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Ashida, A.

Publications and source records attributed to Ashida, A..

2 recordsLinked to original sources
bioRxiv2021

AP2/ERF transcription factor NbERF-IX-33 is involved in the regulation of phytoalexin production for the resistance of Nicotiana benthamiana to Phytophthora infestans.

Plants recognize molecular patterns unique to a certain group of microbes to induce effective resistance mechanisms. Elicitins are secretory proteins produced by plant pathogenic oomycete genera including Phytophthora and Pythium. Treatment of INF1 (an elicitin produced by P. infestans) induces a series of defense responses in Nicotiana species, including reactive oxygen species (ROS) production, transient induction of ethylene production, hypersensitive cell death and accumulation of the sesquiterpenoid phytoalexin capsidiol. In this study, we analyzed the expression profiles of N. benthamiana genes after INF1 treatment by RNAseq analysis. Based on their expression patterns, N. benthamiana genes were categorized into 20 clusters and 4,761 (8.3%) out of 57,140 genes were assigned to the clusters for INF1-induced genes. All genes encoding enzymes dedicated to capsidiol production, 5-epi-aristolochene (EA) synthase (NbEAS, 10 copies) and EA dehydrogenase (NbEAH, 6 copies), and some genes for ethylene production, such as 1-aminocyclopropane 1-carboxylate (ACC) synthase (NbACS) and ACC oxidase (NbACO), were significantly upregulated by INF1 treatment. Analysis of NbEAS1 and NbEAS4 promoters revealed that AGACGCC (GCC box-like motif) is the essential cis-element required for INF1-induced expression of NbEAS genes. Given that the GCC box is known to be targeted by ERF (ethylene-responsive factor) transcription factors, we created a complete list of N. benthamiana genes encoding AP2/ERF family transcription factors, and identified 45 out of 337 AP2/ERF genes in the clusters for INF1-induced genes. Among INF1-induced NbERF genes, silencing of NbERF-IX-33 compromised resistance against P. infestans and INF1-induced production of capsidiol. Recombinant NbERF-IX-33 protein can bind to the promoter sequence of NbEAS4, suggesting that NbERF-IX-33 is a transcription factor directly regulating the expression of genes for phytoalexin production.

plant biology↗
bioRxiv2021

A selective glucocorticoid receptor modulator attenuates lung inflammation and improves alveolarization in a neonatal rat model of bronchopulmonary dysplasia.

BackgroundBronchopulmonary dysplasia (BPD) is a major problem for extremely preterm infants. Glucocorticoids effectively treat BPD; however, they have many side effects. Compound A (Cpd A) is a nonsteroidal Selective Glucocorticoid Receptor Modulator (SEGRM) that acts as a glucocorticoid receptor ligand without inducing the expression of glucocorticoid-response element-driven genes. Cpd A reportedly has anti-inflammatory properties with fewer side effects than glucocorticoids. MethodsUsing a bleomycin (Bleo)-induced BPD model, we evaluated the therapeutic effects of Cpd A. 0-day-old Sprague-Dawley rats were administered Bleo for 10 days and treated with dexamethasone (Dex) or Cpd A from day 0 to 13. We evaluated lung pathology by histology and the mRNA levels of interleukin (IL)-1{beta}, transforming growth factor (TGF)-{beta}1 and chemokines, CXCL1 and CCL2. ResultsBleo-treated mice had lungs with impaired alveolarization. Dex and Cpd A treatments improved the alveolar structure, attenuating the lung injury. Bleo-exposed lungs had increased inflammatory cells recruitment and inflammatory mediator mRNA levels. Cpd A treatment reduced inflammatory cells infiltration and CXCL1, CCL2 and TGF-{beta}1 expression. ConclusionCpd A improved lung inflammation and alveolar maturation arrest, and restored histological and biochemical changes in a model of BPD. SEGRMs, including Cpd A, are promising candidates for the therapy of BPD. Impact Statement{circ} What is the key message of your article? Compound A decreased lung inflammation and improved lung morphometric changes in Bleomycin-exposed lungs. {circ}What does it add to the existing literature? Compound A has anti-inflammatory effects in an experimental model of BPD. {circ}What is the impact? SEGRMs, including Cpd A, may be promising candidates for the therapy of BPD.

pathology↗