Fig. 4. Rh50 acidic clusters are sufficient for CV targeting. Dictyostelium cells expressing the indicated construct were double-labeled with the anti-CsA antibody (41-71-21) and the polyclonal antibody to calmodulin and analyzed by confocal microscopy. Although a domain containing only the diaromatic signal (pFL760) did not allow the transport of the CsA-Rh50 mutant to the CV, domains containing one (constructs pFL759 and pFL786) or two acidic signals (pFL761) were sufficient for targeting to the CV. Mutation of the acidic residues to alanine (pFL778) prevents the expression of CsA-Rh50 to the CV. Bar, 10 µm.