Fig. 2. Xbra, VegT and Eomesodermin can function as transcriptional activators. Expression constructs encoding Xbra, VegT or Eomesodermin, or truncated versions of the proteins (see Materials and Methods), were transfected into 3T3 cells along with a reporter plasmid in which the sequence TTTCACACCT is placed upstream of a minimal promoter (below). All three T box proteins activated transcription, and activation was reduced in the truncated versions.