In cellular society, neurons are the overachievers. When hundreds of billions of them are born in a developing fetus, their work has just begun: they must grow fibers, called axons, that will create the connections of the body’s nervous system. Not only do axons travel remarkable distances from their nuclei (the longest in the human body, belonging to the sciatic nerve, can extend up to a meter long), they must wend their way to the designated spot where these highly specialized cells can close specific circuits dictated by their DNA.
Over the past few decades, scientists’ understanding of how axons navigate to exact targets—what types of signals guide them, and how those signals are received—has grown exponentially, according to Frank Gertler, a faculty member of MIT’s Department of Biology and the Koch Institute for Integrative Cancer Research. His lab is working to solve some of the remaining mysteries about the process, which he likens to a customized GPS system. “We know some of the basic rules and key players, but we know a lot less about how a growing neuron that’s moving through a complex environment coordinates all the information around it and translates that into a precise type of movement,” he says.
Primarily, Gertler and his team study actual neurons from developing mouse brains. But samples of the real thing are delicate, and in short supply. So when they want to run large volumes of experiments, test basic ideas, or drastically manipulate cells (expressing or removing certain genes, for example), they sometimes turn to a close approximation: cells from a brain tumor, like those pictured here.
Tumor cells’ weedlike ability to reproduce and thrive, so threatening inside the body, becomes an asset in the lab. Scientists have capitalized on this for decades: the most widespread of such cell lines, HeLa, dates back to a 1951 case of cervical cancer. Gertler says the usefulness of neuronal tumor cells in research is limited by significant differences from their healthy counterparts. Nevertheless, they are a valuable tool in illuminating fundamental neurobiology.
And in vivid images like this one—currently on display in the Koch Institute Public Galleries, on an enormous canvas visible from the street—Gertler sees another benefit: “It makes you say wow, that’s gorgeous, what is it?” Hanging alongside other winners of the Koch Institute Image Awards, it’s a reminder of the beauty of discovery. “Scientific images contain a lot of information and meaning, but some are also works of art,” the biologist says. “They serve a purpose in sparking imagination and curiosity and interest.”