ABSTRACT
The embryo of the ascidian Ciona intestinalis displays striking anatomical simplicity, with an invariant cleavage pattern during development. It has a monoploid genome like the model organisms Drosophila melanogaster and Caenorhabditis elegans, whereas vertebrates generally exhibit tetraploidy. In this study, I took advantage of these characteristics to investigate the development of the organism as one reverse-engineers an industrial product. First, the spatial expression of 211 genes was digitalized. Some genes showed variable expression patterns, which might reflect multiple snapshots of a single temporally dynamic expression at different times. Several developmental territories of the embryo were considered to be very similar to each other; however, this digitalization of gene expression patterns showed that differences occurred between individual blastomeres even within a single developmental territory. Furthermore, Ciona Brachyury (Ci-Bra) was expressed in those blastomeres in which both Fox (forkhead-box) A-a and Zic (zinc-finger) L were expressed, these proteins being upstream regulators of Ci-Bra. The approach described enables the developmental program to be studied in silico.
SUMMARY STATEMENT A detailed expansion of our knowledge on an animal developmental program by using already published gene expression data with the aid of computers
Footnotes
E-mail: yharada{at}bio.nagoya-u.ac.jp Phone: +81-52-789-5514 Fax: +81-52-789-4204