Shared Metabolic Remodeling Processes Characterize the Transcriptome of Arabidopsis thaliana within Various Suborbital Flight Environments

Abstract

The increasing availability of flights on suborbital rockets creates new avenues for the study of spaceflight effects on biological systems, particularly of the transitions between hypergravity and microgravity. This paper presents an initial comparison of the responses of Arabidopsis thaliana to suborbital and atmospheric parabolic flights as an important step toward characterizing these emerging suborbital platforms and their effects on biology. Transcriptomic profiling of the response of the Arabidopsis ecotype Wassilewskija (WS) to the aggregate suborbital spaceflight experiences in Blue Origin New Shepard and Virgin Galactic SpaceShipTwo revealed that the transcriptomic load induced by flight differed between the two flights, yet was biologically related to traditional parabolic flight responses. The sku5 skewing mutant and 14-3-3κ:GFP regulatory protein overexpression lines, flown in the Blue Origin and parabolic flights, respectively, each showed altered intra-platform responses compared to WS. An additional parabolic flight using the F-104 Starfighter showed that the response of 14-3-3κ:GFP to flight was modulated in a similar manner to the WS line. Despite the differing genotypes, experimental workflows, flight profiles, and platforms, differential gene expression linked to remodeling of central metabolic processes was commonly observed in the flight responses. However, the timing and directionality of differentially expressed genes involved in the conserved processes differed among the platforms. The processes included carbon and nitrogen metabolism, branched-chain amino acid degradation, and hypoxic responses. The data presented herein highlight the potential for various suborbital platforms to contribute insights into biological responses to spaceflight, and further suggest that in-flight fixation during suborbital experiments will enhance insights into responses during each phase of flight.

-Omics studies of plant biology in spaceflight: A critical review of recent experiments

“…As far as research has heretofore determined, the profile of transcriptional changes in response to microgravity includes several themes, the first of which is cell wall synthesis and/or modification. Of the studies examined in this review, Califar et al (2021), Choi et al (2019), Jin et al (2018), Jin et al (2015), Johnson et al (2017), Kruse et al (2020), Manian at al. (2021), Manzano et al (2020), Paul et al (2017), Paul et al (2013b), andVillacampa et al (2021) all found a significant number of DEGs associated with cell wall synthesis and/or modification (Supplementary Table S1).…”

“…Suborbital flights (those which do not reach escape velocity or become artificial satellites around Earth) can provide a reduced gravitational environment for a short time (i.e., a few minutes). Plants were flown on several different types of suborbital flights to determine how their transcriptomes were affected in each environment as compared to those on Earth and in microgravity (Califar et al, 2021). The flights tested included parabolic flights, the Virgin Galactic and Blue Origin suborbital flights, and the F-104 Starfighter flight, all of which create different cycles of hypergravity and microgravity along their flightpath.…”

“…and analyzing the transcriptomes and proteomes, the development of the transcriptomic and proteomic responses to microgravity could be elucidated. The early transcriptional developments could be evaluated using samples collected from suborbital flights, as microgravity is achieved for three to 4 minutes aboard Virgin Galactic and Blue Origin and these flights do cause many of the same transcriptional changes as are observed in spaceflight (Califar et al, 2021).…”

Transcriptomic dynamics in the transition from ground to space are revealed by Virgin Galactic human-tended suborbital spaceflight

“…Virgin Galactic (VG) flies a spaceflight system consisting of a spaceship VSS Unity , along with a mothership, VMS Eve , to perform commercial suborbital flights. This unique platform delivers a suborbital spaceflight profile including a slight hyper- g of horizontal takeoff, a hyper- g during spaceship’s rocket motor boost to space, a 3–4 min microgravity period, and a re-entry with a mixture of hyper- and hypo- g segments prior to landing 1 , 2 . This platform allows customer-defined scientific experimental materials to be flown as automated hardware payloads, and also opens the door to researchers interacting with payloads to conduct experiments.…”

Proposing spacetime scale for space tourism economics

“…Virgin Galactic’s chief space officer, George Whitesides, previously categorized space travel as an “out-of-home luxury experience,” the fastest-growing luxury market (Sheetz, 2021). The pricing varies based on the four levels of space travel—the parabolic flight, like the B727 aircraft; high-altitude flight close to space, like MiG-29 Jet; suborbital flights, like those launched by Virgin Galactic and Blue Origin; and orbital flight, such as flights launched by Space X (Califar et al, 2021; Crouch et al, 2009).

Figure 1.Space travel prices at different altitudes.

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