For a geneticist like Associate Professor of Biology David Angelini, soapberry bugs offer a compelling window on evolution, yielding insights that connect to human health. Depending on the environment in which it matures, a bug can either develop long wings and fly, or remain earthbound and reproduce more. Understanding the genetic mechanism behind this adaptive feat could help shed light on processes that relate to a variety of medical conditions, from diabetes to cancer.
This data visualization wall, inside the Paul J. Schupf Scientific Computing Center, is one of the newest academic innovations at Colby that is utilized by students as the College integrates data science throughout its curriculum, thanks to a gift from Trustee Rick McVey P’12, ’16.
Angelini’s lab at Colby is crawling with hundreds of his red-bodied subjects. Working with students, he has sequenced the insect’s genome, thanks in part to an award from the National Science Foundation. Now he is taking the research further with funding from the McVey Data Science Initiative.
“Two years ago, getting the full genome sequence for this insect seemed like it was technically insurmountable,” Angelini said. Technological advances have made the sequencing possible, he added, but what emerged was akin to a static picture. Funding from the data initiative allows a closer look at the expression of all of those genes—the DNA in action.
When he was an undergraduate at St. Mary’s College in Maryland, Angelini’s primary interest was history. Being a teaching assistant for an introductory biology class made him realize he liked working with students in the lab, and he went on as a postgrad to focus on molecular biology, earning a Ph.D. from Indiana University.
In his mind, biology isn’t so far off from history: both disciplines are centered on the stories that got us to today.
“A lot of times in biology … we are teasing out the stories of animals, plants—these organisms that have amazing experiences,” he said. “If you dig, you can figure out what kinds of experiences they’ve had through their evolution. It’s really satisfying to work that out.”
The soapberry bug’s story is intertwined with that of the Chinese goldenrain, a fluffy-looking tree with yellow flowers that became a popular ornamental planting in southeastern U.S. suburbs in the 1950s. Soapberry bugs love to feed on goldenrains, and as the trees spread, so did the bugs.
“Two years ago, getting the full genome sequence for this insect seemed like it was technically insurmountable,” Associate Professor of Biology David Angelini said. Technological advances have made the sequencing possible, he added, but what emerged was akin to a static picture. Funding from the McVey Data Science Initiative allows a closer look at the expression of all of those genes—the DNA in action.
Angelini first began working with soapberry bugs while teaching at American University, but it wasn’t until he got to Colby in 2012, he said, that the genetics research really took off. In the intervening years, he has identified certain pathways that are important to the bug’s development. Food availability, for example, helps determine the wing size; if there’s less food around, the bugs will evolve so they can fly to look for more. More food, on the other hand, translates to shorter wings and more offspring.
Part of the task, then, is to explore how environmental changes beget genetic ones. He has observed that insulin exposure, for example, plays an important role in signaling to the bugs what traits they should develop. He and his students are also analyzing how the expression of certain genes varies with environment.
“Many of those [genes] are involved in cancer processes in humans,” he said. “It’s not surprising, because what we’re talking about here is the control of growth.”
Only a centimeter long, the soapberry bug can churn out a massive amount of data. Its genome contains 2.2 billion nucleotide pairs, the building blocks of DNA. (Humans have about 3 billion.) That translates to about 20,000 genes that can be studied, and Angelini’s lab is looking at the expression of those genes across some 300 individual insects, all raised under different conditions.
Colby’s computational biology major is training a cohort of students to work with data in new ways, which has become so essential to modern science.
This is where computational biology becomes an important tool. “You can’t do this one at a time,” Angelini said. “You have to have software and algorithms to handle all this data, to organize it, to draw conclusions out of it.”
Colby’s new computational biology major is training a whole cohort of students to work with this type of data, which has become so essential to modern science. Vaccine development for the novel coronavirus, for example, has been accelerated by the fact that the virus’s genetic sequence was identified and released publicly.
It’s not just soapberry bugs that respond biologically to their surroundings, Angelini points out. Every organism does it. The bugs just happen to display an obvious giveaway: their wing size. “People should not lose sight of the fact that environmental factors can also be really important, not just for the phenotype of a bug, but for health outcomes for patients,” Angelini said.
Students in Angelini’s lab can take the opportunity to delve into the insect’s genome in any number of different directions. (See below.) He doesn’t lack interested apprentices: though the pandemic has reduced the lab’s occupancy somewhat, he’s advising more students than ever.
As analysis of the soapberry bug’s genome progresses, there’s an opportunity for students to dive deeper on any given gene, exploring its role, Angelini said. “That’ll keep us busy for a long time.”