Meeting Abstract

P1-129   -   Growing the toolkit for sea slug science: microinjections in the nudibranch Berghia stephanieae Bock, AK*; Johnston, HJ; Lyons, DC; University of California, San Diego; University of California, San Diego; University of California, San Diego akbock@ucsd.edu

Microinjection is a key technique in developmental biology, as the introduction of fluorescent dyes or nucleic acids to early-stage embryos can be critical to everything from lineage tracing to the generation of transgenic animals. For example, classical “lineage-tracing” experiments--careful reconstructions of cell divisions deduced from fixed specimens--carried out over 100 years ago revealed that animals with divergent body plans like annelids and molluscs share a highly conserved early cleavage pattern called spiral cleavage. Later, modern, intracellular fate mapping techniques emerged and permitted detailed fate maps for a handful of spirally-cleaving animals that were amenable to microinjection. The aeolid nudibranch Berghia stephanieae is an emerging research organism for neurobiology, and thus microinjections in this gastropod mollusc could contribute both to understanding of spiralian early development and to our knowledge of nervous system development. To our knowledge, only one published study has focused on nudibranch cell lineage (on Fiona marina, now F. pinnata, in 1904), and no nudibranch species has been microinjected. Here we present microinjection methods for B. stephanieae using DiI and dextran, as well as fate mapping data at veliger stages for early blastomere lineages. These data lay the framework for future experiments including fate-mapping in the adult, and the generation of transgenic nudibranchs.