Fig. 4

Attenuated production of Gdf3 leads to left-right patterning defects.

(A) spaw expression is altered in gdf3 morphants, with most lacking expression in the lateral plate mesoderm (arrow), as shown by RNA in situ hybridization. (B) Immunostaining of aPKC (white) and GFP driven by the sox17 regulatory region (green) in Kupffer’s Vesicle (KV) at 10 ss. The anterior-posterior asymmetry in cell morphology is lost in gdf3 morphants. Cells are outlined by white dashed lines. (C) RNA in situ hybridization reveals dand5 expression is symmetric around KV in gdf3 morphants at 10 ss. (D) Loss of ntla leads to robust spaw expression in both the left and right LPM and a loss of KV and associated gene expression. spaw expression in ntla + gdf3 double morphants is completely lost, supporting the idea that Gdf3 is required for robust Nodal expression given Nodal is unable to activate in the absence of inhibitors. Raw data provided in Figure 4—source data 1–3.