Project description:BACKGROUND: Human SP-A1 and SP-A2, encoded by SFTPA1 and SFTPA2 and their genetic variants differentially impact alveolar macrophage (AM) functions and regulation, including the miRNome. We investigated whether miRNome differences previously observed between AM from SP-A2 and SP-A1/SP-A2 mice are due to continued qualitative differences or a delayed response of mice carrying a single gene. METHODS: Human transgenic (hTG) mice, carrying SP-A2 or both SP-A genes and SP-A-KO mice were exposed to filtered air (FA) or O3. AM miRNA levels, target gene expression and pathways determined 18 h after O3 exposure. RESULTS: We found: (a) Differences in miRNome due to sex, SP-A genotype, and exposure; (b) miRNome of both sexes was largely downregulated by O3 ; co-ex had fewer changed (≥2X) miRNAs than either group. (c) the number and direction of expression of genes with significant changes in males and females in co-ex is almost the opposite of those in SP-A2; (iv) The same pathways were found in the studied groups; (e) O3 exposure attenuated sex differences; a higher number of genotype-dependent and genotype-independent miRNAs was common in both sexes after O3 exposure. CONCLUSION: Qualitative differences between SP-A2 and co-ex persist 18 h post-O3, and O3 attenuates sex differences.
Project description:In humans there are two surfactant protein A (SP-A) functional genes SFTPA1 and SFTPA2 encoding innate immune molecules, SP-A1 and SP-A2, respectively, with numerous genetic variants each. SP-A interacts and regulates many of the functions of alveolar macrophages (AM). It is shown that SP-A variants differ in their ability to regulate the AM miRNome in response to oxidative stress (OxS). Because humans have both SP-A gene products, we were interested to determine the combined effect of co-expressed SP-A1/SP-A2 (co-ex) in response to ozone (O3) induced OxS on AM miRNome. Human transgenic (hTG) mice, carrying both SP-A1/SP-A2 (6A2/1A0, co-ex) and SP-A- KO were utilized. The hTG and KO mice were exposed to filtered air (FA) or O3 and miRNA levels were measured after AM isolation with or without normalization to KO. We found: (i) The AM miRNome of co-ex males and females in response to OxS to be largely downregulated after normalization to KO, but after Bonferroni multiple comparison analysis only in females the AM miRNome remained significantly different compared to control (FA); (ii) The targets of the significantly changed miRNAs were downregulated in females and upregulated in males; (iii) Several of the validated mRNA targets were involved in pro-inflammatory response, anti-apoptosis, cell cycle, cellular growth and proliferation; (iv) The AM of SP-A2 male, shown, previously to have major effect on the male AM miRNome in response to OxS, shared similarities with the co-ex, namely in pathways involved in the pro-inflammatory response and anti-apoptosis but also exhibited differences with the cell-cycle, growth, and proliferation pathway being involved in co-ex and ROS homeostasis in SP-A2 male. We speculate that the presence of both gene products versus single gene products differentially impact the AM responses in males and females in response to OxS.
Project description:Proteins from Mortierella elongata/Candidatus Glomeribacter sp. symbiotic system were extracted, trypsine digested and identified with LC-MS/MS analysis.
Project description:Transcriptomic sequencing was performed to obtain the key functional genes involved in the adaptation of oxidative stress induced by hydrogen peroxide (H2O2) in the Arctic bacterium Pseudoalteromonas sp. A2. Exposure to 1 mmol/L H2O2 resulted in large alterations of the transcriptome profile, including significant upregulation of 109 genes and significant downregulation of 174 genes. Functional classification of differentially expressed genes revealed that most of genes affiliated with biological adhesion, negative regulation of biological process, enzyme regulator activity, protein binding transcription factor activity and structural molecular activity were upregulated, and most of genes affiliated with multicellular organismal process and extracellular region were downregulated. It was notably that fifteen genes affiliated with flagella and four genes affiliated with heat shock proteins were significantly upregulated. Meanwhile, nine genes affiliated with cytochrome and cytochrome oxidase, and five genes affiliated with TonB-dependent receptor, were significantly downregulated. However, eighteen genes with antioxidant activity categorized by GO analysis showed differential expressions. This overall survey of transcriptome and oxidative stress-relevant genes can contribute to understand the adaptive mechanism of Arctic bacteria. five significant upregulated genes and five significant downregulated genes were selected using qRT-PCR to cinduct the oxidative stress. overall survey of transcriptomic sequencing by RNA-Seq of the Pseudoalteromonas sp. A2, an isolate from seawater with high activity against H2O2