Notch inhibition study on developing eyes in the squid Doryteuthis pealeii

Neurogenesis, the regulation of cellular proliferation and differentiation in the developing nervous system, is the process that underlies the diversity of size and cell type found in animal nervous systems. Coleoid cephalopods, including squid, cuttlefish and octopus, have the largest nervous system of any invertebrate and convergently-evolved camera-type eyes, making them a compelling comparative system to vertebrates. To better understand how changes in neurogenesis may contribute to the evolution of large and complex nervous systems, we sought to understand neurodifferentiation in the cephalopod Doryteuthis pealeii. We were interested in understanding the role of Notch signaling in regulating cell fate and proliferation in the cephalopod retina. To assess the role of Notch signaling we again used the gamma secretase inhibitor DAPT to inhibit active signaling. Embryos were treated with DAPT or DMSO starting at Arnold stage 23 for 24 hours. Eyes were dissected and pooled. RNA was extracted from three experimental and control samples and sequenced.