Fig. S4

Effect of SU5402 treatment on gastrulation movement and the expression of PSM markers. (A) We examined whether the differentiation and maintenance of the PSM are affected by SU5402 treatment. The presumptive PSM was monitored by the expression of tbx24 and papc. tbx24 is expressed in the anterior two-thirds of the (presumptive) PSM and papc is known to be a paraxial mesoderm marker. Their expression domains were found to posteriorly regress in the SU5402-treated embryos, indicating that SU5402 treatment affects the size of the presumptive PSM. This is not the result of compromised cellular movement because the cellular movement was not affected by SU5402 treatment (see Fig. 3B and Fig. S5B), but possibly by differentiation defects. As described in the main text, we think that the change in her1 spatial pattern in SU5402-treated embryos is not merely a result of decreased size of the presumptive PSM. (B) The anterior limit of the gastrulating mesoderm (yellow arrowheads) reaches the head region normally in the SU5402-treated embryo. This indicates that the gastrulation movement is not substantially affected by SU5402 treatment.