Oryza sativa Transcriptome or Gene expression. Oryza sativa

The plant hormone jasmonate (JA) plays important roles in the regulation of defense responses in many plants. To clarify the response to JA in rice at gene expression level, we performed a microarray analysis using the Agilent Rice Oligo Microarray (44k, custom-made; Agilent Technologies, Redwood City, CA, USA). As a result, treatment of JA caused high upregulation of many defense-related genes including pathogenesis-related (PR) genes in rice. However, many of these defense-related genes were not upregulated in JA-insensitive transgenic rice plant overexpressing JAZ8deltaC. Overall design: An Agilent Rice Oligo Microarray (44k, custom-made; Agilent Technologies, Redwood City, CA, USA) was used for the microarray analysis. Total RNA was extracted from leaf blades of four-leaf stage rice plants that had been treated with 100 μM JA for 1 day. For each biological replicate, material from at least three rice plants was pooled to provide a single sample for RNA extraction. We performed 4 biological replicates for each treatment. All microarray procedures and data analyses were performed according to the manufacturer’s instructions. RNA integrity was checked using an Agilent 2100 Bioanalyzer (Agilent Technologies, Redwood City, CA, USA). Total RNA (100 ng) was labeled with Cy-3 using an Agilent Low Input Quick Amp Labeling Kit, One-Color (Agilent Technologies). Fluorescently labeled targets were hybridized to Agilent Rice Oligo Microarrays for 17 h at 65°C. After hybridization, following wash processes were performed according to the manufacturer’s instructions, and hybridized microarrays were scanned using an Agilent Microarray Scanner (G2565CA; Agilent Technologies). Feature extraction software (Agilent Feature Extraction; Agilent Technologies) was used to delineate and measure the signal intensity of each spot in the array, and to normalize intensities. The background was measured around each spot as local background, calculated by the Feature Extraction software. Statistical data extraction processes were performed according to the manufacturer’s instructions.