Stereotyped distribution of midbody remnants in early C. elegans embryos requires cell death genes and is dispensable for development

Dear Editor, The midbody is a structure formed within the inter- cellular bridge towards the end of cytokinesis [ 1 ]. Microtubules within this bridge are then severed on one side of the midbody during abscission, thus generating a midbody remnant in one of the resulting daughter cells. Midbody remnants persist long after cell division and ac- cumulate preferentially in stem cells, induced pluripotent stem （iPS） cells, and cancer stem cells [2-4]. Upon in- duction of differentiation, midbody remnants are degrad- ed by autophagy or released into the extracellular milieu in some tissue culture cells, and it has been proposed that such removal is critical for enabling a differentiation pro- gram [2-4]. However, the fate of midbody remnants in a developing organism remains elusive, and whether their presence plays a role in cell fate determination in vivo is not known.