Expression of miRNA, lncRNA and mRNA in human lymphoblastoid TK6 cells under simulated microgravity after ionizing radiation

In space, multiple unique environmental factors, particularly microgravity and space radiation, pose constant threat to the astronaut’s health. To gain insight into the role of miRNAs and lncRNAs in response to radiation and microgravity, we analyzed RNA expression profiles in human lymphoblastoid TK6 cells incubated for 24 h in static condition or in rotating condition to stimulate microgravity in space after 2 Gy γ-ray irradiation. Expression of 14 lncRNAs and 17 mRNAs was found to be significantly down-regulated in the simulated microgravity condition. In contrast, irradiation up-regulated the expression of 55 lncRNAs and 56 mRNAs, while only one lncRNA, but no mRNA, was down-regulated. Furthermore, 2 miRNAs, 70 lncRNAs, and 87 mRNAs showed significantly altered expression under simulated microgravity after irradiation, and these changes were independently induced by irradiation and simulated microgravity. Together, our results indicate that simulated microgravity and irradiation additively and independently alter the expression of RNAs and their target genes in human lymphoblastoid cells. Human lymphoblastoid TK6 cells were incubated for 24 h in static condition without (Control) or with 2 Gy ionizing radiation (IR), rotating condition to simulate microgravity (MG) in space using Rotary Cell Culture Systems (Synthecon, Houston, TX, US), or rotating condition after ionizing radiation with γ-rays (MG + IR). Then total RNA were extracted for hybridization on Affymetrix microarrays.