Kimberly L. Cooper, Ph.D.

Research

In "Origin of Species", Charles Darwin marveled at the many different limb skeletons that are built using "the same bones in the same relative positions". For example, humans have five fingers and toes while horses trot around on what is essentially a single, middle finger. My research explores the molecular mechanisms that have sculpted the shape of animal limbs throughout evolution to give rise to vastly different forms and functions. To probe the developmental program that nature uses to tinker with these structures, I have set up a colony of three-toed jerboas-- rodent relatives of the mouse that hop around bipedally on elongated hind limbs. In my postdoctoral studies, I discovered that the activity of genes that promote cell death remove two of the jerboas' five toes during development. I will take advantage of genetic and genomic approaches to transfer fragments of jerboa DNA that control these genes into mice in an attempt to understand the evolution of gene regulatory control. I will then use biochemical and computational methods to identify the precise regulatory mechanisms that sculpted this change. These results will shed light on the evolution of the vertebrate limb and could be relevant for human birth defects and other disorders in which musculoskeletal development is disrupted.