1.College of Biotechnology of Guilin Medical University;2.Institute of Medical Service and Technology, Academy of Military Sciences
目的 微重力环境影响骨代谢进程与miRNA的表达，然而，微重力环境下miRNA调控成骨细胞分化的潜在机制仍不清楚，本研究旨在探讨微重力环境对MC3T3-E1成骨细胞影响。方法 本研究采用转录组测序技术（RNA-seq）观察微重力培养前后MC3T3-E1成骨细胞的miRNA/mRNA表达谱变化，测序结果采用Q-PCR验证。采用生物信息学的方法进一步研究差异性表达的miRNA/mRNA。结果 与对照组（CON）相比，模拟微重力组（SMG）共有160条miRNA和1912个mRNAs发生显著改变；根据生物信息学结果，筛选出10个关键性基因（3 miRNA、7 mRNA），其中miR-9_6666-5p为微重力敏感miRNA，可能在微重力环境下成骨细胞分化过程中起到重要的作用。结论 微重力环境下，成骨细胞分化受到抑制，我们的结果将有助于深入理解miRNA与mRNA在微重力环境下调控成骨分化与骨生成的分子机制。
Objective Micro-gravity affects the process of bone metabolism and miRNA level of expression. However, the molecular mechanism underlying the alterations of cellular activity and miRNA under the micro-gravity is not fully understood. The aim of this study is to investigate the effect of micro-gravity on MC3T3-E1 cells. Methods The differential miRNA and mRNA expression profiling of MC3T3-E1 cells during exposure to micro-gravity were established by RNA transcriptome sequencing technology (RNA-seq). The RNA sequencing results were validated using quantitative real-time polymerase chain reaction (Q-PCR). Bioinformatic analyses were applied for further study of these differentially expressed miRNAs and mRNAs. Results A total of 1912 coding transcripts and 160 miRNAs were detected along with osteogenic differentiation under conditions of micro-gravity. Bioinformatic analysis revealed 10 core regulatory genes including 7 mRNAs and 3 miRNAs. Based on the analysis and verification, we identified one miRNA, miR-9_6666-5p, which is likely to play important roles in osteogenic differentiation process under micro-gravity. Conclusion The present study showed that the process of osteoblast differentiation was repressed. Our results could lead to a better understanding of the molecular mechanisms of genes and miRNAs, and their cooperation underlying the effects of micro-gravity on osteogenic differentiation and bone formation.