The mechanism of the regulation of seed maturation by the FUS3 transcription factor revealed by transcriptome analysis

Abstract

FUS3 is one of the key transcription factors controlling seed maturation in Arabidopsis. Microarray analysis comparing the transcriptomes of developing seeds beteween the fus3 mutant and the wild type revealed altered expression of the various genes functioning in the synthesis, metabolism, transport and signal transduction of plant hormones such as auxin, gibberellins, abscisic acid and cytokinins, as well as those thought to be regulated by these plant hormones. For example, the expression of the auxin-induced genes, such as PIN7, PIN3, SUR2 and GH3 family members, were increased in the immature seeds of fus3 compared to wild type. Conversely, the expressions of some of the IAA/AUX genes were decreased in the mutant. However, no large differences in the IAA levels in the developing seeds were found between of the mutant and wild type. We will discuss about the functioning of FUS3 in seed maturation from the view point of hormonal regulation.