College of Forestry, Beijing Forestry University, Beijing 100083, China.
Physiol Plant. 2011 Aug;142(4):390-406. doi: 10.1111/j.1399-3054.2011.01479.x. Epub 2011 Jun 8.
The development of the stone and formation of peach (Prunus persica) fruit were explored in this work using a proteomic approach. Sixty-eight proteins with different expression patterns were identified in both the endocarp and mesocarp during early fruit development (from 28 to 59 days after flowering) and the majority were involved in primary or secondary metabolism. In contrast to most proteins associated with primary metabolism in the endocarp, whose expression is down-regulated, expression of pyruvate dehydrogenase (PDH) unexpectedly increased exponentially. Moreover, its expression pattern was linearly positively correlated with the exponentially growing lignin content (R = 0.940), which suggests that PDH may play a role in endocarp lignification. Our data also revealed different spatiotemporal expressions of enzymes involved in the lignin and flavonoid pathways that provided proteome-level evidence to support the hypothesis that these two pathways are competitive during endocarp development. In addition, we observed endocarp-specific oxidative stress and propose that it may act as a stimulating factor in activating lignification and subsequent programmed cell death in the endocarp.
本研究采用蛋白质组学方法探讨了桃果实石细胞和肉质果的发育过程。在早期果实发育（花后 28 至 59 天）过程中，从内果皮和中果皮中鉴定出 68 种表达模式不同的蛋白质，其中大多数与初级或次级代谢有关。与内果皮中大多数与初级代谢相关的蛋白质表达下调不同，丙酮酸脱氢酶（PDH）的表达出乎意料地呈指数增长。此外，其表达模式与木质素含量的指数增长呈线性正相关（R = 0.940），这表明 PDH 可能在内果皮木质化过程中发挥作用。我们的数据还揭示了木质素和类黄酮途径中参与酶的不同时空表达，为这两个途径在发育过程中存在竞争的假说提供了蛋白质组水平的证据。此外，我们观察到内果皮特异性氧化应激，并提出它可能作为激活木质化和随后内果皮程序性细胞死亡的刺激因素。
