Cell interactions, signals and transcriptional hierarchy governing placode progenitor induction

Cranial placodes contribute to all sense organs and sensory ganglia in the vertebrate head. Despite their diversity they originate from a common pool of Six1/Eya2+ progenitors. In a molecular screen we identify new factors upstream of the Six1/Eya2 cassette and use these to dissect the transcriptional hierarchy that controls progenitor specification. We find that although two different tissues, the lateral head mesoderm and the prechordal mesendoderm, induce placode progenitors, both initiate a common transcriptional state, but over time gradually impart regional character.

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Hintze M, Prajapati RS, Tambalo M, Christophorou NAD, Anwar M, Grocott T, Streit A