Title Expression and function of cytokine genes in the early development of fish
Authers Yasutoshi YOSHIURA, Mitsuru OTOTAKE, and Kanako ITO
Keywords cytokine, Macrophage migration inhibitory factor (MIF), early development, zebrafish, morpholino
Citation Bull. Fish. Res. Agen. No.26, 47-52, 2008
Cytokines are a group of proteins that are involved in a variety of immunological and inflammatory reactions. Recently, it has been reported that cytokine genes also play an important role during development in mammals. In fish, however little is known about the role of immunerelated genes during embryogenesis. Here, we report the expression and function of some cytokines during embryonic development in zebrafish. In RT-PCR analysis, the expression of three cytokines (MIF, IL-1 β and TNF- α 2) was detected before the development of the immune system in zebrafish embryos. Moreover, to elucidate the function of MIF during embryonic development in fish, we examined expression patterns and function of the zebrafish MIF gene using antisense morpholinomediated knockdown (morpholino oligonucleotide-MO). In whole-mount in situ hybridization analysis, zebrafish MIF mRNA was detected in developing eyes, tectum, branchial arches, pectoral fin buds, liver and gut. MIF-MO-injected embryos (morphants) displayed malformed eyes, abnormal swelling in the tectum and fourth ventricle region, and undeveloped jaw cartilage and pectoral fins. An increased number of apoptotic cells in the eye and neural tissues were observed in MIF morphants. These results suggest that MIF is essential for normal embryonic development even at the level of teleost.
URI http://www.fra.affrc.go.jp/bulletin/bull/bull26/yoshiura.pdf