In 2021, a spaceflight experiment was launched to ISS to study how plants respond to microgravity

BRIC-24 is a spaceflight experiment, which was launched to the International Space Station. This experiment was launched on June 3, 2021, on SpaceX's CRS-22 Commercial Resupply mission. When scientists studied plants on Earth, they found that roots and shoots had to respond to gravity by bending them towards or away from the direction of the gravitational vector. Scientists are studying the plants' responses to gravity and how they are related to cellular processes. These researches will help us better know how plants function in space and how space microgravity affects them.

What is the goal of the experiment?

The goals of the experiment BRIC-24 are to determine the molecular processes of gravity perception and gravitropism. Gravitropism is when plants' organs change their orientation according to gravity. The roots can grow downwards, and shoots grow upwards in response to gravity. In microgravity, plants do not have a reason to grow in a particular direction.


When scientists look into gravitropism, they are particularly interested in the interplay between different cellular processes within plant cells. Therefore, the experiment will help us get a better understanding of plants' biological functions and the way they can adapt to changes in their environment caused by gravity.

The vacuole is the largest organelle in plant cells. The researchers are particularly interested in what vacuole-related processes play a role in plants' gravitropic response in microgravity.

Why does the experiment use thale cress?

The experiment uses two Arabidopsis thaliana (thale cress) genotypes. Scientists have chosen thale cress for the experiment because they can easily study its genetics and biological functions. Researchers can grow thale cress in space, and its responses can show scientists how plants behave in microgravity.

The specimens of the plants have fluorescent tags on the vacuole membrane and ER. Scientists can therefore study these structures under microscopes after the plants return to Earth. Scientists can therefore examine the differences between the two genotypes of thale cress when they are exposed to microgravity. The experiment uses fluorescent tags because the plants' genetic information does not provide scientists with all the data they need to study the plants. Examining the fluorescent tags can therefore help scientists find valuable information about the plants.

How are plants prepared and treated aboard the ISS?

The BRIC-24 experiment has a specific protocol for treating the plants.

Launch and temperature: Plants are launched at a low temperature (39 degrees Fahrenheit) and begin germinating after being exposed to the higher temperature of the International Space Station.

Chemical treatment: Scientists will use Wortmannin chemical inhibitor to treat the plants to trigger vacuole fusion. The treatment allows the scientists to examine the effects of vacuole fusions on the plants.

Biological preservation: A few hours after the chemical treatment, the crew will use paraformaldehyde fixative to preserve the plants' cellular structure.

The BRIC-24 experiment uses BRIC-LED canisters to contain the specimens and perform experiments on them. BRIC stands for Biological Research in Canisters. The canister includes Petri Dish Fixation Units (PDFUs), in which the plants grow on agar-solidified growth media. The equipment also has a reservoir, from which the crew can deliver the chemical treatment and fixatives using the manual crew actuator tool. The PDFUs can also be placed in the EXPRESS Rack inside the ISS.

Who leads the BRIC-24 investigation?

The experiment is led by Dr. Marcela Rojas-Pierce, Dr. Mengying Wang, and NASA Project Scientist Ye Zhang. The researchers' work provides insight into understanding plants' response to gravity and adapting to the environment they are in.

How could BRIC-24 findings help agriculture on Earth?

The experiment's findings can be beneficial for biological research on Earth; scientists can use the results of the experiment to find new ways to grow plants. Biological processes, which are involved in plants' gravitropic response, might also be involved in plants' response to other stimuli. Therefore, scientists can use the findings of the experiment to research into new ways of growing plants. However, BRIC-24 is a fundamental research experiment; the findings can only be applied on Earth after more research has been done to verify the findings.

The findings of the experiment can also help scientists develop sustainable ways of growing plants and agricultural crops. Climate change and environmental issues affect plants and agriculture, which can affect food production and resources. A better understanding of plants can help scientists make the best use of our resources when growing plants.

Being able to grow plants is essential for long-duration space missions. It can potentially help us create bioregenerative life-support systems, which can be used to provide food for astronauts and recycle waste.

However, for plants to be useful to astronauts, scientists need to find out how plants respond to gravity. Researchers need to better understand how plants work to ensure that they can grow them in space.