Matilla Angel J
Department of Functional Biology, Life Campus, Faculty of Pharmacy, University of Santiago de Compostela (USC), 15782 Santiago de Compostela, Spain.
Plants (Basel). 2020 Oct 21;9(10):1402. doi: 10.3390/plants9101402.
A set of seed dormancy traits is included in this Special Issue. Thus, DELAY OF GERMINATION1 (DOG1) is reviewed in depth. Binding of DOG1 to Protein Phosphatase 2C ABSCISIC ACID (PP2C ABA) Hypersensitive Germination (AHG1) and heme are independent processes, but both are essential for DOG1's function in vivo. AHG1 and DOG1 constitute a regulatory system for dormancy and germination. DOG1 affects the ABA INSENSITIVE5 (ABI5) expression level. Moreover, reactive oxygen species (ROS) homeostasis is linked with seed after-ripening (AR) process and the oxidation of a portion of seed long-lived (SLL) mRNAs seems to be related to dormancy release. The association of SLL mRNAs to monosomes is required for their transcriptional upregulation at the beginning of germination. Global DNA methylation levels remain stable during dormancy, decreasing when germination occurs. The remarkable intervention of auxin in the life of the seed is increasingly evident year after year. Here, its synergistic cooperation with ABA to promote the dormancy process is extensively reviewed. ABI3 participation in this process is critical. New data on the effect of alternating temperatures (ATs) on dormancy release are contained in this Special Issue. On the one hand, the transcriptome patterns stimulated at ATs comprised ethylene and ROS signaling and metabolism together with ABA degradation. On the other hand, a higher physical dormancy release was observed in under 35/15 °C than under 25/15 °C, and genome-wide association analysis identified 136 candidate genes related to secondary metabolite synthesis, hormone regulation, and modification of the cell wall. Finally, it is suggested that changes in endogenous γ-aminobutyric acid (GABA) may prevent chestnut germination, and a possible relation with HO production is considered.
本期特刊包含了一系列种子休眠特性。因此，对延迟发芽1（DOG1）进行了深入综述。DOG1与蛋白磷酸酶2C脱落酸（PP2C ABA）超敏发芽（AHG1）和血红素的结合是独立的过程，但两者对于DOG1在体内的功能都是必不可少的。AHG1和DOG1构成了一个休眠和发芽的调控系统。DOG1影响脱落酸不敏感5（ABI5）的表达水平。此外，活性氧（ROS）稳态与种子后熟（AR）过程相关，种子长寿命（SLL）mRNA的一部分氧化似乎与休眠解除有关。SLL mRNA与单体的结合是其在发芽开始时转录上调所必需的。在休眠期间，全基因组DNA甲基化水平保持稳定，发芽时则降低。生长素在种子生命中的显著干预逐年变得越来越明显。在此，对其与脱落酸协同促进休眠过程进行了广泛综述。ABI3参与这一过程至关重要。本期特刊包含了关于交替温度（ATs）对休眠解除影响的新数据。一方面，ATs刺激的转录组模式包括乙烯和ROS信号传导与代谢以及脱落酸降解。另一方面，观察到在35/15°C下比在25/15°C下有更高的物理休眠解除率，全基因组关联分析确定了136个与次生代谢物合成、激素调节和细胞壁修饰相关的候选基因。最后，有人提出内源性γ-氨基丁酸（GABA）的变化可能会阻止板栗发芽，并考虑了其与HO产生的可能关系。
