Originally isolated from osteoblastic cells, the TGF-beta-inducible early gene-1 (TIEG1) is a Krupel-like zinc finger transcription factor-encoding gene which regulates cellular growth and differentiation. TIEG1 is regulated as an early response gene by TGF(beta)1. It is expressed in both acinar and ductular epithelial cells from exocrine pancreas and may serve as an early response gene in pancreatic cell lines. Further, overexpression of TIEG1 in TGF(beta)-sensitive epithelial cells induces apoptosis. TIEG1 and EGR-(alpha) are expressedfrom alternate promoters of the same gene. TIEG1 and EGR-(alpha) are both highly expressed in human fetal osteoblast cells. TIEG1 is additionally expressed at high levels in PBLs, spleen and colon, and at lower levels in thymus, small intestine, ovary, prostate and skeletal muscle. The nuclear TIEG2 protein, which shares significant homology with TIEG1, was originally isolated from globin-expressing human fetal eryth-roid cells. TIEG2 is also expressed in fetal liver. Overexpression of TIEG2 in cultured epithelial cells inhibits cellular proliferation; TIEG2 expression is upregulated by TGF(beta)1 and serum deprivation.