背景回顾：Male and female unisexual flowers evolved from hermaphroditic ancestors, and control of flower sex is useful for plant breeding.  

主要发现：We isolated a female-to-male sex transition mutant in melon and identified the causal gene as the carpel identity gene CRABS CLAW (CRC). 

结果1-WIP1抑制CRC表达：We show that the master regulator of sex determination in cucurbits, the transcription factor WIP1 whose expression orchestrates male flower development, recruits the corepressor TOPLESS to the CRC promoter to suppress its expression through histone deacetylation. 

结果2-CRC表达作用于雌花发育：Impairing TOPLESS-WIP1 physical interaction leads to CRC expression, carpel determination, and consequently the expression of the stamina inhibitor, the aminocyclopropane-1-carboxylic acid synthase 7 (CmACS7), leading to female flower development.  

结论：Our findings suggest that sex genes evolved to interfere with flower meristematic function, leading to unisexual flower development. 

单性花是由雌雄同花的祖先演化而来，植物花性别的控制在植物育种领域具有很强的实际应用价值。本文中，作者在甜瓜中分离出了一个雌花向雄花转变的突变体，并且发现心皮特征基因CRC是这一突变体的突变基因。葫芦科植物性别决定核心调控因子WIP1的表达作用于雄花的发育，作者发现该基因能够招募辅阻遏子TOPLESS至CRC基因的启动子上，通过组蛋白去乙酰化抑制CRC基因的表达。TOPLESS-WIP1互作缺陷会导致CRC基因的表达、心皮决定以及雄蕊抑制子CmACS7的组成型表达，从而导致雌花的发育。本文的研究表明植物性别决定基因演化出干扰了花分生组织的功能，从而演化出单性花发育。