THE C/EBP FAMILY OF TRANSCRIPTION FACTORS

The C/EBP proteins form a family of transcription factors with at least seven members. These proteins consist of three structural components which include a C-terminal leucine-zipper, a basic DNA-binding region and a N-terminal transactivating region. Dimerization through the leucine-zipper leads to formation of homo- and heterodimers which then bind with their two basic regions to often non-symmetric DNA-sequences in the promoter/enhancer regions of a variety of genes. Expression of C/EBP is prominent in adipocytes, hepatocytes and monocytes/macrophages, and here these proteins are involved in tissue-specific gene expression. Target genes for C/EBP include those for acute phase response genes in liver cells and for cytokine genes in monocytes/macrophages. Therefore, intervention at the level of C/EBP transcription factors may prove effective in controlling immune response.