Spaceflight Samples Returned on SpaceX-23
Advanced Plant Experiment-08 (APEX-08) Plants
Thirty Kennedy Fixation Tubes (KFTs) containing Arabidopsis thaliana plant tissues returned to Earth aboard SpX-23. The tissues were harvested from seedlings grown on 30 APEX-08 Petri plates in ISS Veggie. APEX-08 launched to ISS on SpaceX-23 to support the Space Biology grant titled “Can Polyamines Mitigate Plant Stress Response under Microgravity Conditions?” (PI Patrick Masson and Co-I Shih-Heng Su, both from the University of Wisconsin, Madison, WI). Six different Arabidopsis thaliana genotypes were grown on five plates each: wild type, three mutants, and two transgenic lines. Astronaut Shane Kimbrough conducted on-orbit operations and grew the plants from September 1 through 10, 2021. The ground control was conducted in a Veggie at KSC in an ISS Environmental Simulator (ISSES) chamber. The plants were grown for nine days, harvested into KFTs, fixed with RNAlater, and placed in MELFI before return to Earth. The tissues (flight and ground) will be shipped to the PI team for post-flight, multi-omics analyses. The plant tissues will be analyzed by the Principal Investigator Dr. Patrick Masson and his team to determine plant stress responses in the microgravity environment. Plant stress poses a significant risk to sustaining plant crops during long duration spaceflight missions to the moon and beyond. APEX-08 will help NASA understand if polyamines can mitigate plant stress response under microgravity in order to identify novel genetic engineering strategies to improve plant adaptation to spaceflight.
Image: Arabidopsis thaliana seedlings following nine days of growth in petri dishes in the VEGGIE growth chamber under temperature, humidity and CO2 conditions mimicking those recorded at the International Space Station.
Veg-03 I and J Crop Specimens
Crops harvested from the Veg-03I and Veg-03J technology demonstration tests on ISS were returned to Earth aboard SpX-23. Veg-03I launched on June 29, 2018 (SpX-15) and included six plant growth pillows: one with Dragoon Lettuce, one with Red Russian Kale, one with Extra Dwarf Pak Choi, one with Wasabi Mustard, and two with Red Romaine Lettuce. The Veg-03I growth test was conducted between January 4 and February 2 in one ISS Veggie and demonstrated the capability of astronauts to autonomously grow, maintain, and harvest space crops. Crew member Michael Hopkins demonstrated the first on-orbit plant transplant during the Veg-03I test. Veg-03J launched on February 2, 2020 (NG-13) and included Red Romaine lettuce seeds in seed film. For Veg-03J, astronauts planted seed film into plant pillows and grew the plants in one ISS Veggie. Veg-03J demonstrated the use of seed film to transport, store, and handle seeds on-orbit, alleviating the need to plant seeds in pillows prior to launch. For Veg-03 I and J, the Kennedy Space Center team plans to conduct microbial and nutritional analyses of the plant specimens returned from ISS.
Image: Astronaut Shane Kimbrough (joined by astronaut Kate Rubins) is photographed during VEG-03 initiation in the Node 2 module.
Microbial Tracking-3 (MT-3) Sampling Kits
Microbial Tracking-3 is a Space Biology investigation cataloging and characterizing potential disease-causing microorganisms aboard the International Space Station (ISS). A new set of microbial sampling kits containing sterile sampling wipes was launched on SpaceX CRS-23 (SpX-23) on August 29. The samples were then returned to the Principal Investigator Dr. Jack Gilbert on September 30. These wipes are used to sample various surfaces on ISS and will be analyzed to identify the types of microbes being found, their interactions, the development of microbial communities, and any microbial effects on human health. Analyzing the ISS samples will help scientists determine the distribution and selection of antimicrobial resistance and virulence genes in microbial and fungal genomes and metagenomes in the ISS environment. These experiments are designed to understand genes and pathways that are under purifying selection in the ISS environment.
Image: NASA astronaut Jack Fischer swabs surfaces in the ISS to collect microbe samples for the Microbial Tracking-3 experiment.
Tardigrade Samples from the Cell Science-04 (CS-04) Experiment
On-orbit operations and near synchronous ground control activities were completed on September 13th. The tardigrades were active on the ISS for 61 days, approximately through four generations. During the 61 days, the team supported the crew on-orbit operations and performed the parallel ground activities. The remaining activities include transferring the Bioculture System and preserved samples to the dragon capsule where they were returned with the SpaceX-23 on September 30. The Principal Investigator Dr. Thomas Boothby is studying tardigrades to characterize their short-term and multigenerational survival by identifying genes required for adaptation and survival in high-stress environments.
Image: A preflight light micrograph of a typical terrestrial tardigrade of the Milnesium genus seen at 40X magnification.
