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Plant roots show distinct gene-expression profiles from those of shoots under abiotic stress conditions. In this study, we performed mRNA sequencing (mRNA-Seq) to analyze the transcriptional profiling of Arabidopsis roots under osmotic stress conditions—high salinity (NaCl) and drought (mannitol). The roots demonstrated significantly distinct gene-expression changes from those of the aerial parts under both the NaCl and the mannitol treatment. We identified 68 closely connected transcription-factor genes involved in osmotic stress-signal transduction in roots. Well-known abscisic acid (ABA)-dependent and/or ABA-independent osmotic stress-responsive genes were not considerably upregulated in the roots compared to those in the aerial parts, indicating that the osmotic stress response in the roots may be regulated by other uncharacterized stress pathways. Moreover, we identified 26 osmotic-stress-responsive genes with distinct expressions of alternative splice variants in the roots. The quantitative reverse-transcription polymerase chain reaction further confirmed that alternative splice variants, such as those for ANNAT4, MAGL6, TRM19, and CAD9, were differentially expressed in the roots, suggesting that alternative splicing is an important regulatory mechanism in the osmotic stress response in roots. Altogether, our results suggest that tightly connected transcription-factor families, as well as alternative splicing and the resulting splice variants, are involved in the osmotic stress response in roots. [ABSTRACT FROM AUTHOR]

Plant roots show distinct gene-expression profiles from those of shoots under abiotic stress conditions. In this study, we performed mRNA sequencing (mRNA-Seq) to analyze the transcriptional profiling of Arabidopsis roots under osmotic stress conditions—high salinity (NaCl) and drought (mannitol). The roots demonstrated significantly distinct gene-expression changes from those of the aerial parts under both the NaCl and the mannitol treatment. We identified 68 closely connected transcription-factor genes involved in osmotic stress-signal transduction in roots. Well-known abscisic acid (ABA)-dependent and/or ABA-independent osmotic stress-responsive genes were not considerably upregulated in the roots compared to those in the aerial parts, indicating that the osmotic stress response in the roots may be regulated by other uncharacterized stress pathways. Moreover, we identified 26 osmotic-stress-responsive genes with distinct expressions of alternative splice variants in the roots. The quantitative reverse-transcription polymerase chain reaction further confirmed that alternative splice variants, such as those for ANNAT4, MAGL6, TRM19, and CAD9, were differentially expressed in the roots, suggesting that alternative splicing is an important regulatory mechanism in the osmotic stress response in roots. Altogether, our results suggest that tightly connected transcription-factor families, as well as alternative splicing and the resulting splice variants, are involved in the osmotic stress response in roots.

Gluconacetobacter diazotrophicus has been the focus of several studies aiming to understand the mechanisms behind this endophytic diazotrophic bacterium. The present study is the first global analysis of the early transcriptional response of exponentially growing G. diazotrophicus to iron, an essential cofactor for many enzymes involved in various metabolic pathways. RNA-seq, targeted gene mutagenesis and computational motif discovery tools were used to define the G. diazotrophicusfur regulon. The data analysis showed that genes encoding functions related to iron homeostasis were significantly upregulated in response to iron limitations. Certain genes involved in secondary metabolism were overexpressed under iron-limited conditions. In contrast, it was observed that the expression of genes involved in Fe-S cluster biosynthesis, flagellar biosynthesis and type IV secretion systems were downregulated in an iron-depleted culture medium. Our results support a model that controls transcription in G. diazotrophicus by fur function. The G. diazotrophicusfur protein was able to complement an E. colifur mutant. These results provide new insights into the effects of iron on the metabolism of G. diazotrophicus, as well as demonstrate the essentiality of this micronutrient for the main characteristics of plant growth promotion by G. diazotrophicus. [ABSTRACT FROM AUTHOR]

Gluconacetobacter diazotrophicus has been the focus of several studies aiming to understand the mechanisms behind this endophytic diazotrophic bacterium. The present study is the first global analysis of the early transcriptional response of exponentially growing G. diazotrophicus to iron, an essential cofactor for many enzymes involved in various metabolic pathways. RNA-seq, targeted gene mutagenesis and computational motif discovery tools were used to define the G. diazotrophicusfur regulon. The data analysis showed that genes encoding functions related to iron homeostasis were significantly upregulated in response to iron limitations. Certain genes involved in secondary metabolism were overexpressed under iron-limited conditions. In contrast, it was observed that the expression of genes involved in Fe-S cluster biosynthesis, flagellar biosynthesis and type IV secretion systems were downregulated in an iron-depleted culture medium. Our results support a model that controls transcription in G. diazotrophicus by fur function. The G. diazotrophicusfur protein was able to complement an E. colifur mutant. These results provide new insights into the effects of iron on the metabolism of G. diazotrophicus, as well as demonstrate the essentiality of this micronutrient for the main characteristics of plant growth promotion by G. diazotrophicus.

Naringenin, a natural flavonoid widely found in citrus fruits, has been reported to possess anti-oxidant, anti-inflammatory, and hepatoprotective properties as a natural dietary supplement. However, the regulatory mechanism of naringenin in human liver remains unclear. In the present study, messenger RNA sequencing (mRNA-seq), microRNA sequencing (miRNA-seq), and real-time qPCR were used to distinguish the expression differences between control and naringenin-treated HepaRG cells. We obtained 1037 differentially expressed mRNAs and 234 miRNAs. According to the target prediction and integration analysis in silico, we found 20 potential miRNA-mRNA pairs involved in liver metabolism. This study is the first to provide a perspective of miRNA–mRNA interactions in the regulation of naringenin via an integrated analysis of mRNA-seq and miRNA-seq in HepaRG cells, which further characterizes the nutraceutical value of naringenin as a food additive.

Notch signaling as a conserved cell fate regulator is involved in the regulation of cell quiescence, proliferation, differentiation and postnatal tissue regeneration. However, how Notch signaling regulates porcine satellite cells (PSCs) has not been elucidated. We stably transfected Notch1 intracellular domain (N1ICD) into PSCs to analyze the gene expression profile and miRNA-seq. The analysis of the gene expression profile identified 295 differentially-expressed genes (DEGs) in proliferating-N1ICD PSCs (P-N1ICD) and nine DEGs on differentiating-N1ICD PSCs (D-N1ICD), compared with that in control groups (P-Control and D-Control, respectively). Analyzing the underlying function of DEGs showed that most of the upregulated DEGs enriched in P-N1ICD PSCs are related to the cell cycle. Forty-four and 12 known differentially-expressed miRNAs (DEMs) were identified in the P-N1ICD PSCs and D-N1ICD PSCs group, respectively. Furthermore, we constructed the gene-miRNA network of the DEGs and DEMs. In P-N1ICD PSCs, miR-125a, miR-125b, miR-10a-5p, ssc-miR-214, miR-423 and miR-149 are downregulated hub miRNAs, whose corresponding hub genes are marker of proliferation Ki-67 (MKI67) and nuclear receptor binding SET domain protein 2 (WHSC1). By contrast, miR-27a, miR-146a-5p and miR-221-3p are upregulated hub miRNAs, whose hub genes are RUNX1 translocation partner 1 (RUNX1T1) and fibroblast growth factor 2 (FGF2). All the hub miRNAs and genes are associated with cell proliferation. Quantitative RT-PCR results are consistent with the gene expression profile and miRNA-seq results. The results of our study provide valuable information for understanding the molecular mechanisms underlying Notch signaling in PSCs and skeletal muscle development. [ABSTRACT FROM AUTHOR]

Notch signaling as a conserved cell fate regulator is involved in the regulation of cell quiescence, proliferation, differentiation and postnatal tissue regeneration. However, how Notch signaling regulates porcine satellite cells (PSCs) has not been elucidated. We stably transfected Notch1 intracellular domain (N1ICD) into PSCs to analyze the gene expression profile and miRNA-seq. The analysis of the gene expression profile identified 295 differentially-expressed genes (DEGs) in proliferating-N1ICD PSCs (P-N1ICD) and nine DEGs on differentiating-N1ICD PSCs (D-N1ICD), compared with that in control groups (P-Control and D-Control, respectively). Analyzing the underlying function of DEGs showed that most of the upregulated DEGs enriched in P-N1ICD PSCs are related to the cell cycle. Forty-four and 12 known differentially-expressed miRNAs (DEMs) were identified in the P-N1ICD PSCs and D-N1ICD PSCs group, respectively. Furthermore, we constructed the gene-miRNA network of the DEGs and DEMs. In P-N1ICD PSCs, miR-125a, miR-125b, miR-10a-5p, ssc-miR-214, miR-423 and miR-149 are downregulated hub miRNAs, whose corresponding hub genes are marker of proliferation Ki-67 (MKI67) and nuclear receptor binding SET domain protein 2 (WHSC1). By contrast, miR-27a, miR-146a-5p and miR-221-3p are upregulated hub miRNAs, whose hub genes are RUNX1 translocation partner 1 (RUNX1T1) and fibroblast growth factor 2 (FGF2). All the hub miRNAs and genes are associated with cell proliferation. Quantitative RT-PCR results are consistent with the gene expression profile and miRNA-seq results. The results of our study provide valuable information for understanding the molecular mechanisms underlying Notch signaling in PSCs and skeletal muscle development.

Naringenin, a natural flavonoid widely found in citrus fruits, has been reported to possess anti-oxidant, anti-inflammatory, and hepatoprotective properties as a natural dietary supplement. However, the regulatory mechanism of naringenin in human liver remains unclear. In the present study, messenger RNA sequencing (mRNA-seq), microRNA sequencing (miRNA-seq), and real-time qPCR were used to distinguish the expression differences between control and naringenin-treated HepaRG cells. We obtained 1037 differentially expressed mRNAs and 234 miRNAs. According to the target prediction and integration analysis in silico, we found 20 potential miRNA-mRNA pairs involved in liver metabolism. This study is the first to provide a perspective of miRNA–mRNA interactions in the regulation of naringenin via an integrated analysis of mRNA-seq and miRNA-seq in HepaRG cells, which further characterizes the nutraceutical value of naringenin as a food additive. [ABSTRACT FROM AUTHOR]