Structure of the lysozyme gene and expression in the oviduct and macrophages.

Lysozyme, a specific differentiation marker for the myeloid lineage of hematopoietic differentiation in mammals (Hansen 1974), is also found in chicken hematopoietic cells (macrophages) (H. Hauser, unpublished work). In the mature hen oviduct lysozyme is produced as one of the major egg white proteins under the control of steroid hormones (Palmiter 1972; Hynes et al. 1979; Schutz et al. 1978). We show that in chicken macrophages and oviduct cells the same mRNAs are transcribed from a single lysozyme gene. In macrophages, however, the lysozyme gene is expressed at a much lower rate and does not seem to be under the control of steroid hormones.