Roles of cysteine proteinase genes in wilting of balloon flower petals

以桔梗（Platycodongrandiflorus）花瓣为材料，研究了4个不同的半胱氨酸蛋白酶基因在桔梗花瓣快速萎蔫过程中的作用。PgCP 1的表达上调后，花开放阶段和表达一直保持到发病萎蔫。另一方面，从萎蔫前的花瓣中新鉴定出的PgCP 3、PgCP 4和PgCP 5从萎蔫前和萎蔫期开始显著上调。启动子分析表明，PgCP1、PgCP4和PgCP5在花瓣中的表达可能是通过乙烯反应调控元件（ERE）进行调控的，而PgCP3的表达可能还受到其他未知因子的调控。

Involvement of four different genes encoding cysteine proteinase in the rapid wilting of balloon flower (Platycodon grandiflorus) petals was investigated. Expression of PgCP1 was up-regulated just after the flower opening stage and the expression remained until the onset of wilting. On the other hand, PgCP3, PgCP4 and PgCP5, which were newly identified from petals at the stage just before wilting, were markedly up-regulated from the stage just before wilting and the wilting stage. The promoter analysis indicated the possibility that the regulation via ethylene-responsive regulatory element (ERE) is involved in the expression of PgCP1, PgCP4 and PgCP5 in the petals whereas other unknown factors might be involved in regulation of PgCP3.