Abstract
Our previous works showed that cell division started at 3 days after cutting, and auxin was essential for the induction of cell division in Arabidopsis cut flowering stems. Microarray analysis revealed that the genes related to phytohormone and transcription factor (TF) were up-regulated at earlier stage in reunion process. We examined the relationship between the gene expression and auxin, and showed that a NAC type TF was induced by auxin, while an AP2 type TF was suppressed. mIAA-transgenic plants, in which auxin response was suppressed, showed lower efficiency in cell division in reunion process, and the expression pattern of AP2 and NAC-TFs in mIAA was different from WT. The expression of genes related to ethylene and jasmonic acid synthesis were found to be up-regulated in reunion process, and it was suggested that AP2-TF was controlled by those two hormones. The transgenic plants, in which the function of AP2 or NAC-TF was suppressed showed defects in cell division in reunion process, suggesting that auxin, ethylene and jasmonic acid signalings regulate the expression of TFs that are necessary for cell division in reunion process of Arabidopsis cut flowering stems.
