Visiting Fulbright Scholar Nicolas Carlotto had read many research papers by the University of Delaware’s Jung Youn-Lee during his time studying for his doctorate at the University of Buenos Aires in Argentina.

The agrobiotechnology lab in which Carlotto works and his PhD advisor Ken Kobayshi were also trying their best to perform a Drop-And-See (DANS) technique highlighted in one of her research papers but kept running into roadblocks when they tried to follow the papers’ detailed instructions.

Carlotto’s advisor e-mailed Lee asking for help and her response was that the best way to learn the technique was for her to show one of his students first hand in her lab and so Carlotto applied for a Fulbright Scholarship, in collaboration with Ministry of Education and Sport of Argentina. Once he obtained the scholarship, he made his way from Argentina to Delaware.

He arrived on July 26 for his three-month internship and immediately started working on perfecting the technique of performing a DANS assay.

The DANS assay is a way for researchers to analyze plasmodesmata—or plant communication through cellular channels—permeability in real time.

Lee, professor in the Department of Plant and Soil Sciences in UD’s College of Agriculture and Natural Resources, said that the technique is exactly as it sounds: researchers drop a membrane permeable, non-fluorescent dye onto the upper side of an intact leaf, then cut off the leaf and look through a confocal microscope to see how much the dye, now fluorescent and membrane impermeable, has spread in the lower side of the leaf. This indicates the aperture of the plasmodesmata, which can be imagined as tubes connecting two cells and indicates how the plant is communicating with itself.

“The spread of the dye indicates how the cells’ communication channel, plasmodesmata, are acting,” said Lee. “If the dye doesn’t spread in a big field, it means that plasmodesmata, the channels are mostly closed so that we can tell how plasmodesmata are active in in-tact plants. That gave us a real handle on measuring the plasmodesmata permeability in real time.”

Carlotto said that he is learning from both Lee and Xu Wang, a member of Lee’s lab group and that he was also supported by the Department of Plant and Soil Sciences with funds that let him use the Delaware Biotechnology Institute’s (DBI) Bioimaging Center, an advanced microscopy facility where he has done most of his experiments.

“I learned how to be really consistent with your handling of the experiment,” said Carlotto. “Because perhaps sometimes you don’t focus very well on the health of the plants or on the leaf you want to treat or the time when you set an experiment. You try to do that but sometimes you miss. And coming to a lab where they are really focused on that, it will improve my experience as a scientist.”

Learning from doing has also helped Carlotto instead of simply trying to learn from reading about the experiment in a paper.

“It’s very different when you see how something is done than when you read about it,” said Carlotto who added that he is excited to show members of his lab how to perform the DANS assay back in Argentina as well as other techniques and tools he worked with at DBI.

As for his time at UD, Carlotto said that it has been a great experience.

“I really like the City of Newark,” Carlotto said. “I’m using the Carpenter Sports Building a lot. I used to swim in Argentina when I was younger and it’s been many years but when I came here and found out about the Carpenter Sports building, I go in to swim and use the machines. UD is really great. The campus is nice and you can really feel and experience the university academic ambience of the United States.”