Injection of anti-XCdc14α/β antibodies into Xenopus embryos blocks cell division. One cell of 2-cell Xenopus embryos was injected with 10 nL of XB Buffer, purified rabbit IgG (final concentration ~1 μM), anti-XCdc14α/β antibodies (~200 nM final concentration), anti-XCdc14α/β antibodies pre-incubated with the immunizing antigen ("Blocked"), or GST-hCdc14A (1 μM). Left: examples of embryos injected with α-XCdc14α/β antibodies (top) or pre-blocked α-XCdc14α/β antibodies. Right: summary of two independent experiments. Embryos were analyzed at the 32-cell stage, and only embryos with an obvious large blastomere phenotype were considered abnormal.