In 'higher animals' these factors are involved in specification and patterning of the endodermal derivatives (such as gut), and we have recently demonstrated that in sponges they are expressed during formation and maintenance of the choanoderm (the innermost feeding layer which we hypothesise is homologous to the gut). Project open to PhD students and Postdocs.
Figure legend: Expression patterns of the Calcisponge Sycon ciliatum developmental transcription factors with conserved functions in animal endomesoderm. a, Brachyury is expressed in micromeres of preinversion stage embryos and, weaker, in choanocytes; b, GATA is expressed in anterior-most micromeres of postinversion stage embryos and in accessory cells (derived from choanocytes); c, Cdx is expressed in the inner cell mass (containing micromeres differentiating into choanocytes) of a metamorphosing postlarva; d, GATA is uniformly expressed in choanocytes of a young syconoid sponge.
From: Fortunato, S. et al. (2015) Comparative analyses of developmental transcription factor repertoires in sponges reveal unexpected complexity of the earliest animals. Marine Genomics. doi:10.1016/j.margen.2015.07.008