A NOVEL HUMAN CCAAT ENHANCER BINDING-PROTEIN GENE, C/EBP-EPSILON, IS EXPRESSED IN CELLS OF LYMPHOID AND MYELOID LINEAGES AND IS LOCALIZED ON CHROMOSOME 14Q11.2 CLOSE TO THE T-CELL RECEPTOR ALPHA/DELTA LOCUS/

Members of the C/EBP family of transcriptional factors have been impli cated in the regulation of genes in a variety of tissues. We report he re the isolation and characterization of the human C/EBP epsilon gene (CEBPE). By using low-stringency hybridization conditions and probes d erived from the C/EBP alpha and C/EBP delta genes, we have isolated ov erlapping genomic clones that cover almost 25 kb of the C/EBP epsilon gene locus and corresponding cDNA clones. DNA sequence analysis reveal s that the gene encodes a protein highly homologous to rat CRP1. The g ene was assigned to chromosome 14q11.2 by fluorescence in situ hybridi zation and was physically Linked to the genetic marker D14S990. Based on linkage data derived from this marker, we positioned the CEBPE gene between the T-cell receptor alpha/delta locus and a cluster of four s erine proteases expressed exclusively in hematopoietic cells. Expressi on of C/EBP epsilon was detected in Jurkat T-cell and in HL 60 promyel ocytic cell lines. From a variety of normal human tissues studied, exp ression of mRNA was monitored only in peripheral blood mononuclear cel ls, tissues involved in the immune system, and ovaries. These data dem onstrate that the C/EBP epsilon gene shows a restricted pattern of exp ression, has an intriguing chromosomal location, and suggest a possibl e role for the regulation of certain genes in cells of myeloid and lym phoid lineages. (C) 1996 Academic Press, Inc.