Figure 6.

HoxB9 expression patterns. (A) Evaluation of HoxB9 gene expression by in situ hybridization. Black arrowheads highlight asymmetrical expression around the Henson's node. (B) Representation of the percentage of embryos that display HoxB9 expression. Numbers indicate the experimental N. Red boxes highlight the developmental stage where over 50% of the tested embryos present HoxB9 staining. (C) In situ hybridization images obtained with increasing times of staining reaction, evidencing graded HoxB9 expression. (D) Transverse section analysis of HoxB9 expression patterns in different developmental stages. hf – head fold; hn – Hensen's node; ps – primitive streak; ect – ectoderm; end – endoderm; epi – epiblast; hyp – hypoblast; nt – neural tube; s – somite; psm – presomitic mesoderm; fg – foregut; nc – notochord.