Transcriptome analysis of floret opening and closure both Indica and Japonica rice

Floret opening and closure are critical for rice to complete reproductive development. To further understand the molecular mechanism of floret opening and closure in rice, RNA-seq was performed on the floret of Indica and Japonica rice in the state of 1-h before floret opening, at the opening and closure, respectively. Our results show that many differentially expressed genes are produced throughout the floret opening and closure of both Indica and Japonica rice. Differentially expressed genes shared between Indica and Japonica rice at floret opening were involved in seven metabolic pathways, including plant hormone signal transduction, MAPK signaling pathway-plant, starch and sucrose metabolism, alpha-Linolenic acid metabolism, plant-pathogen interaction, diterpenoid biosynthesis, glucuronate interconversions, phenylpropanoid biosynthesis, compared to 1 h before floret opening. In addition, the expression patterns of some genes, OsJAZ13, OsJAZ11 and OsCML1 which the above metabolic pathways, were different between Indica and Japonica rice. Compared to the floret opening, the differentially expressed genes at floret closure were mainly involved in the following three metabolic pathways: Circadian rhythm-plant, sesquiterpenoid and triterpenoid biosynthesis, starch and sucrose metabolism, and thiamine metabolism. This study provides insights into revealing the molecular mechanism of floret opening and closure in rice.