Abstract：
The coloration of the apple fruit (Malus × domestica Borkh.) depends on pigment content. Light stimulus activates a broad range of photosynthesis-related genes, including carotenoids. The effect of light on two red commercial apple cultivars, \'Summer Prince\' and \'Arisoo\' at the juvenile stage were examined. Apple fruits were either bagged to reduce light irradiation or were exposed to direct, enhanced sunlight (reflected). The pigment content and the expression of carotenoid metabolism genes in the peel and flesh of apple fruits were significantly different between the shaded and the reflected parts. These parameters were also different in the two cultivars, highlighting the contribution of the genetic background. Further, a combination of light and transient overexpression of carotenogenic genes increased fruit coloration and pigment content in the variety \'RubyS\'. Western blot analysis showed the expression of small heat shock proteins (smHSP) in lysates extracted from the reflected part of the fruits but not in the bagged fruits, indicating the activation of smHSP in response to heat generated by the reflected light. Therefore, the synergy between the genes and the environment dictates the color of apple fruits.
摘要：
苹果果实的颜色（Malus×domesticaBorkh。)取决于颜料含量。光刺激激活广泛的光合作用相关基因，包括类胡萝卜素.光照对两个红色商业苹果品种的影响，检查了少年阶段的\'夏季王子\'和\'Arisoo\'。苹果水果要么装袋以减少光照，要么直接暴露在阳光下，增强阳光（反射）。苹果果实果皮和果肉中色素含量和类胡萝卜素代谢基因的表达在阴影部分和反射部分之间差异显著。这些参数在两个品种中也不同，强调遗传背景的贡献。Further,光和瞬时过表达类胡萝卜素基因的组合增加了品种“RubyS”的果实颜色和色素含量。Westernblot分析显示小热休克蛋白（smHSP）在从果实反射部分提取的裂解物中表达，但在袋装果实中未表达，指示响应于由反射光产生的热的smHSP的激活。因此,基因和环境之间的协同作用决定了苹果果实的颜色。
