Molecular Reproduction & Development Volume 84, Issue 11, November 2017.

Ctenophores, also known as comb jellies, are non-bilaterian invertebrates and nearly all are self-fertile hermaphrodites. Mnemiopsis leidyi is a particularly useful model for the study of cellular, tissue, and organ patterning in ctenophores due to their extreme transparency, as seen in these adults. The locomotory ctene rows, highlighted by iridescence, overlie the germ line, from which gametes and embryos are readily available in large numbers. In this issue, Davidson et al. characterize transcript expression and timing of the maternal-to-zygotic transition and accompanying zygotic genome activation during early embryogenesis in this ctenophore.