BIOCHEMISTRY

Defining the interaction of Zelda with chromatin

One question that fascinates many scientists is — how are so many different cell types (from those in our eyes to our intestines to our toes) all encoded by the same DNA? It’s certainly a question that fascinates Katharine Schulz and the rest of the lab of IPiB-faculty member Melissa Harrison. They study how proteins, called transcription factors, drive cell-fate decisions by determining which genes to turn on and when. One of these transcription factors is called Zelda and was the focus of Katharine’s Ph.D. Working in fruit fly embryos, she found that Zelda is required for the process of opening up DNA in cells to turn on the expression of many genes and kick-start development. Further, she found Zelda opens chromatin by interacting directly with DNA even when it is wrapped by proteins to form nucleosomes. Her work to understand how cell fate gets directed can help others reprogram cells for specific uses, like therapeutics.