Representational difference analysis using myeloid cells from C/EBPε deletional mice

C/EBPe is a recently cloned member of the C/EBP family of transcriptional factors. Previous studies demonstrated that the expression of this gene is tightly regulated in a tissue specific manner; it is expressed exclusively in myeloid cells. C/EBPe-deficient mice developed normally but failed to generate functional neutrophils and eosinophils, and these mice died of opportunistic infections suggesting that C/EBPe may play a central role in myeloid differentiation. To identify myelomonocytic genes regulated by the C/EBPe gene, we performed representational difference analysis (RDA), a polymerase chain reaction (PCR)-based subtractive hybridization using neutrophils and macrophages from wild-type and C/EBPe knockout mice. We identified a set of differentially expressed genes, including chemokines specific to myelomonocytic cells. Several novel genes were identified that were differentially expressed in normal myelomonocytic cells. Taken together, we have found several genes whose expression might be enhanced by C/EBPe.