Fig 3. The timing of the significant genes involved in the chicken and zebrafish somitogenesis.

Position of a gene symbol on the plots reflects time of peak timing (angle; clockwise) and the mean expression level (genes with high expression level are closer to the center). The timing is based on 90 and 30 minutes periodicity for the chicken and zebrafish somite cycle respectively. Genes are color-coded according to their known pathway association with green for Notch, brown for Fgf, and purple for Wnt. Genes in blue have never been reported as cyclic but are regulated during chicken and zebrafish somitogenesis. Also, a comparison with Fig 3 of [15] suggests that notable similarities exist between the temporal organization of the pathways involved in the somite clock in chick and mouse, with certain aspects (as the phase of expression of Notch genes) conserved also in the zebrafish.