Researchers at Cincinnati Children’s are shedding new light on one of nature’s biggest mysteries – how our bodies attain their forms.

A study published in March 2015 in Nature Communications reports that the size and patterning accuracy of fruit fly embryos depend on the reproductive resources invested by the mother, even before the egg leaves the ovary.

Jun Ma, PhD.

Jun Ma, PhD

“One of the most intriguing questions in animal development is something called scaling, or the proportionality of different body parts,” says Jun Ma, PhD, senior author and a scientist in the Divisions of Biomedical Informatics and Developmental Biology. “Whether you have an elephant or a mouse, their organ and tissue sizes are generally proportional to the overall size of the body. We want to understand how you get this proportionality.”

By studying fruit flies, one of the simplest forms of animal life, Ma and his colleagues are producing mathematical models that will allow them to explore similar questions in more advanced life forms, including humans. Ultimately, such research could help explain the root causes of certain birth defects.

The scientists start in the ovary of the mother fruit fly, where the genetic and biological resources to form the eggs of her future brood are harnessed. Researchers follow development through to the growth of her embryos, and combine mathematical modeling with laboratory testing to get a complete picture. The process requires a large number of experimental measurements and a well-stocked fly room.

In the latest study, funded by the National Institutes of Health and National Science Foundation, Ma and colleagues report developing a mathematical model called TEMS (Tissue Expansion-Modulated Maternal Morphogen Scaling). A morphogen is a protein that instructs genes to make products that control the formation of body parts. The TEMS model lets researchers quantify the mother fly’s biological investment in this process. The larger the investment, the bigger the return in terms of well-proportioned body parts.

The new TEMS model will help Ma and colleagues develop a systems-level understanding of how fruit flies attain their forms - knowledge that ultimately could benefit people of all shapes and sizes.