California redwoods first inspired Gabriela Amodeo’s interest in plant science. The sheer size of the trees sparked her curiosity. “Since childhood,” she explains, “I was impressed with a photograph of the tallest trees in nature, and I was puzzled with the idea of how nature could deal with altitude and water transport to and from the tiny leaves on top of these trees: water, gravity, fluids, tension…inadvertently, I was looking at nature with biophysical eyes!”
Amodeo’s parents were very encouraging of her curiosity and academic interests, and always had books available for her. Thus, she became a voracious reader. She says, “Reading was like breathing. I grew up with Encyclopedia Britannica, among many other books. I was taught to look at the books to find answers.” Given her interest in botanical questions, Amodeo decided to study biology. When she took her first plant physiology class, she knew that she had found the right course of study for her.
Amodeo completed her bachelor’s degree in biology at the National University of the South in Bahia Blanca, Argentina, the city where she grew up. She continued at the university for her graduate program, studying ion channels in plant cells. “The first time I was invited to a laboratory to watch an experiment in electrophysiology, "Amodeo remembers, “ I saw an oscilloscope trace signal. I was told that the signal was produced by a live ion channel opening and closing at regular intervals: ions moving through a cell membrane!” She began using electrophysiology techniques, specifically patch clamping isolated vacuoles, isolated from an algae (Chara corallina), and later in her work continued on ion channels in onion (Allium cepa) guard cells. Early on, Amodeo had great difficulty with this technique. She explains, “Patch clamping plant cells is kind of tricky—not as easy as with animal cells. For some reason it is difficult to obtain good seals. I thought I would never see a nice and clean result out of my setup.” After this difficult start, she was able to move forward with her thesis work.
"I was impressed with a photograph of the tallest trees in nature, and I was puzzled with the idea of how nature could deal with altitude and water transport to and from the tiny leaves."
-Amodeo
It was during her time in graduate school that Amodeo met Ariel Escobar at a biophysics meeting in Tigre, Argentina, and her research impressed him even then. “She was a real pioneer,” he remembers, “I think she was the first person to work in algae channels in Latin America.” In the early 1990s, Escobar worked in the Department of Physiology at the University of California, Los Angeles, while Amodeo was employed in its Department of Biology. The two collaborated on a project assessing the function of guard cells, which allow the exchange of gases in a leaf. These cells swallow when illuminated with blue light; the increase in cell volume is mediated by an influx of water and potassium ions. “These are some of the very few cells where potassium can influx the cell through ionic channels because the membrane potential is more negative than the potassium equilibrium potential,” Escobar explains. “Finally, water and potassium are accumulated inside an intracellular organelle, the tonoplast. Thus, we studied the potassium channels in the tonoplast membranes that allow potassium permeation.” The project went extremely well, resulting in a paper published in Plant Physiology.
Amodeo continued to work on ion channels throughout her postdoc years, and then transitioned to plant-water relation, specifically plant aquaporins. “I wanted to continue my work in ion channels,” she explains, “but Mario Parisi’s group specializing in water transfers in epithelial cells seduced me into exploring the recently discovered water channels, not only in their systems but also in plant cells… [plant aquaporins] were discovered in the 1990s and nobody knew at that moment how wide their distribution was through all the kingdoms and their relevance in the plant field.”
Currently, Amodeo is a professor in the Department of Biodiversity and Experimental Biology at the University of Buenos Aires. Her lab continues to focus on water relations in plants, using biophysical and physiological approaches. “Our aim is to understand regulatory mechanisms that enhance water permeability. We have evidence that heterotetramerization and gating can jointly affect the water transport capacity of the membrane. We would like to integrate this information with plant-water relations, because there are still many open questions.”
"You always think and fear that you are facing an experimental bottleneck, but, particularly in biophysics, there is always the possibility of employing resourceful newly developed techniques."
-Amodeo
The excitement of being a biophysicist, for Amodeo is in the breadth of techniques consistently being developed. She says, “You always think and fear that you are facing an experimental bottleneck, but, particularly in biophysics, there is always the possibility of employing resourceful newly developed techniques to proceed on the quest for knowledge.” The exposure to new techniques and varied approaches typical of the Biophysical Society Annual Meeting has influenced Amodeo’s decision to attend. She adds, “The (Annual) Meetings provide a very broad perspective of different scientific approaches not only by demonstration of new techniques but also allowing interaction between people from many different fields. They give you a perspective you never thought about. It is very important for young people to have this unique opportunity to share and learn.” She has encouraged the young people she works with to apply for the Society’s travel awards so that they might benefit from that same broadened perspective.
When she is not in the lab, Amodeo enjoys photography and cooking. Escobar recalls a particularly exciting picnic during their days at UCLA, “Gabriela is a great cook. I remember trying to prepare a barbeque at Joshua Tree National Park during summer, for Eduardo Perozo. The meat —and us—were cooking with no fire due to the extreme heat.”