Scientists have several ways of peering inside the human
body. The bluntest tool is the X-ray, followed by MRI. These technologies are
highly effective, but they are limited in their application. In order to see the
more minute aspects of an organism, like individual cells, more sophisticated tools
With the advent of fluorescent microscopy, scientists can use
fluorescent dyes and special microscopes to see the inside of cells. However,
these methods require that the cells be removed from the organism, which means
researchers lose the important context of how they behave within a living entity.
But what if cells could be programmed to generate their own
light so that they glow within a living organism? Researchers in the W.M. Keck
Science Department’s Leconte Lab are answering this question using a mixture of
chemistry, protein engineering, and molecular biology.
“For 20 years now, scientists have been utilizing
bioluminescence as a tool for studying how cells function. We are trying to
make new versions of these proteins that will allow not just studying
individual cells, but the interaction of many types of cells in a complex environment,”
explains Associate Professor of Chemistry Aaron Leconte. Supported by the
Research Corporation for Science Advancement Cottrell Scholars program,
Leconte’s project aims to harness and modify the illuminating power of
fireflies to develop more advanced techniques for imaging biological systems.
As a summer research assistant in the Leconte Lab, Edison Reid-McLaughlin ’21 has been gaining invaluable experience in all aspects of this interdisciplinary project.
The first thing Reid-McLaughlin does when he arrives at work
each morning is retrieve bacteria from an incubator and feed them their
breakfast of sugar, so they grow “robust and expressive”—all before breaking
them open to access the enzymes painstakingly encoded into their DNA.
The gene for the enzyme, called Firefly luciferase (F-Luc), is
inserted into mice with tumors so that the cancerous cells generate their own
light. Using sophisticated cameras, scientists may then track the luminescent
cells as they travel within the organism.
“Bioluminescent imaging isn’t really
used in humans yet,” explains Reid-McLaughlin. “But by learning about how cells
behave in mouse models of human diseases, we can learn a lot that could be
applied to humans later.”
For example, by seeing how cancer metastasizes
(that is, how the cells break away from the primary tumor and travel to new
areas of the body) in a mouse model, scientists can form a more nuanced
understanding of how cancer cells behave in general, which gives them a good
starting place for developing drugs or therapies that could be used in human
diagnostics and treatment. “This field of research has immediate implications
for understanding diseases and is an essential step in developing meaningful
treatments,” says Leconte.
Reid-McLaughlin got involved with the Leconte Lab after taking an interdisciplinary introductory chemistry and introductory biology course. The traditional laboratory curriculum was replaced with first-hand research experience, during which Reid-McLaughlin learned sophisticated research techniques and gained an appreciation for open-ended, interdisciplinary lab work. “The first thing I learned was how to handle DNA to figure out how much it weighs,” he recalls, adding that “Scripps’ small size and the personable nature of the professors really cultivates students as future scientists.”
In addition to nurturing the F-luc enzymes in the bacteria, Reid-McLaughlin
assists with computational processing and data analysis. This aspect of the
project is indispensable, as Leconte’s research is at the crux of science and
“One of the challenges in bioluminescent research is that
scientists want the enzyme tailored for different imaging applications, but not
much is known about Firefly luciferase,” explains Leconte. “To learn about it,
scientists have traditionally changed its amino acids one at a time, creating
mutations and carefully measuring the effects, but this is a really slow and
limited approach. Edison’s project for this summer is to initiate new
approaches that can characterize hundreds to thousands of amino acid changes in
a single experiment, rapidly speeding up discovery. I was confident that Edison
had the intelligence, ambition, and perseverance to take on a big, challenging
project like this. He has already pushed the science forward extremely quickly
even in a short amount of time and he’ll be leading this project for years to
But for Reid-McLaughlin, scientific research is only part of
his future plans. He, too, is guided by an inner light: the desire to help
others through education as others have helped him.
“I want to be a scientist, but I also want to be a
professor. Had I not met Professor Leconte and my other instructors at Scripps,
I wouldn’t have even thought about that,” says Reid-McLaughlin, who is already
getting teaching experience by working as a teaching assistant and tutor for a
first-year chemistry course and who is an active member of the Queer Resource
Center’s Alliance Club. “Being at Scripps motivates me to want to do for others
what they have done for me, teaching and encouraging me to pursue my passion.”