Meeting Abstract

S2-1.5  Wednesday, Jan. 4  The hermaphroditic mangrove killifish as a model for embryological studies KUDOH, Tetsuhiro; Univ. of Exeter, Exeter, UK t.kudoh@exeter.ac.uk

The self-fertilizing hermaphroditic mangrove killifish, Kryptolebias marmoratus, provides us with a very unique genetic model to study processes in embryonic development. To better utilize this species for embryological studies, we have reexamined details of developmental stages from the early cleavage stage to the blastula, gastrula, somitogenesis and organogenesis stages. To clearly observe internal structures during late stages of development, embryos were treated with PTU effectively generating melanocyte-free transparent embryos without causing morphological abnormalities. To visualize the movements of the yolk syncytial layer (YSL), we injected a fluorescent dye, sytox green, in the interphase between blastomeres and yolk and observed the movements of nuclei in the YSL during gastrulation. On the surface of the yolk, a dense network of blood vessels is formed from the mid-somitogenesis stage onwards, which is a very unique and powerful system to observe detailed cell behavior of endothelial cells forming blood vessels. Aiming to obtain gene probes to examine gene expression patterns in the embryos, we sequenced embryonic cDNAs using Solexa/Illumina next generation sequencer. From the sequence analysis, we obtained full-length cDNA sequence for a variety of early marker genes such as sox3, sox2, sox9, otx2, hoxb1b, p63, brachyury, myoD, pax6 and fli1. I aim to discuss the dynamics of these gene expression patterns during the embryonic development of K. marmoratus.