Cyclical generation and degeneration of organs in a colonial urochordate involves crosstalk between old and new: a model for development and regeneration.

  title={Cyclical generation and degeneration of organs in a colonial urochordate involves crosstalk between old and new: a model for development and regeneration.},
  author={Robert J. Lauzon and Katherine J. Ishizuka and Irving L. Weissman},
  journal={Developmental biology},
  volume={249 2},
Botryllus schlosseri is a colonial marine urochordate in which all adult organisms (called zooids) in a colony die synchronously by apoptosis (programmed cell death) in cyclical fashion. During this death phase called takeover, cell corpses within the dying organism are engulfed by circulating phagocytic cells. The "old" zooids and their organs are resorbed within 24-36 h (programmed cell removal). This process coincides temporally with the growth of asexually derived primary buds, that harbor… 

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    Proceedings of the National Academy of Sciences of the United States of America
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