This application is for a research training grant to allow the applicant to gain research experience in protein chemistry, immunochemistry and cell biology and at the same time extend his previous training in recombinant DNA methods, by conducting research on the control of gene expression during granulopoiesis. The research program is divided into two phases. In Phase I the applicant intends to carry out research in Dr. Frank Ruddle's laboratory on the regulation of the transferrin receptor gene in a promyelocytic leukemia cell line. A DNA-protein blotting procedure recently developed in Dr. Ruddle's laboratory will be utilized to characterize proteins that regulate transcription of the transferrin receptor gene. Phase II will be spent in the laboratory of Dr. Edward Benz and will consist of studies on the regulation of genes other than the transferrin receptor gene during the maturation phase of granulopoiesis as exemplified by the induction of a promyelocytic leukemia cell line to terminal maturation. Proteins regulating the transcription of these genes will be characterized. These studies are expected to give the applicant broad training in all areas of molecular biology and at the same time produce illuminating information on the regulation of granulopoiesis.