Fig. S3

Involution of the blastoderm is not Mtx2-dependent. Vibratome sections of Tg[sox17:EGFP] embryos (A–C) show that Brachet's cleft can be seen from 60% epiboly onwards by rhodamine–phalloidin staining. Involution, shown in the schematic (top right), still occurs in mtx2 MO injected Tg[sox17:EGFP] embryos (D–G), however, the blastoderm is thicker, presumably because the blastoderm does not migrate as far vegetally. Green arrowheads indicate GFP⁺ cells, white arrowheads indicate YSN, white arrows indicate EVL cells, white asterisk highlights the irregular shape of the blastoderm at the animal pole. DFC = dorsal forerunner cells (not visible in standard controls). Scale bar in A =  150 μm (for A, B, D, E, G). Scale bar in C =  100 μm (for C, F).