Amphioxus regeneration : evolutionary and biomedical implications

Abstract

Regeneration is a variable trait in chordates, with some species capable of impressive abilities, and others of only wound healing with scarring. Regenerative capacity has been reported in the literature for 5 species from two cephalochordate genera, Branchiostoma and Asymmetron. Its cellular and molecular bases have been studied in some detail in only two species: tail regeneration in the European amphioxus B. lanceolatum; and oral cirrus regeneration in the Asian species B. japonicum. Gene expression analyses of germline formation and posterior elongation in cephalochordate embryos provide some insight into regulation of progenitor and stem cell function. When combined with functional studies of gene function, including overexpression and knockdown, these will open the door to amphioxus as a good model not only for understanding the evolution of regeneration, but also for biomedical purposes.