (Rac1) and ectopic EGFPs in aliquots (5% of total lysate) of the extracts subsequently used for the subcellular fractionation studies is shown in the three bottom panels. The antibodies used in the immunoblots are shown on the right. WB, Western blot.