Study protein expression, enzyme functions, and proteomic changes in organisms exposed to spaceflight conditions.
Study reveals that tardigrade Secretory-Abundant Heat Soluble (SAHS) proteins act as potent extracellular stabilizers, protecting cellular membranes from dehydration damage. These findings present a new class of biopreservatives with significant potential for stabilizing microbial systems for agriculture and space-based life support.
A study on mice exposed to simulated galactic cosmic rays (GCR) reveals long-term changes in heart and plasma proteins 8 months post-exposure. A key finding is the activation of pathways leading to Neutrophil Extracellular Traps (NETs) in heart tissue, a process linked to inflammation, tissue damage, and thrombosis, highlighting a significant cardiovascular risk for long-duration space missions.
Researchers have identified and localized a new protein, AtGTLP, in the model plant Arabidopsis thaliana. This protein resides in the trans-Golgi apparatus and is predicted to be a glycosyltransferase, an enzyme critical for cell wall biosynthesis and protein modification, providing foundational knowledge for plant-based life support systems in space.
This study demonstrates that desiccation significantly increases harmful reactive oxygen species (ROS) in tardigrades. Using RNA interference, researchers identified that the antioxidant enzyme glutathione peroxidase is essential for survival, while other enzymes and aquaporin proteins are crucial for successful rehydration, highlighting a complex, synergistic defense mechanism.
Fruit flies born and raised on the ISS showed significant cardiac dysfunction, including reduced contractility and output. This study reveals that microgravity triggers extensive cardiac remodeling, downregulates structural genes, and dramatically upregulates genes for protein degradation, indicating a state of 'proteostatic stress' that may be a fundamental response of heart muscle to spaceflight.
A comprehensive analysis of liver tissue from mice on multiple space missions reveals that spaceflight consistently disrupts lipid metabolism. These changes, driven by key regulators like HNF4α and PPARα, resemble the early stages of non-alcoholic fatty liver disease (NAFLD), highlighting a potential health risk for long-duration space travel.
Multi-mission analysis of mice flown on the ISS reveals that spaceflight alone, independent of re-entry stress, causes significant lipid accumulation in the liver. This dysregulation, confirmed through transcriptomics and proteomics, points to early signs of non-alcoholic fatty liver disease (NAFLD), highlighting a potential health risk for astronauts on long-duration missions.
An ex vivo study on mouse vertebrae reveals that high-dose ionizing radiation (≥5,000 Gy) significantly reduces bone strength and fatigue life by causing collagen fragmentation. Increased collagen crosslinking, observed even at low doses, did not correlate with mechanical weakness, clarifying a key mechanism of radiation damage to bone.
Analysis of GeneLab data from ground and spaceflight experiments suggests a novel protective mechanism where space radiation activates the FYN kinase, which in turn reduces harmful reactive oxygen species (ROS) in cardiovascular cells. This finding, which identifies protons as the dominant radiation source in LEO, is critical for modeling long-term astronaut heart health and developing targeted countermeasures.
An evaluation of NASA's GeneLab and four other omics data systems against 14 FAIR principles (Findability, Accessibility, Interoperability, Reusability) revealed strong performance in data accessibility but significant shortcomings in interoperability. The study highlights the need for improved semantic standards to enhance data integration and reuse, a critical goal for accelerating space bioscience research.
This review synthesizes current knowledge on the plant endoplasmic reticulum (ER), highlighting its critical role as a sensor and mediator of cellular stress. By managing protein quality, initiating signaling pathways, and influencing cell fate, the ER is fundamental to plant adaptation, with major implications for developing resilient crops for space missions.
A 15-day spaceflight study in mice reveals that microgravity causes rapid bone loss through three distinct mechanisms: increased bone resorption by osteoclasts, active bone degradation by osteocytes (osteocytic osteolysis), and inhibition of new bone formation via p21-mediated cell cycle arrest in osteoblasts. These findings identify novel targets for countermeasures against bone loss on long-duration missions.
By creating hybrid channels from E. coli and S. aureus, researchers identified a single amino acid at the protein-lipid interface that controls how bacterial mechanosensitive channels (MscL) respond to pressure. This 'molecular spring' dictates both the sensitivity and duration of the channel's opening, providing a fundamental insight into how cells sense mechanical forces.
This review details the function of two critical protein families, MscS and MscL, which act as mechanosensitive channels to protect microbes from bursting under sudden osmotic stress. These channels serve as 'emergency release valves,' a fundamental survival mechanism with significant implications for controlling microbial life in space environments.
Using disulfide trapping and electrophysiology in E. coli, this study maps the dynamic interactions within the MscL mechanosensitive channel. The findings reveal how specific protein domains move during channel opening, either locking it closed or stabilizing partially open states, providing a detailed model for how cells regulate internal pressure.
Researchers demonstrated three distinct, reversible methods to control the pore size of the bacterial MscL channel, effectively turning it into a tunable nanovalve. By genetically modifying a key structural linker, they could precisely reduce ion flow, a finding with major implications for developing on-demand drug delivery systems and advanced biosensors for space missions.
This study resolves a key controversy about the structure of the mechanosensitive channel MscL, a protein vital for cellular pressure regulation. Using an in vivo disulfide-trapping technique, researchers demonstrated that the channel is a pentamer in its native membrane, and that the previously reported tetrameric structure was an artifact of detergent use during crystallization.
This study demonstrates that introducing electrical charges into the pore of the bacterial MscL channel not only gates it but also selectively controls the passage of large charged molecules. This finding is critical for developing triggerable nanovalves for targeted drug delivery, with potential applications in delivering medical countermeasures during space missions.
This study resolves a structural controversy by demonstrating that the bacterial mechanosensitive channel SaMscL is a five-subunit (pentameric) complex in its native cell membrane. It reveals that the four-subunit (tetrameric) structure previously reported was an artifact induced by the specific detergent used for in vitro analysis, highlighting a critical methodological pitfall for membrane protein research.