GENE FOR A TISSUE-SPECIFIC TRANSCRIPTIONAL ACTIVATOR (EBF OR OLF-1), EXPRESSED IN EARLY B-LYMPHOCYTES, ADIPOCYTES, AND OLFACTORY NEURONS, IS LOCATED ON HUMAN CHROMOSOME-5, BAND-Q34, AND PROXIMAL MOUSE CHROMOSOME-11

Murine B lymphocytes, adipocytes, and olfactory neurons contain a DNA- binding protein that participates in the regulation of genes encoding tissue-specific components of signal transduction. Purification and cl oning of this protein, termed early B-cell factor (EBF), from murine B lymphocytes and independent cloning of a protein, termed Olf-1, from olfactory neuronal cells revealed virtual complete amino acid sequence identity between these proteins. As a first step towards identifying a human genetic disorder or mouse mutation for which EBF could be a ca ndidate gene, we have chromosomally mapped the corresponding locus in both species. By Southern hybridization analyses of somatic cell hybri d panels with murine cDNA probe, fluorescence chromosomal in situ hybr idization (FISH) of human genomic clones, and analysis of recombinant inbred mouse strains, we have found single sites for EBF homologous se quences on human Chromosome (Chr) 5, band q34, and on proximal mouse C hr 11, in an evolutionarily conserved region.