Movie 2.

The beating heart of a Xenopus embryo injected with Co MO. Four-cell-stage embryos were injected in one dorsal blastomere with 7.5 ng Co MO in combination with 50 pg mGFP RNA as a lineage tracer. The embryos were anesthetized with 0.1x MBS (modified Barth's saline) containing 0.01% benzocaine. Beating hearts were recorded at stage 44. A representative embryo is shown from the ventral side. The embryo shows a dynamically beating heart; the blood flow through the ventricle and outflow tract is visible.