Traveling to nearby extraterrestrial objects having a reduced gravity level (partial gravity) compared to Earth s gravity is becoming a realistic objective for space agencies. The use of plants as part of life support systems will require a better understanding of the interactions among plant growth responses including tropisms under partial gravity conditions. Here we present results from the Seedling Growth space experiments on the ISS to complement the previously released GLDS-251 dataset including seeds of Arabidopsis thaliana wildtype plants. Seeds were germinated and seedlings grew for six days under different gravity levels namely micro-g several intermediate partial-g levels and 1g and were subjected to irradiation with blue light for the last 48 hours. RNA was extracted was obtained for 20 wildtype samples for subsequent RNAseq analysis in GLDS-251 here we add 36 samples from similarly exposed PhyA and PhyB mutants.

Arabidopsis thaliana wild type cell cultures were exposed to a 5-day space flight onboard of Shenzhou 8 to identify microgravity and space effect related gene expression.

Understanding the molecular mechanisms by which plants sense and adapt to changes in the space environment is essential for generating plants that are better adapted to withstand space flight microgravity and other adverse conditions encountered in space. The objective of our spaceflight experiment x93Plant Signaling in Microgravity x94 (carried out on the International Space Station ISS) was to compare transcript profiles of wild type and transgenic InsP 5-ptase plants with compromised InsP3 signaling. The transgenic Arabidopsis plants constitutively express the mammalian type I inositol polyphosphate 5-phosphatase (InsP 5-ptase) an enzyme that specifically hydrolyzes the lipid-derived second messenger inositol 1,4,5-trisphosphate (InsP3). These transgenic plants exhibit normal growth and morphology; however their responses to environmental stimuli including gravity and drought are altered. Seedlings were grown for 5 days under continuous light in experimental containers placed in the European Modular Cultivation system (EMCS) onboard the ISS. The EMCS consists of two rotors within a controlled chamber allowing for a x931g x94 control in space. After sample retrieval from the ISS RNA was isolated from shoot and root tissue and subjected to RNA sequencing. Two-way comparisons of micro g versus x931 x94g have uncovered regulatory mechanisms that are both conserved and altered between the wild type and transgenic seedlings.

This experiment compared the spaceflight transcriptomes of four commonly used natural variants (ecotypes) of Arabidopsis thaliana using RNAseq. In nature Arabidopsis is a native of Europe/Asia/Northwestern Africa and is found across the globe growing in a wide range of environments. The geographical spread of these various populations has led to a slow divergence leading to distinct ecotypes. Understanding the impact of this ecotypic variability is an important factor when using Arabidopsis as a model. Seeds of the ecotypes Col_0 Ler-2 Ws-2 and Cvi-0 were flown to the International Space Station as part of CRS-4 mission in the Biological Research in Canister (BRIC) hardware. The seeds were germinated on orbit grown for 8 days and then fixed in RNAlater and frozen in the MELFI freezer for return to Earth. Once returned RNA was isolated and RNAseq performed to catalog the transcriptional patterns of the plants grown in space. An identical set of samples were grown in parallel on the ground to provide controls to allow assessment of transcriptional changes specifically associated with the spaceflight environment. This data release includes 48 out of 56 sample expression files with the remaining 8 files to be released at a later date.

Arabidopsis thaliana was evaluated for its response to the spaceflight environment in three replicated experiments on the International Space Station. Two approaches were used; GFP reporter genes were used to collect gene expression data in real time within unique GFP imaging hardware and plants were harvested on orbit to RNAlater for subsequent analyses of gene expression with using Affymetrix and SAGE transcriptome analyses. Three tissue types were examined (leaves hypocotyls and roots) and compared to analyses conducted with whole plants. Transcriptome analyses with whole plants suggested that the spaceflight environment had little impact on the transcriptome of arabidopsis however closer examination of selected tissues revealed that there are a number of tissue-specific responses that arabidopsis employs to respond to this novel environment

Gene expression profile of two-week-old etiolated Arabidopsis seedlings under microgravity on board space flight BRIC16 were compared with ground grown control in both wild-type and act2-3 mutant plants.

On Earth plants are constantly exposed to a gravitational field of 1g. Gravity affects a plant in every step of its development. Germinating seedlings orient their radicle and hypocotyl and growing plants position organs at a specific Gravitropic Set-point Angle dictated by the asymmetric distribution of auxin depending on the gravity vector. Hence gravitropism is one of the fundamental growth responses in plants. For any experiment studying the effects of gravity on plants the ultimate control is the microgravity in space. In this study Arabidopsis seeds were flown to the International Space Station and allowed to germinate and grow for 3 days in microgravity. Arabidopsis Wild Type Col-0 seeds were plated onto twenty-two 60mm Petri plates loaded into PDFUs and inserted 4 Biological Research in Canisters (BRICs). Approximately 800 seeds were sterilized plated on each 60mm Petri plates and cold stratified for 16 hours followed by 2 hours of white light treatment. The BRICs were maintained at 4C until spaceflight to ensure seed germination in microgravity. After 3 days of germination and growth the seedlings were fixed by injecting RNAlater into the chamber. They were kept at ambient temperature for 12 hours followed by freezing at -80C. An additional 22 plates were used as ground controls. After the spaceflight tissue from five plates was pooled to make each of three replicates. Both membrane and soluble proteins were extracted from the pooled seedlings. Proteins were trypsin digested labelled with iTRAQ and identified using tandem mass spectrometry.

This experiment compared the spaceflight transcriptomes of four commonly used natural variants (ecotypes) of Arabidopsis thaliana using RNAseq. In nature Arabidopsis is a native of Europe/Asia/Northwestern Africa and is found across the globe growing in a wide range of environments. The geographical spread of these various populations has led to a slow divergence leading to distinct ecotypes. Understanding the impact of this ecotypic variability is an important factor when using Arabidopsis as a model. Seeds of the ecotypes Col_0 Ler-2 Ws-2 and Cvi-0 were flown to the International Space Station as part of CRS-4 mission in the Biological Research in Canister (BRIC) hardware. The seeds were germinated on orbit grown for 8 days and then fixed in RNAlater and frozen in the MELFI freezer for return to Earth. Once returned RNA was isolated and RNAseq performed to catalog the transcriptional patterns of the plants grown in space. An identical set of samples were grown in parallel on the ground to provide controls to allow assessment of transcriptional changes specifically associated with the spaceflight environment. This data release includes 48 out of 56 sample expression files with the remaining 8 files to be released at a later date.

The Cosmic Ray Exposure Sequencing Science (CRESS) payload system is a proof of concept experiment to assess the genomic impact of space radiation on seeds. CRESS was designed as a secondary payload for the December 2016 high-altitude high-latitude and long-duration balloon flight carrying the Boron And Carbon Cosmic Rays in the Upper Stratosphere (BACCUS) experimental hardware. Investigation of the biological effects of Galactic Cosmic Radiation (GCR) particularly those of ions with High-Z and Energy (HZE) is of interest due to the genomic damage this type of radiation inflicts. The biological effects of upper-stratospheric mixed radiation above Antarctica (ANT) were sampled using Arabidopsis thaliana seeds and were compared to those resulting from a controlled simulation of GCR at Brookhaven National Laboratory (BNL) and to laboratory control seed. The payload developed for Antarctica exposure was broadly designed to 1U CubeSat specifications (10cmx10cmx10cm <1.33kg) maintained 1 atm internal pressure and carried an internal cargo of four seed trays (about 580,000 seeds) and twelve CR-39 Solid-State Nuclear Track Detectors (SSNTDs). The irradiated seeds were recovered sterilized and grown on Petri plates for phenotypic screening. BNL and ANT M0 seeds showed significantly reduced germination rates and elevated somatic mutation rates when compared to non-irradiated controls with the BNL mutation rate also being significantly higher than that of ANT. Genomic DNA from mutants of interest was evaluated with whole-genome sequencing using PacBio SMRT technology. Sequence data revealed the presence of an array of genome structural variants in the genomes of M0 and M1 mutant plants.

Life in spaceflight demonstrates remarkable adaptive processes within the specialized environments of space vehicles which are subject to the myriad of attending and unique environmental issues associated with orbital trajectories. To examine the adaptive processes that occur in plants in space leaves and roots from Arabidopsis seedlings that were grown from seed for 12 days on the International Space Station and preserved on orbit in RNAlater were returned to earth and analyzed using iTRAQ broad scale proteomics procedures.