Fig. 7.

Functional roles for LMO4 in neural crest induction. (A) Co-IP assay demonstrating interaction between two LIM domain containing adaptor proteins, LMO4 and Ajuba. (B) Co-IP assay demonstrating that HDAC interacts strongly with Ajuba but not LMO4, indicating that the functions of these two adaptor proteins can be distinguished. Co-expression of LMO4 abrogates the interaction between Ajuba and HDAC, most likely by competing for Ajuba binding. (C) LMO4 is necessary for Slug/Snail-mediated, but not Sox10-mediated, neural crest induction. Whole mount in situ hybridization of embryos co-injected in one cell at the eight-cell stage with LMO4 morpholino and β-gal lineage tracer alone or in the presence of mRNA encoding Slug, Snail or Sox10. Embryos were examined at mid-neurula stages for expression of neural crest marker Sox10. Whereas all three NC regulatory factors can induce ectopic Sox10 expression, only Sox10 can do so in LMO4 depleted cells. These findings point to a more direct the role for LMO4 in the function of Slug and Snail.