LncRNA NEAT1 promotes apoptosis and inflammation in LPS-induced sepsis models by targeting miR-590-3p
EXPERIMENTAL AND THERAPEUTIC MEDICINE
Authors: Liu, Lingling; Liu, Fengtao; Sun, Zhilu; Peng, Zhengliang; You, Ting; Yu, Ziying
Abstract
Sepsis is a complication of infection caused by disease or trauma. Increasing evidence have shown that long noncoding RNAs (lncRNAs) are involved in the regulation of sepsis. However, the mechanism of lncRNA nuclear enriched abundant transcript 1 (NEAT1) in the regulation of sepsis progression remains to be elucidated. Lipopolysaccharide (LPS) was used to induce a sepsis cell model. The expression levels of NEAT1 and microRNA (miR)-590-3p were determined by reverse transcription-quantitative PCR. Cell viability and apoptosis were detected using Cell Counting Kit-8 (CCK-8) assay and flow cytometry, respectively. Western blot analysis was performed to evaluate the levels of apoptosis- and NF-kappa B signaling pathway-related proteins. The concentration of inflammatory cytokines was determined using ELISA. In addition, dual-luciferase reporter assay, RNA immunoprecipitation and biotin-labeled RNA pull-down assay were performed to verify the interaction between NEAT1 and miR-590-3p. The results showed that NEAT1 was highly expressed in patients with sepsis and LPS-induced H9c2 cells. Knockdown of NEAT1 decreased LPS-induced cell apoptosis and inflammation response in H9c2 cells. Meanwhile, miR-590-3p showed decreased expression in sepsis, and its overexpression could relieve LPS-induced H9c2 cell damage. Further experiments revealed that NEAT1 could sponge miR-590-3p. Knockdown of miR-590-3p reversed the inhibitory effect of NEAT1 knockdown on LPS-induced H9c2 cell damage. Additionally, the NEAT1/miR-590-3p axis could regulate the activity of the NF-kappa B signaling pathway. To conclude, lncRNA NEAT1 accelerated apoptosis and inflammation in LPS-stimulated H9c2 cells via sponging miR-590-3p. These findings may provide a new strategy for the treatment of sepsis.
An efficient single-cell transcriptomics workflow for microbial eukaryotes benchmarked on Giardia intestinalis cells
BMC GENOMICS
Authors: Onsbring, Henning; Tice, Alexander K.; Barton, Brandon T.; Brown, Matthew W.; Ettema, Thijs J. G.
Abstract
BackgroundMost diversity in the eukaryotic tree of life is represented by microbial eukaryotes, which is a polyphyletic group also referred to as protists. Among the protists, currently sequenced genomes and transcriptomes give a biased view of the actual diversity. This biased view is partly caused by the scientific community, which has prioritized certain microbes of biomedical and agricultural importance. Additionally, some protists remain difficult to maintain in cultures, which further influences what has been studied. It is now possible to bypass the time-consuming process of cultivation and directly analyze the gene content of single protist cells. Single-cell genomics was used in the first experiments where individual protists cells were genomically explored. Unfortunately, single-cell genomics for protists is often associated with low genome recovery and the assembly process can be complicated because of repetitive intergenic regions. Sequencing repetitive sequences can be avoided if single-cell transcriptomics is used, which only targets the part of the genome that is transcribed.ResultsIn this study we test different modifications of Smart-seq2, a single-cell RNA sequencing protocol originally developed for mammalian cells, to establish a robust and more cost-efficient workflow for protists. The diplomonad Giardia intestinalis was used in all experiments and the available genome for this species allowed us to benchmark our results. We could observe increased transcript recovery when freeze-thaw cycles were added as an extra step to the Smart-seq2 protocol. Further we reduced the reaction volume and purified the amplified cDNA with alternative beads to test different cost-reducing changes of Smart-seq2. Neither improved the procedure, and reducing the volumes by half led to significantly fewer genes detected. We also added a 5 biotin modification to our primers and reduced the concentration of oligo-dT, to potentially reduce generation of artifacts. Except adding freeze-thaw cycles and reducing the volume, no other modifications lead to a significant change in gene detection. Therefore, we suggest adding freeze-thaw cycles to Smart-seq2 when working with protists and further consider our other modification described to improve cost and time-efficiency.Conclusions p id=Par The presented single-cell RNA sequencing workflow represents an efficient method to explore the diversity and cell biology of individual protist cells.