Deep-Sea Diver, Jellyfish Tickler, Radical Empathizer

Seven years ago, while Professor David F. Gruber (GC, Biology / Baruch, Natural Sciences) was photographing corals, he accidentally captured an image of a fluorescent fish — specifically, a glowing green eel that spends most of its life hiding under rocks.

That discovery led to hundreds more. In recent years, Gruber has been the first to document biofluorescence in various species of marine life, including sea turtles, scorpion fish, seahorses, stingrays, and even — in a dark canyon off the California coast, below a stretch of ocean favored by surfers — a neon swell shark.

In addition to discovering these sea creatures and changing our understanding of the underwater world, Gruber is investigating the chemistry behind biofluorescence. “We want to know what it means,” he says. “Why are these animals producing these proteins? And can this chemistry be used for medical and experimental biology tools?” The answer to that, Gruber says, is yes.
Revolutionary Tools in Biomedical Science
Gruber’s interest in biofluorescence dates to his graduate school days, when he co-authored Aglow in the Dark, a book about how a protein from a jellyfish was developed into one of the most revolutionary tools in medical science — one that allows researchers to observe activity within living cells. “We’re visual creatures,” he says. “These tools allow us to see things happening that we’ve never been able to see before.”
Now, along with Professor Jean P. Gaffney (GC/Baruch, Biology/Natural Sciences), he is working to develop a molecule — based on the chemistry of that glowing green eel he discovered — that detects bilirubin, a substance produced by the breakdown of red blood cells. Too much bilirubin in the bloodstream can be harmful, leading to diseases such as jaundice. Gruber and Gaffney’s molecule will light up when the substance is present in the body.
Among his many other projects, Gruber is also studying the proteins that allow bioluminescent ctenophora — gelatinous animals commonly known as comb jellies — to produce light. With colleagues at Yale, Columbia, and the University of California, San Francisco, he hopes to create a molecular tool that will illuminate human neurons as they transmit signals. “We’re working to use bioluminescence to visualize neurons firing, allowing us to better understand and map the brain,” he says. “It’s a potential portal into consciousness.”
Empathy for Marine Life
One theme that unites much of Gruber’s work is a desire to help scientists “explore life delicately,” as he puts it. “I’ve spent a lot of time underwater, scuba diving as well as using submarines to study deep ocean habitats,” he says. “Visiting these places year after year, I realize how fragile these systems are and the impact that we can have on them.”
As part of a team of engineers and marine scientists, Gruber recently developed a 3D printed, robotic claw that can fold itself around a jellyfish, allowing researchers to hold and study these delicate creatures without harming or killing them. The invention was featured in The New York Times
Gruber has also worked with fellow scientists to develop “squishy robot fingers” — hands that can gently interact with deep-sea life ¾ and a camera that lets scientists see what a shark perceives as it moves through the water. He’s also working on a deep-sea genome device, similar to swabs used by forensic crime investigators. “We’re going to tickle the jellyfish and obtain its whole genome,” he says. “And then we’re going to let it go.”
Gruber spends about two months a year in the water, and is already planning a trip for next summer, when he plans to dive under the ice in Greenland. He was once part of a team that did extended-range scuba diving, going almost 450 feet underwater, near the limits of what is safe or possible.
That sense of adventure remains a key driver in all of his work. “The deep ocean is so diverse and so understudied, because it’s been out of reach for most of human history,” he says. Yet this quest for discovery is balanced with a determination to care for life in all its forms. “The deep ocean is filled with creatures that we’ve yet to encounter,” Gruber says. “And when we do, we should encounter them with great respect. And we should be gentle.”

Photo by Elias Carlson

Submitted on: SEP 5, 2018

Category: Biology | Faculty | General GC News