Figure 5.

Import of anti-coilin antibody C236 into coiled bodies at 4 and 18°C. (A) C236 was injected into the cytoplasm of Xenopus oocytes. After 18 h of incubation in CHX-containing OR2, GV spreads were stained with Cy3-conjugated goat anti-rabbit antibody. The total fluorescence of individual coiled bodies was measured with a charge-coupled device (CCD) camera and plotted against coiled body volume. The linear relationship indicates that the amount of imported antibody is directly proportional to volume. At 4°C, import of C236 into coiled bodies was noticeably reduced, suggesting that shuttling is an energy-dependent process. (B) The slopes of the lines in A represent the concentration of C236 in coiled bodies (fluorescence intensity per unit volume). The concentration is four times higher at 18 than at 4°C.