Multipotent tail bud cells originated with the chordate common ancestor

In amphioxus embryos, tail bud cells contribute to the neural tube, notochord, and somites, including the post-anal tail region.

• Why it matters: It tests whether the earliest diverging chordate lineage retains ancestral tail bud cell fates, addressing the evolutionary origin of posterior body development.
• What they did: The study traced tail bud cell fate during embryogenesis in the cephalochordate amphioxus, using lineage tracing to track contributions to posterior structures.
• The result: The findings provide direct evidence that ancestral chordates likely had tail bud cells producing both neural and mesodermal derivatives, clarifying chordate posterior development origins.