BRIC-24: An experiment frozen in time and space

A small area of ​​the roots of Arabidopsis thaliana is shown above. This will help scientists study vacuoles, an internal structure of a plant, in the Container-24 Biological Research Experiment, or BRIC-24 for short. This experiment will be launched to the International Space Station aboard SpaceX’s 22nd Commercial Refueling Services mission and will help better understand how plants detect and respond to gravity. A team of researchers, including Dr. Marcela Rojas-Pierce and Dr. Mengeng Wang, worked with a team from NASA’s Kennedy Space Center to prepare BRIC-24 for the flight. Credits: Dr. Minjing Wang / North Carolina State University

Dr. Marcela Rojas-Pierce of North Carolina State University is working with NASA to conduct an experiment called Biological Research in Container-24 (BRIC-24), which focuses on one area, specific plant research: vacuoles.

Vacuoles, which are the largest internal structure of plant cells, are essential for plant growth. They act as a storage area, break down proteins, and help maintain the structural integrity of the plant. BRIC-24 will study whether microgravity affects a plant’s ability to produce and fuse with vacuoles and will help NASA understand why plants grow differently in space than they do on Earth. The experiment will be launched to the International Space Station aboard SpaceX’s 22nd Commercial Refueling Services mission.

“This particular experiment has been combined into a larger project we have in the lab here on Earth, where we are trying to understand how plants respond to gravity,” said Rojas Pearce, principal investigator for BRIC-24. We know the gap is important for this response. We are trying to understand why.”

The experiment consists of cultivating two genotypes of Arabidopsis thalianaa aboard the space station, due to differences in the way their vacuoles are formed. Arabidopsis, a flowering plant, is a model system for studying the processes of growth and development of plants. After these plants germinate, the experiment applies a chemical inhibitor called wortmannin to the plants to induce vacuole fusion in microgravity. This will show whether vacuoles can merge in microgravity, whether the fusion process is accelerated or slowed, and how vacuoles of each type of plant form in space.

Each plant species also bears luminous markers, one of the tools Rojas Pierce and her team developed in the lab. These tags identify proteins in the plant vacuole and the endoplasmic reticulum — another organelle that Rojas Pierce is studying — allowing the team to visualize those organelles in each plant and better understand how they interact with each other.

“We know very little about cell compartments and how cells respond in microgravity; this seemed like a really good opportunity,” Rojas Pierce said. “It’s a very simple visual experiment that I think will teach us a lot about whether there is any change in the rate at which cellular interactions occur. fundamentals in microgravity.

However, what Rojas Pierce believes will be the biggest challenge is what happens next. Teams will attempt to perform a chemical treatment in the plants in real time aboard the space station, preserve that treatment, and send it back to Earth in a preserved state for analysis. Two hours after applying Wortmannin to each type of plant, astronauts aboard the orbiting laboratory treat the plants with a fixative — a solution of paraformaldehyde — to preserve the structure of all the organelles in the cell. Basically, they will freeze those plants in time. It is then stored at 4 °C until it can be returned to Rojas-Pierce and his team for post-flight analysis.

The image above shows the BRIC instrumentation that was used in 2017 as part of an earlier experiment, BRIC-22, on the International Space Station. Similar devices will be used for the BRIC-24 experiment, which is scheduled to arrive in the orbital laboratory on SpaceX’s 22nd cargo resupply mission. Credit: NASA/Peggy Whitson

“This is our first flight experience, so I’m terrified, but at the same time, I’m excited,” she said. “I am looking forward to the experience of doing this challenging experiment and getting good data and learning something about plants, [algo] It cannot be done otherwise.”

Yi Zhang, a NASA project scientist, has been with Rojas-Pierce from the start, primarily providing agency support. While Zhang agrees that the experiment will be challenging, he believes the research team is ready.

“NASA has standardized procedures for conducting experiments like this in space, and the BRIC-Petri dish stabilization unit (or BRIC- Petri dish stabilization unit) that will be used by BRIC-24—the instrumentation developed by the agency—has already been moved several times, Zhang said. That is why We were able to provide the research team with a tremendous amount of technical and logistical support. It really allowed us to make sure that this experiment could be tested and successfully implemented this year.”

Understanding how plants grow in space will allow astronauts to use newly planted crops to support long-term missions to the Moon and Mars. The Dragon spacecraft that will deliver it to BRIC-24, along with several other science investigations that will benefit exploration beyond low Earth orbit, is scheduled to blast off from Kennedy Space Center launch complex 39A on June 3, 2021. About a month later, Dragon will return to Earth , bringing with it BRIC-24 plants saved for analysis along with an additional return fee.

Dr. Marcela Rojas-Pierce’s research is supported by NASA’s Division of Biological and Physical Sciences.

Written by Daniel Simpsrut

NASA Kennedy Space Center

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