Figure 2
From: Did homeobox gene duplications contribute to the Cambrian explosion?
Expression of ParaHox genes in embryos and larvae of amphioxus Branchiostoma floridae . Whole mount in situ hybridisation used digoxigenin-labelled riboprobes and expression is visualised as blue stain. Each photograph is a lateral view with anterior to the left and dorsal to the top. (A) Gsx gene expression in a neural structure, the cerebral vesicle (arrowhead); ~20 hour embryo. (B) Xlox gene expression in midgut endoderm; ~36 hour larva. (C) and (D) Cdx gene expression in the hindgut and posterior neural tube of ~20 hour embryo and ~30 hour embryo respectively. (E) Cdx gene expression around the anus of 2.5 day larva (arrowhead).