Fig. 5. Motifs selected by Xbra (A), VegT (B) and Eomesodermin (C) after five rounds of binding site selection. The consensus sequence is represented at the bottom of each histogram; if a nucleotide is present in greater than 10% of the selected sequences it is defined as being part of the consensus, and in this respect the sites selected by the three proteins differ. However, the core motif selected by all three T box proteins is clearly TCACACCT, and we have been unable to define sequences that are specific for a single member of the family. Note that Xbra shows a preference for a G positioned 5 nucleotides downstream of the core motif; see text for further details.