We investigated differentially regulated genes in human Jurkat T lymphocytic cells in 20s and 5min microgravity and in hypergravity and compared expression profiles to identify potential gravity-regulated genes and adaptation processes. This dataset is part of a series of three and the other two datasets are deposited in GLDS-172 and GLDS-189.

We investigated differentially regulated and stably expressed genes in human Jurkat T lymphocytic cells in 5min simulated microgravity and hypergravity and compared expression profiles to identify gravity-regulated and unaffected genes as well as adaptation processes. This dataset is part of a series of three and the other two datasets are deposited in GLDS-172 and GLDS-188.

Microgravity or an altered gravity environment from the static 1g has been shown to influence global gene expression patterns and protein levels in cultured cells or animals but it is unclear how these changes in gene and protein expressions are related to each other or are related to other factors regulating such changes. Recent advancement in the field of molecular biology revealed that a different class of RNA the small non-coding microRNA (miRNA) can have a broad effect on gene expression networks by mainly inhibiting the translational process. In this experiment conducted on the International Space Station we propose to test the hypotheses that miRNA profiles will be altered in the space environment and that cellular responses to DNA damage in space are different from those on the ground.

Controlled hypobaria presents biology with an environment that is never encountered in terrestrial ecology yet the apparent components of hypobaria are stresses typical of terrestrial ecosystems. High altitude for example presents terrestrial hypobaria always with hypoxia as a component stress since the relative partial pressure of O2 is constant in the atmosphere. Laboratory-controlled hypobaria however allows the dissection of pressure effects away from the effects typically associated with altitude in particular hypoxia as the partial pressure of O2 can be varied. In this study whole transcriptomes of plants grown in ambient (97 kPa/pO2 = 21 kPa) atmospheric conditions were compared to those of plants transferred to five different atmospheres of varying pressure and oxygen composition for 24 h: 50 kPa/pO2 = 10 kPa 25 kPa/pO2 = 5 kPa 50 kPa/pO2 = 21 kPa 25 kPa/pO2 = 21 kPa or 97 kPa/pO2 = 5 kPa. The plants exposed to these environments were 10 day old Arabidopsis seedlings grown vertically on hydrated nutrient plates. In addition 5 day old plants were also exposed for 24 h to the 50 kPa and ambient environments to evaluate age-dependent responses. The gene expression profiles from roots and shoots showed that the hypobaric response contained more complex gene regulation than simple hypoxia and that adding back oxygen to normoxic conditions did not completely alleviate gene expression changes in hypobaric responses.

Exposure to radiation provokes cellular responses controlled in part by gene expression networks. MicroRNAs (miRNAs) are small non-coding RNAs which mostly regulate gene expression by degrading the messages or inhibiting translation. Here we investigated changes in miRNA expression patterns after low (0.1 Gy) and high (2.0 Gy) doses of X-ray in human fibroblasts. At early (0.5 h) and late (6 and 24 h) time points irradiation caused qualitative and quantitative differences in the down-regulation of miRNA levels including miR-92b 137 660 and 656. A transient up-regulation of miRNAs was observed after 2 h post-irradiation following high doses of radiation including miR-558 and 662. MicroRNA levels were inversely correlated with targets from mRNA and proteomic profiling after 2.0 Gy of radiation. MicroRNAs miR-579 608 548-3p and 585 are noted for targeting genes involved in radioresponsive mechanisms such as cell cycle checkpoint and apoptosis. We suggest here a model in which miRNAs may act as hub regulators of specific cellular responses immediately down-regulated so as to stimulate DNA repair mechanisms followed by up-regulation involved in suppressing apoptosis for cell survival. Taken together miRNAs may mediate signaling pathways in sequential fashion in response to radiation and may serve as biodosimetric markers of radiation exposure. Overall design: The gene expression patterns in human fibroblasts after 2.0 Gy of low-LET radiation was determined at 2 and 24 hrs post-irradiation time in technical triplicates. Control non-irradiated samples were also prepared in triplicates.

We developed a mouse model that captures radiation effects on host biology by transplanting unirradiated Trp53 null mammary tissue to sham or irradiated hosts. Gene expression profiles of tumors that arose in irradiated mice are distinct from those that arose in naive hosts. Host irradiation induces a metaprofile consisting of gene modules representing stem cells cell motility macrophages and autophagy. Human orthologs of the host irradiation metaprofile discriminated between radiation-preceded and sporadic human thyroid cancers. An irradiated host centroid was strongly associated with estrogen receptor negative breast cancer. When applied to sporadic human breast cancers the irradiated host metaprofile strongly associated with basal-like and claudin-low breast cancer intrinsic subtypes. Comparing host irradiation in the context of TGFB levels showed that inflammation was robustly associated with claudin-low tumors. The association of the irradiated host metaprofiles with estrogen receptor negative status and claudin-low subtype suggests that host processes similar to those induced by radiation underlie sporadic cancers. Total RNA was extracted from mammary tumors derived from transplantations of non-irradiated p53null mammary fragments into irradiated hosts. We analyized a total of 32 p53null tumors from irradiated wild type mice: 9 from sham-irradiated hosts and 23 from irradiated hosts. We also analyzed 24 tumors from irradiated TGFb1 heterozygote hosts: 6 from sham-irradiated hosts and 18 from irradiated hosts.

Space radiations and microgravity both could cause DNA damage in cells but the effects of microgravity on DNA damage response to space radiations are still controversial. A mRNA microarray and microRNA microarray in dauer larvae of Caenorhabditis elegans (C. elegans) that endured spaceflight environment and space radiations environment during 16.5-day Shenzhou-8 space mission were performed. In our study wild type and dys-1 mutant strains of C.elegans endured four conditions during shenzhou-8 spaceflight mission including spaceflight static condition(ss) spaceflight 1-g centrifugal condition(sc) ground control condition(gc) and no-transport control. Limited to the quantity of worm samples we performed technical-repeat test but not sample-repeat test. Accordingly eight miRNA microarrays were performed.

We investigated differentially regulated genes in human Jurkat T lymphocytic cells in 20s and 5min microgravity and in hypergravity and compared expression profiles to identify potential gravity-regulated genes and adaptation processes. This dataset is part of a series of three and the other two datasets are deposited in GLDS-188 and GLDS-189.

Ionizing radiations are categorized by linear energy transfer (LET) into low-LET and high-LET. High-LET is considered to have a higher relative biological effectiveness (RBE) than low-LET radiations. However the details of the effects have not been clearly determined. The aim of this study was to characterize the difference between high-LET and low LET radiations. The global effects of the three types of high-LET radiations (fast neutron heavy ion (C) and thermal neutron) were compared with the low-LET radiation (gamma ray) using yeast DNA microarrays. Highly induced genes by the three types of high-LET radiations were those genes related to oxidative stress. Oxidative stress was one of the common factors associated with the four types of radiations. Oxidative stress induced by high-LET radiations may be more serious than that induced by gamma rays. Additionally genes related to protein synthesis and the ubiquitin and proteasome system were detected. This suggests that more protein damages can be induced by high-LET radiation that denatures the proteins in yeast cells. The genes specifically altered by each type of high-LET radiation were also studied. Overall design: This series contains 4 kinds of irradiation-induced gene expression profiles. Triplicates hybridization was done in each irradiation exposure and each array have high and low power scanned data respectively. All biological samples were collected independently.

Mice were flown onboard STS-135 and returned to Earth for analysis. Livers were collected within 3-4 hours of landing and snap frozen in liquid nitrogen. Samples were shipped to UCI Genomics High Throughput Facility for analysis.