Binds the B-response element 5'-CAAGTCCAGGCAAGT-3' of the ENS1/ERNI promoter. May be the major transcription activator thus being essential for its expression. Component of the SSP (stage selector protein) complex, which appears to be a heteromer of TFCP2 and 2 copies of NFE4. Expressed in the epiblast at the pre-primitive streak stage. At the primitive streak stage, expressed in the extending primitive streak and in the prospective neural plate. At stages 7 and 8, expressed in the neural folds, somites and in the regressing primitive streak. At stage 12, ubiquitously expressed in the whole embryo. Belongs to the grh/CP2 family. CP2 subfamily.