The Blythe lab will identify the factors that initiate the wave of gene activation in the earliest moments of embryonic development. Animals are complex biological machines that build themselves from scratch as cells divide and activate the set of genes that allow them to build all of the tissues of the body. In a fertilized egg, genes are held in an inactive state by the tight packaging of DNA. For embryos to “boot up” their developmental program, there must be factors that can penetrate this locked-down DNA to switch on the appropriate genes. As a postdoctoral fellow, I developed a technique for monitoring, in real time, the dramatic changes that take place in DNA packing in the first minutes of development in fruit fly embryos. Now, combining this approach with techniques in molecular genetics, microscopy, and developmental biology, my lab will identify and map the factors that first access and activate the genes that choreograph early embryonic development—and examine how mutations in these critical components alter the normal patterns of gene expression. Our findings will enrich our understanding of the regulatory networks that guide embryonic development and could lead to new strategies for reprogramming cells for therapeutic applications.