著者
板井 章浩 新田 順子
出版者
植物化学調節学会
雑誌
植物化学調節学会研究発表記録集 (ISSN:09191887)
巻号頁・発行日
no.44, 2009-10-06

There is a large cultivar difference in ethylene synthesis during fruit ripening in Japanese pear. Fruit storage potential is closely related to maximum level of ethylene production in Japanese pear. PPACS2 was specifically expressed in cultivars showing moderate ethylene production. We have found that PpACS2 expression can be controlled by regions comprising purine-rich (GAGA repeats) sites that are located near TATA box. PpACS2 promoter of moderate ethylene producers has either (GA)_<14> or (GA)_<10>. On the other hand, that of low ethylene producers has only (GA)_5. Recently, genes have been identified that encode a class of proteins (GABP) that binds GA-rich elements in three plant species. To identify factors that interact with the promoter regions of PpACS2, southwestern screening and 5' and 3' RACE methods following RT-PCR with degenerate primers were performed. We cloned two possible GABPs (PpRTF1 and PpGABP2) and studied their expression during fruit development and ripening. To test whether both genes are able to bind to GA repeats, eletcromobility shift assays (EMSAs) were performed. PpRTF1 protein has shown to bind (GA)_<14>, but PpGABP2 has not. Furthermore, PpRTF1 protein has the ability to bind nucleotides consisting of (GA)_<10>, but no binding activity of nucleotides consisting of (GA)_5. These results suggest that PpRTF1 protein can be involved in the regulation of PpACS2 expression.