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

Abstract

Researchers have been studying transcriptomic and proteomic responses of plants to ranges of reduced gravitational conditions. These include blue and red light in microgravity, circadian rhythms in microgravity, microgravity in different ecotypes, microgravity on suborbital flights, and they have using a variety of experimental equipment. Recent findings have linked microgravity and transcriptomic changes in genes relating to cell wall synthesis and modification, oxidative stress, abiotic stressors, phytohormones, sugar synthesis and metabolism, ribosomal biogenesis, and plant defense to other organisms. Although we have a better-established profile of the transcriptomic response of plants to reduced gravity, some areas of study have not yet been thoroughly investigated. The initial stages and progression of transcriptional responses to microgravity, the responses of additional plant species, and tissue-specific transcriptional responses to microgravity should all be further investigated in order to better develop our understanding of how plants react to a reduced gravity environment. In the near future, advancing technology, rapidly growing databases, and an increasing number of spaceflight opportunities will allow for more research to be conducted to address these and many other related questions in plant space biology.

Design of Spaceflight Hardware for Plant Growth in a Sealed Habitat for Experiments on the Moon

“…Based on our results, we can answer the four questions listed above related to plant growth in a small, sealed chamber. genes and biosynthetic pathways when compared to 1g controls (Herranz et al, 2019;Vandenbrink et al, 2019;Hughes and Kiss, 2022). For example, in microgravity, light-associated pathways related to photosynthesis and the chlorophyll metabolism were significantly downregulated (Vandenbrink et al, 2019).…”

“…In the longer term, once we move past these basic experiments, we will be able to expand the use of the hardware to perform experiments of greater complexity. For instance, if we are able to have sample return, then we can do a series of gene-profiling experiments to understand how gene expression in plants changes relative to the lunar environment (Vandenbrink et al, 2019;Hughes and Kiss, 2022). In the long term, this knowledge would help us to genetically modify plants to optimize growth and development on the lunar surface.…”

“…There are very little data to show how plants will grow in the partial gravity and high radiation environment on the surface of the Moon or Mars (reviewed in Kiss, 2014). The vast literature on the growth of plants on Earth has been augmented by a rapidly increased knowledge of plant growth in microgravity (Vandenbrink and Kiss, 2016;Hughes and Kiss, 2022). In comparison, we know little about plant behavior in reduced (sometimes termed fractional) gravity environments (less than the nominal 1g that occurs on Earth).…”

Light has a principal role in the physiological adaptation of plants to the spaceflight environment

“…Experiments have also revealed the dramatic impact of light wavelengths on the morphology of Arabidopsis seedlings grown in microgravity and fractional gravity 6,9,10 . Due to space facility limitations, as well as payload capacity in space ight, most of plant transcriptomic analyses have been performed using either constant light or constant dark conditions 8, [11][12][13][14] . While extensive analyses have been conducted on plants cultivated in various space ight-associated environments, including some experiments without light, direct comparisons of light vs dark growth in space in the same experiment are available only for the CARA experiment 15 .…”

Integrative transcriptomics and proteomics profiling of Arabidopsis thaliana elucidates novel mechanisms underlying spaceflight adaptation

“…In their diversity, these studies have accumulated an extensive array of phenotypic characterizations and uncovered some of the fundamental concepts related to physiological adaptation in space ( Kordyum and Hasenstein, 2021 ). However, the traditional approaches have recently been complemented and in many ways superseded by the advent of genomic, transcriptomic, and proteomic methods, setting the stage for high throughput analyses that investigates the effects of spaceflight on plants from a molecular and functional perspective ( Hughes and Kiss, 2022 ). This allows the physiological effects of the spaceflight environment to be characterized beyond phenotyping and extensively mapped out along broader biochemical pathways and cryptic signaling molecular cascades.…”