Jun Dimerization Protein 1 (JDP1)

BATF3 is a transcription factor that represses the IL2 promoter by inhibiting AP1 protein complexes .Iacobelli et al. (2000) purified and cloned BATF3, which they called p21(SNFT), from a human T-cell leukemia virus (HTLV)-1-transformed T-cell line based on its ability to bind to HTLV-1 long terminal repeat tax-responsive elements. The 127-amino acid protein is most closely related to rat Jdp1 and contains a basic leucine zipper (bZIP) domain.

Using EMSA analysis, Iacobelli et al. (2000) found that native or recombinant BATF3 interacted with JUN, but not FOS, proteins and protein complexes. Studies of BATF3-transfected and mitogen-activated cells showed that BATF3 specifically repressed IL2 promoter activity. Western blot analysis showed that BATF3 expression was not altered by T-cell stimulation.