We compared the transcriptomes of Amphioxus (Branchiostoma lanceolatum) control and SU5402 treated embryos to define putative FGF signalling pathway target genes during somitogenesis. Embryos were treated with 50µM of SU5402 from 5.5hpf to 8.5hpf, 11.5hpf, and 14.5hpf or from 15hpf to 18hpf, 21hpf, 24hpf. Total RNA was extracted from control and treated embryos. Overall design: Comparison of transcriptomes between control and SU5402 treated emrbyos at three time points and for treatment at two developmental stages.