New placode progenitor
transcripts. (A,B) Six1 (A) and Eya2 (B) expression at HH7+/8−. (C) aPPR and pPPR from HH6 (Lleras-Forero et al., 2013) and mesoderm-induced (MIE) and non-induced ectoderm (NIE) were analysed by microarray. (D) Cluster C2 transcripts are excluded from the PPR, such as Cux1 (D′). (E) Cluster C4 includes aPPR- and pPPR-enriched factors, such as Trim24 (E′). (F) Cluster C5 includes aPPR factors, such as Nfkb1 (F′). (G) Cluster C6 includes pPPR factors, such as Gbx2 (G′). Bars in D′-G′ indicate level of sections shown beneath.