The aim of this work is to determine whether mycobacteria have enhanced virulence during space travel and what mechanisms they use to adapt to microgravity. M. marinum and LHM4 were grown in high aspect ratio vessels (HARV) in a rotary cell culture system (RCCS) under normal gravity (NG) or low shear simulated microgravity (MG). To determine the effect of MG on the stress responses activated by the growth conditions we used RNAseq to examine what genes were expressed. For RNAseq the bacteria are harvested RNA isolated and converted DNA (cDNA) and the cDNA sequenced. Using bioinformatics the amount of expression of the different M. marinum genes were compared between the NG and MG samples. To make sure that we were examining only gene expression changes due to MG only bacteria in early exponential growth were used in the RNAseq studies. Triplicate NG and MG cultures were used to generate samples of bacteria grown for ~40 hrs. We also grew triplicate cultures for 4 days and then diluted them again and grew them for another ~40 hrs so we could examine gene expression from bacteria exposed for a longer time. In summary this study determined that waterborne mycobacteria alter their growth expression of stress responses and their sensitivity to oxidizing conditions when subjected to growth under MG.

Spaceflight imposes numerous adaptive challenges for terrestrial life. The reduction in gravity or microgravity represents a novel environment that can disrupt homeostasis of many physiological processes. Additionally it is becoming increasingly clear that an organism s microbiome is critical for host health and examining its resiliency in microgravity represents a new frontier for space biology research. In this study we examine the impact of microgravity on the interactions between the squid Euprymna scolopes and its beneficial symbiont Vibrio fischeri which form a highly specific binary mutualism. First animals inoculated with V. fischeri aboard the space shuttle showed effective colonization of the host light organ the site of the symbiosis during spaceflight. Second RNA-Seq analysis of squid exposed to modeled microgravity conditions exhibited extensive differential gene expression in the presence and absence of the symbiotic partner. Transcriptomic analyses revealed in the absence of the symbiont during modeled microgravity there was an enrichment of genes and pathways associated with the innate immune and oxidative stress response. The results suggest that V. fischeri may help modulate the host stress responses under modeled microgravity. This study provides a window into the adaptive responses that the host animal and its symbiont use during modeled microgravity.

['Microgravity is one of the most important features in spaceflight. Previous evidence has shown that significant changes to the musculoskeletal and immune systems occurred under microgravity. The present study was undertaken to explore the change in protein abundance in human colon colorectal cells that were incubated for 48 or 72 h either in normal conditions and µG simulated conditions. The comparative proteomic method based on the 18O labeling technique was applied to investigate the up-regulated proteins and down-regulated proteins in SH-SY5Y under simulated microgravity.']

Spaceflight imposes numerous adaptive challenges for terrestrial life. The reduction in gravity, or microgravity, represents a novel environment that can disrupt homeostasis of many physiological processes. Additionally, it is becoming increasingly clear that an organism's microbiome is critical for host health and examining its resiliency in microgravity represents a new frontier for space biology research. In this study, we examine the impact of microgravity on the interactions between the squid Euprymna scolopes and its beneficial symbiont Vibrio fischeri, which form a highly specific binary mutualism. First, animals inoculated with V. fischeri aboard the space shuttle showed effective colonization of the host light organ, the site of the symbiosis, during spaceflight. Second, RNA-Seq analysis of squid exposed to modeled microgravity conditions exhibited extensive differential gene expression in the presence and absence of the symbiotic partner. Transcriptomic analyses revealed in the absence of the symbiont during modeled microgravity there was an enrichment of genes and pathways associated with the innate immune and oxidative stress response. The results suggest that V. fischeri may help modulate the host stress responses under modeled microgravity. This study provides a window into the adaptive responses that the host animal and its symbiont use during modeled microgravity.

To reveal outcomes of microgravity on molecular processes within the cellular environment we have employed a mass-spectrometry based proteomics approach. Proteomics analysis based on mass spectrometry allows for the relative quantitation of a large number of proteins concurrently and in a relatively unbiased manner. Mass spectrometry based proteomics can be rendered even more informative by addition of a labeling component to understand the dynamics of the changing protein content. In this study we utilized a combination of proteomics techniques namely label-free quantification and dynamic stable-isotope labeling by amino acids in cell culture (Dynamic SILAC) to characterize the microgravity stress response in primary cardiomyocytes.

The goal of this study was to assess whether low shear-modeled microgravity (LSMMG) affects yeast genomic expression patterns using the powerful tool of whole genome microarray hybridization. We determined changes in the yeast model organism, Saccharomyces cerevisisae, when grown in LSMMG using the rotating High Aspect Ratio Vessel (HARV). A significant number of genes were up- or down-regulated by at least two fold in cells that were grown for 5 generations or 25 generations in HARVs. We identified genes in cell wall integrity signaling pathways containing MAP kinase cascades that may provide clues to novel physiological responses of eukaryotic cells to the external stress of a low-shear modeled microgravity environment. A comparison of the microgravity response to other environmental stress response (ESR) genes showed that 26% of the genes that respond ,significantly to LSMMG are involved in a general environmental stress response, while 74% of the genes may represent a unique transcriptional response to microgravity. In addition, we found changes in genes involved in budding, cell polarity establishment, and cell separation that confirm our hypothesis that exposure to LSMMG causes changes in gene transcription resulting in a phenotypic response. The results of the study provide interesting clues to potential mechanisms involved in the response to, adaptation to, and survival of eukaryotic cells in a microgravity environment and our findings may have important health implications for human spaceflight. Experiment Overall Design: Four conditions are compared with three replicates each: yeast grown in low-shear modeled microgravity (HARV bioreactor) for 5 and 25 generations; yeast grown in a horizontal (non-LSMMG) HARV bioreactor for 5 and 25 generations.

This study demonstrates simulated microgravity effects on E. coli K 12 MG1655 when grown on LB medium supplemented with glycerol. The results imply that E. coli readily reprograms itself to combat the multiple stresses imposed due to microgravity. Under these conditions it survives by upregulating oxidative stress protecting genes and simultaneously down regulating the membrane transporters and synthases to maintain cell homeostasis. In this study a clinostat that mimics microgravity conditions was used to investigate the effects of microgravity on E. coli grown in LB medium supplemented with glycerol to monitor the effects on growth and global gene expression using Affymetrix DNA microarrays.

These investigations studied the fundamentals of how plants perceive gravity and develop in microgravity. It informs how gene regulation is altered by spaceflight conditions.

Microgravity effect on C. elegans gene expression was analysed by whole genome microarray. The worms were cultivated under microgravity for 4 days in the Japanese Module of the International Space Station. C. elegans N2 was exposed microgravity for 4 days. The worms synchronously were cultivated from L1 larvae to adult. There are two control groups onboard 1G and ground 1G control.

Microgravity effect on C. elegans gene expression was analysed by whole genome microarray. The worms were cultivated under microgravity for 4 days in the Japanese Module of the International Space Station. C. elegans N2 was exposed microgravity for 4 days. The worms synchronously were cultivated from L1 larvae to adult. There are two control groups onboard 1G and ground 1G control.