Fig. 3. The NES region of hNMD3 directs Ran·GTP-dependent nuclear export of a heterologous protein in Xenopus oocytes. GST fusion proteins containing the wild-type or NESmut version of the C-terminal 79 amino acids (residues 425–503) of hNMD3 were injected into nuclei of control oocytes (top and middle panels) or oocytes pre-injected with RanT24N (bottom panel) to inhibit Ran·GTP-dependent export, and export was monitored with time. One oocyte equivalent of nuclear (N) and cytoplasmic (C) extracts was analyzed by western blotting with anti-GST antibodies. Note the shorter time course for the top (15, 30 and 60 min) versus the middle and bottom (30, 60 and 120 min) panels. GST alone does not exit the nucleus during this time course (Askjaer et al., 1999; unpublished data).