Multiple waves of transcriptome changes during extended hypoxic induction in human pulmonary microvascular endothelial cells
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ABSTRACT: We profile the expression pattern of human pulmonary microvascular endothelial cells (HPMECs) at different time points of hypoxic stress. Through mRNA-seq, we identify functional waves of minor gene up-regulation at 8 and 24h hypoxia exposure followed by a massive wave of transcriptional activation after 48 hours. By weighted gene co-expression network analysis, we identify hub genes that likely play central roles in hypoxia transcription program. Strikingly, these hub genes included a prominent group of lincRNAs, suggesting non-coding RNAs may also have pivotal roles in the hypoxia regulatory circuit. HPMECs share a core hypoxia signature profile, but with some notably differences, indicating a portion of HPMECs hypoxia response is cell-specific. Collectively, our study comprehensive surveys the hypoxia transcriptome, and provides insight into the temporal dynamics of hypoxia transcriptional response. Time-course expression profiling of HPMECs exposed to hypoxia
Project description:We profile the expression pattern of human pulmonary microvascular endothelial cells (HPMECs) at different time points of hypoxic stress. Through mRNA-seq, we identify functional waves of minor gene up-regulation at 8 and 24h hypoxia exposure followed by a massive wave of transcriptional activation after 48 hours. By weighted gene co-expression network analysis, we identify hub genes that likely play central roles in hypoxia transcription program. Strikingly, these hub genes included a prominent group of lincRNAs, suggesting non-coding RNAs may also have pivotal roles in the hypoxia regulatory circuit. HPMECs share a core hypoxia signature profile, but with some notably differences, indicating a portion of HPMECs hypoxia response is cell-specific. Collectively, our study comprehensive surveys the hypoxia transcriptome, and provides insight into the temporal dynamics of hypoxia transcriptional response.
Project description:Physiological shear stress, produced by blood flow, homeostatically regulates the phenotype of pulmonary endothelial cells exerting anti-inflammatory and anti-thrombotic actions and maintaining normal barrier function. In the pulmonary circulation hypoxia, due to high altitude or diseases such as COPD, causes vasoconstriction, increased vascular resistance and pulmonary hypertension. Hypoxia-induced changes in endothelial function play a central role in the development of this pulmonary hypertension. However, the direct interactive effects of hypoxia and shear stress on the pulmonary endothelial phenotype have not been extensively studied. We cultured human pulmonary microvascular endothelial cells (HPMEC) in normoxia or hypoxia while subjected to physiological shear stress or in static conditions. Unbiased proteomics was used to identify hypoxia-induced changes in protein expression. Using publicly available single cell RNA-seq datasets, differences in gene expression between the alveolar endothelial cells from COPD and healthy lungs were identified. 60 proteins were identified in HPMEC lysates whose expression changed in response to hypoxia in sheared but not in static conditions. mRNA for five of these (ERG, MCRIP1, EIF4A2, HSP90AA1 and DNAJA1) showed similar changes in the endothelial cells of COPD compared to healthy lungs. These data show that the proteomic responses of the pulmonary microvascular endothelium to hypoxia are significantly altered by shear stress and suggest that these differences are important in the development of hypoxic pulmonary vascular disease.
Project description:There is marked sexual dimorphism displayed in the onset and progression of pulmonary hypertension (PH). Females more commonly develop pulmonary arterial hypertension (PAH), however, females with PAH and other types of PH have better survival than males. Pulmonary microvascular endothelial cells play a crucial role in the pulmonary vascular remodelling and increased pulmonary vascular resistance of PH. Given this background, we hypothesized that there are sex differences in the pulmonary microvascular endothelium basally and in response to hypoxia that are independent of the sex hormone environment.
Project description:The goal of this study was to gain insight into the molecular heterogeneity of capillary endothelial cells derived from different organs by microarray profiling of freshly isolated cells and identify transcription factors that may determine the specific gene expression profile of endothelial cells from different tissues. The study focused on heart endothelial cells and presents a validated signature of 31 genes that are highly enriched in heart endothelial cells. Within this signature 5 transcription factors were identified and the optimal combination of these transcription factors was determined for specification of the heart endothelial fingerprint. From three tissue types (mouse brain, heart and liver), we collected five freshly isolated endothelial cell samples each. For each brain sample we pooled RNA from 6 mice. For each heart sample we pooled RNA from 4 mice. For each liver sample we pooled RNA from 2 mice. The three endothelial subtypes were then compared. For each subtype, specific gene profiles were defined by determining the genes that were highly enriched versus the other two endothelial subtypes.
Project description:Background: LincRNAs play critical roles in eukaryotic cells, but systematic analyses of lincRNAs of an animal for phenotypes have been missing. We have generated CRISPR knockout strains for C. elegans lincRNAs and have evaluated their phenotypes Results: C. elegans lincRNAs demonstrate global features such as shorter length and fewer exons than mRNAs. For the systematic evaluation of C. elegans lincRNAs, CRISPR knockout strains for 155 out of all the 170 C. elegans lincRNAs were produced. Mutants of 23 lincRNAs have shown phenotypes in 6 traits analyzed. We have investigated these phenotypic lincRNAs for their gene expression patterns and their potential functional mechanisms. Some C. elegans lincRNAs play cis roles to modulate the expression of their neighboring genes, and some other lincRNAs play trans roles as ceRNAs against microRNAs. LincRNAs are extensively regulated by transcription factors, and we dissect the pathway that two transcription factors UNC-30 and UNC-55 control the expression of linc-73 together. Furthermore, linc-73 plays a cis role to modulate the expression of its neighboring gene unc-104, and thus regulates the formation of presynapses. Conclusions: By using CRISPR/cas9 technology, we have generated knockout strains of 155 C. elegans lincRNAs as valuable resources for studies in noncoding RNAs, and we provide biological insights for 23 phenotypic lincRNAs identified from 6 traits examined.
Project description:Background: LincRNAs play critical roles in eukaryotic cells, but systematic analyses of lincRNAs of an animal for phenotypes have been missing. We have generated CRISPR knockout strains for C. elegans lincRNAs and have evaluated their phenotypes Results: C. elegans lincRNAs demonstrate global features such as shorter length and fewer exons than mRNAs. For the systematic evaluation of C. elegans lincRNAs, CRISPR knockout strains for 155 out of all the 170 C. elegans lincRNAs were produced. Mutants of 23 lincRNAs have shown phenotypes in 6 traits analyzed. We have investigated these phenotypic lincRNAs for their gene expression patterns and their potential functional mechanisms. Some C. elegans lincRNAs play cis roles to modulate the expression of their neighboring genes, and some other lincRNAs play trans roles as ceRNAs against microRNAs. LincRNAs are extensively regulated by transcription factors, and we dissect the pathway that two transcription factors UNC-30 and UNC-55 control the expression of linc-73 together. Furthermore, linc-73 plays a cis role to modulate the expression of its neighboring gene unc-104, and thus regulates the formation of presynapses. Conclusions: By using CRISPR/cas9 technology, we have generated knockout strains of 155 C. elegans lincRNAs as valuable resources for studies in noncoding RNAs, and we provide biological insights for 23 phenotypic lincRNAs identified from 6 traits examined.
Project description:Background: LincRNAs play critical roles in eukaryotic cells, but systematic analyses of lincRNAs of an animal for phenotypes have been missing. We have generated CRISPR knockout strains for C. elegans lincRNAs and have evaluated their phenotypes Results: C. elegans lincRNAs demonstrate global features such as shorter length and fewer exons than mRNAs. For the systematic evaluation of C. elegans lincRNAs, CRISPR knockout strains for 155 out of all the 170 C. elegans lincRNAs were produced. Mutants of 23 lincRNAs have shown phenotypes in 6 traits analyzed. We have investigated these phenotypic lincRNAs for their gene expression patterns and their potential functional mechanisms. Some C. elegans lincRNAs play cis roles to modulate the expression of their neighboring genes, and some other lincRNAs play trans roles as ceRNAs against microRNAs. LincRNAs are extensively regulated by transcription factors, and we dissect the pathway that two transcription factors UNC-30 and UNC-55 control the expression of linc-73 together. Furthermore, linc-73 plays a cis role to modulate the expression of its neighboring gene unc-104, and thus regulates the formation of presynapses. Conclusions: By using CRISPR/cas9 technology, we have generated knockout strains of 155 C. elegans lincRNAs as valuable resources for studies in noncoding RNAs, and we provide biological insights for 23 phenotypic lincRNAs identified from 6 traits examined.
Project description:Stable and efficient guided waves are essential for information transmission and processing. Recently, topological valley-contrasting materials in condensed matter systems have been revealed as promising infrastructures for guiding classical waves, for they can provide broadband, non-dispersive and reflection-free electromagnetic/mechanical wave transport with a high degree of freedom. In this work, by designing and manufacturing miniaturized phononic crystals on a semi-infinite substrate, we experimentally realized a valley-locked edge transport for surface acoustic waves (SAWs). Critically, original one-dimensional edge transports could be extended to quasi-two-dimensional ones by doping SAW Dirac "semimetal" layers at the boundaries. We demonstrate that SAWs in the extended topological valley-locked edges are robust against bending and wavelength-scaled defects. Also, this mechanism is configurable and robust depending on the doping, offering various on-chip acoustic manipulation, e.g., SAW routing, focusing, splitting, and converging, all flexible and high-flow. This work may promote future hybrid phononic circuits for acoustic information processing, sensing, and manipulation.