Contrasting Transcriptional Programs Control Postharvest Development of Apples (<i>Malus x domestica</i> Borkh.) Submitted to Cold Storage and Ethylene Blockage

Apple is commercially important worldwide. Favorable genomic contexts and postharvest technologies allow year-round availability. Although ripening is considered a unidirectional developmental process toward senescence, storage at low temperatures, alone or in combination with ethylene blockage, is effective in preserving apple properties. Quality traits and genome wide expression were integrated to investigate the mechanisms underlying postharvest changes. Development and conservation techniques were responsible for transcriptional reprogramming and distinct programs associated with quality traits. A large portion of the differentially regulated genes constitutes a program involved in ripening and senescence, whereas a smaller module consists of genes associated with reestablishment and maintenance of juvenile traits after harvest. Ethylene inhibition was associated with a reversal of ripening by transcriptional induction of anabolic pathways. Our results demonstrate that the blockage of ethylene perception and signaling leads to upregulation of genes in anabolic pathways. We also associated complex phenotypes to subsets of differentially regulated genes.苹果在全球范围内具有重要的商业价值。优良的基因组背景与采后技术使得苹果可全年供应。尽管果实成熟（ripening）被认为是指向衰老（senescence）的单向发育过程，但单独或配合使用乙烯（ethylene）阻断处理的低温贮藏，可有效维持苹果的品质特性。本研究整合了品质性状与全基因组表达数据，以解析采后变化的潜在分子机制。发育调控与保鲜技术可引发转录重编程（transcriptional reprogramming），以及与品质性状相关的独特表达程序。大部分差异调控基因（differentially regulated genes）参与成熟与衰老相关的表达程序，而较小的基因模块则与采后幼态性状的重建与维持相关。乙烯抑制可通过诱导合成代谢通路（anabolic pathways）的转录，实现果实成熟的逆转。本研究结果表明，阻断乙烯感知与信号转导可上调合成代谢通路中的基因表达；同时，我们将复杂表型与特定的差异调控基因子集建立了关联。