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Objective: To analyze the long non-coding RNA (lncRNA) and messenger RNA (mRNA) co-expression network changes induced by mtDNA3010A/G mutation in acute hypoxia, and to investigate the role of key lncRNA and mRNA in the regulation of gene expression induced by hypoxia. Methods: The genotype combinations A-C-C and G-C-C of mitochondrial DNA 3010-5178-10400 were screened, and genotypes of mtDNA3010A and mtDNA3010G fusion cells were constructed by using osteosarcoma cell treated by ethidium bromide without mitochondrion (ρ 0 206 cell) as donors. After treatment with 1% O 2 24 h, the lncRNA - mRNA expression chip was applied to detect the differently expressed lncRNA and mRNA in two kinds of fusing cells, and fluorescence quantitative polymerase chain method was used to verify differently expressed mRNA. Bioinformatics methods were applied to build co-expression network of lncRNA-mRNA, predict target genes of differently expressed lncRNA, and the functions of differently expressed mRNA and target genes predicted by lncRNA were also analyzed based on gene ontology (GO) and the Kyoto encyclopedia of genes and genomes (KEGG) forecast analysis. Results: After treatment with 1% O 2 for 24 h, compared with mtDNA3010G fusion cells: 688 lncRNAs were up-regulated, 21 were more than 2 times; 1098 were down-regulated, and 4 were more than 2 times. There were 1151 mRNA expressions up-regulated, 14 were more than 2 times, 539 mRNA expressions were down-regulated, and 3 were more than 2 times. Conclusion: MtDNA3010A/G genotype mutation under hypoxia is able to affect the lncRNA-mRNA regulatory network, and the differentially expressed lncRNA and mRNA may play an important role in regulation network of gene expression induced by hypoxia, which is expected to be a target for the regulation of hypoxia reaction from the perspective of mitochondria.

Objective: To investigate the relationship between mitochondrial DNA (mtDNA) variation and high altitude essential hypertension(HAEH) in the Chinese Tajik population. Methods: Fifty-three patients with HAEH and 46 healthy subjects were enrolled from the Chinese Tajik population. The mtDNA fragments were amplificated by polymerase chain reaction, and products were sequenced to acquire full sequence of mtDNA. The mtDNA sequences of all subjects were compared to the Cambridge sequence to explore mtDNA variations and analyze difference between HAEH and healthy controls. Online softwares were applied to predict function changes caused by positive associated mtDNA variations. Results: Compared to the control group, the frequency of haplogroup U4b was significant higher in HAEH group( P =0.023,OR=7.062,CI(95%)=1.306-38.182), and the frequencies of 8 mutations from haplogroup U4b showed a significant difference between the HAEH group and control group (all with P values below 0.05). The mt DNA15693T＞C mutation was the only missense mutation, which affected amino acid 316 in mitochondrial cytochrome b (MTCYB) by changing it from methionine to threonine. Bioinformatics analysis indicated that the mutation in MTCYB may play a biological role through affecting the second structure of protein. Conclusion: MtDNA subhaplogroup U4b is a genetic factor for HAEH in the Chinese Tajik population, and mtDNA15693T＞C mutation may be an important molecular mechanism of HAEH.

Objective: Highland natives adapt well to the hypoxic environment at high altitude (HA). Several genes have been reported to be linked to HA adaptation. Previous studies showed that the endothelial ni- tric oxide synthase (ENOS) G894T polymorphism contributed to the physiology and pathophysiology of hu- mans at HA by regulating the production of NO. In this meta-analysis, we evaluate the association between the ENOS G894T polymorphism and HA adaptation through analyzing the published data., Methods: We searched all relevant literature about the ENOS G894T polymorphism and HA adaptation in PubMed, Med- line, and Embase before Step 2015. A random-effects model was applied (Revman 5.0), and study quality was assessed in duplicate. Six studies with 634 HA native cases and 621 low-altitude controls were included in this meta-analysis., Results: From the results, we observed that the wild-type allele G was significantly overrepresented in the HA groups (OR = 1.85; 95% Cl, 1.47-2.33; P < 0.0001). In addition, the GG genotype was significantly associated with HA adaptation (OR = 1.99; 95% Cl, 1.54-2.57; P < 0.0001)., Conclusion: Our results showed that in 894 G allele carriers, the GG genotype might be a beneficial factor for HA adaptation through enhancing the level of NO. However, more studies were needed to confirm our findings due to the limited sample size.