L-R: Sara Khalil ’15, Savvas Constantinou ’12, Professor Terri Williams, and William Blaine ’15. Photo by John Atashian

Research into the process of segmentation during the embryonic development of arthropods by Trinity College Research Associate Professor Terri Williams, working in collaboration with colleagues at the University of Arizona, has been published in Nature Communications, the prestigious online journal. Titled “Changing cell behaviors during beetle embryogenesis correlates with slowing of segmentation,” the article was published April 10.

Arthropods are a large and diverse group of animals whose bodies consist mainly of repeated segments. With her students at Trinity, Williams explores the embryonic development of segments in order to better understand how development is modified during the course of evolution in the natural world.

Williams said that the collaborative research team found two surprising results that point to a very dynamic model of cell behavior during beetle embryogenesis. “First, beetles don’t add their segments in the regular, clocklike fashion that would be predicted from segmentation clocks in other animals,” she said. “Instead, they slow down in the middle of segmentation, then add segments quite rapidly.”

“Secondly, we labeled cells in the posterior of the embryo in a region called the ‘growth zone,’” said Williams. “What we found was the first direct demonstration that cells in the posterior of an insect embryo do not undergo a lot of cell division, but move quite extensively to elongate the embryo during segmentation.”

“Interestingly, cells marked in the anterior embryo undergo much less cell movement and this switch in cell behavior of the anterior versus posterior clones occurs right after the slow-down in segmentation, suggesting that the two processes might be causally related,” she said.

Joining Williams as Trinity co-authors of the research article were Trinity senior biology major William Blaine ’15; Austin Tewksbury, a 2013 Trinity graduate; and Savvas Constantinou, a 2012 Trinity alumnus and Biology Department research technician.

Williams said that one of the most satisfying parts of her work is being able to create opportunities for students to be connected in collaborative working relationships with colleagues at other institutions of higher education. William Blaine ’15, who has focused on the computer modeling aspects of Williams’s research lab, has worked closely with a research team member at the University of Arizona, regularly comparing notes through online meetings. Sara Khalil ’15, who is currently working on her senior thesis with Williams, spent the summer of her sophomore year working on the arthropod research at the University of Arizona.

​“Throughout the academic year, we have various mechanisms here on campus for students to present research,” said Williams. “I also work with students through Trinity’s Summer Science Research Program. I love that students can have that broader research experience here at a small liberal arts college like Trinity,” said Williams. “It’s like a mini graduate school experience.”

The research on segmentation in arthropods discussed in the Nature Communications article was made possible through a $494,000 National Science Foundation (NSF) grant that Williams was awarded in 2010. More recently, she was awarded a three-year, $488,000 NSF grant to continue her research. This latest grant includes collaboration again with the University of Arizona’s Lisa Nagy, professor, molecular and cellular biology, as well as with Ariel Chipman, associate professor at the Hebrew University of Jerusalem. Earlier this semester, Chipman visited Trinity to give a Biology Department talk.

This second NSF grant also includes collaborative work between Trinity’s Biology Department and its Computer Science Department, noted Williams. Trinity Professor of Computer Science Ralph Morelli is a key contributor working with the research team, she said.

A member of the Trinity College faculty since 2010, Williams holds a B.S. from Duke University and a Ph.D. from the University of Washington.

Nature Communications is an online journal publishing high-quality research from all areas of the natural sciences. Papers published by the journal represent important advances of significance to specialists within each field.