Figure 4.

Injection of RNAs encoding either N-terminal Cdc20 or Cdh1 block the early Xenopus embryonic divisions. Embryos at the 2-cell stage were injected in one cell with RNAs (500 pg) encoding either (A) MTCdc20, (B) MTCdc20N120, (C) MTCdh1, (D) MTCdh1N125, or (E) H₂0 and fixed at stage 6.5. Injection of MTCdh1N125 RNA results in cells that have enhanced nuclear staining. Embryos injected with MTCdhN125 RNAs (D) were fixed at stage 6.5 and stained with propidium iodide. Uninjected side (F) and injected side (G) of the same embryo shown at the same magnification. The cells on the injected side have much larger, more intensely staining nuclei (G) than the cells on the uninjected side (F).