Division of Mechatronics, Biostatistics and Sensors (MeBioS), Department of Biosystems (BIOSYST), Katholieke Universiteit Leuven, Willem de Croylaan 42, bus 2428, B-3001, Leuven, Belgium.
Physiol Plant. 2014 Feb;150(2):161-73. doi: 10.1111/ppl.12084. Epub 2013 Sep 13.
In this study, the short-term and dynamic changes of the ethylene biosynthesis of Jonagold apple during and after application of controlled atmosphere (CA) storage conditions were quantified using a systems biology approach. Rapid responses to imposed temperature and atmospheric conditions were captured by continuous online photoacoustic ethylene measurements. Discrete destructive sampling was done to understand observed changes of ethylene biosynthesis at the transcriptional, translational and metabolic level. Application of the ethylene inhibitor 1-methylcyclopropene (1-MCP) allowed for the discrimination between ethylene-mediated changes and ethylene-independent changes related to the imposed conditions. Online ethylene measurements showed fast and slower responses during and after application of CA conditions. The changes in 1-aminocyclopropane-1-carboxylate synthase (ACS) activity were most correlated with changes in ACS1 expression and regulated the cold-induced increase in ethylene production during the early chilling phase. Transcription of ACS3 was found ethylene independent and was triggered upon warming of CA-stored apples. Increased expression of ACO1 during shelf life led to a strong increase in 1-aminocyclopropane-1-carboxylate oxidase (ACO) activity, required for the exponential production of ethylene during system 2. Expression of ACO2 and ACO3 was upregulated in 1-MCP-treated fruit showing a negative correlation with ethylene production. ACO activity never became rate limiting.
在这项研究中，采用系统生物学的方法来量化乔纳金苹果在应用受控气氛（CA）储存条件期间和之后的乙烯生物合成的短期和动态变化。通过连续的在线光声乙烯测量来捕捉对施加的温度和大气条件的快速响应。通过离散的破坏性采样来了解在转录、翻译和代谢水平上观察到的乙烯生物合成变化。应用乙烯抑制剂 1-甲基环丙烯（1-MCP）可以区分乙烯介导的变化和与施加条件相关的乙烯非依赖性变化。在线乙烯测量显示，在应用 CA 条件期间和之后，乙烯的响应速度较快和较慢。1-氨基环丙烷-1-羧酸合酶（ACS）活性的变化与 ACS1 表达的变化最相关，并调节了冷藏早期冷诱导的乙烯产生增加。ACS3 的转录被发现与乙烯无关，并且在 CA 储存苹果升温时被触发。在货架期内，ACO1 的表达增加导致 1-氨基环丙烷-1-羧酸氧化酶（ACO）活性的强烈增加，这是系统 2 中乙烯指数产生所必需的。ACO2 和 ACO3 的表达在 1-MCP 处理的果实中上调，与乙烯的产生呈负相关。ACO 活性从未成为限速步骤。
