Wiellette, E.L., and Sive, H. (2004) Early requirement for fgf8 function during hindbrain pattern formation in zebrafish. Developmental dynamics : an official publication of the American Association of Anatomists. 229(2):393-399.
Fibroblast growth factor (FGF) signaling is required for normal development of the vertebrate brain, including the isthmus and caudal regions of the hindbrain. Recent work in zebrafish has identified a requirement for the combination of fgf3 and fgf8 functions in specification of rhombomeres 5 and 6 (r5, r6), when evaluated at mid- and late somitogenesis stages. However, when examined earlier in development, during early somitogenesis stages, FGF8 alone is required to initiate r5 and r6 development. Both a mutation in fgf8 and injection of fgf8-targeted antisense morpholino-modified oligonucleotides result in suppression of genes normally expressed in r5 and r6 by the one- to two-somite stage. This expression recovers by the six-somite stage, and we propose that this recovery is a response to activation of fgf3 and to delayed accumulation of fgf8. These data demonstrate an early, nonredundant requirement for fgf8 function in hindbrain patterning. Developmental Dynamics 229:393-399, 2004. Copyright 2004 Wiley-Liss, Inc.