Figure 3.

Loss of integrin-mediated adhesion does not hinder the induction of endodermal Labial expression by Dpp secreted from the visceral mesoderm. (A) In wild-type embryos at stage 13, Labial expression (shown in black) is induced in those endodermal cells (arrowhead) in direct contact with visceral mesodermal cells (arrow) that express Decapentaplegic (not shown) under the control of the transcription factor Ultrabithorax (shown in brown). (B) This induction of Labial expression still occurs in the absence of PS integrin-mediated adhesion (lacking the β_PS subunit). Examination of older embryos (stage 16) shows that Labial expression is still maintained in the absence of PS integrins (D), as it is in the wild type (C).