The production of viable seeds is a key event in the life cycle of higher plants. Historically, abscisic acid (ABA) and gibberellin (GAs) were considered the main hormones that regulate seed formation. However, auxin has recently emerged as an essential player that modulates, in conjunction with ABA, different cellular processes involved in seed development as well as the induction, regulation and maintenance of primary dormancy (PD). This review examines and discusses the key role of auxin as a signaling molecule that coordinates seed life. The cellular machinery involved in the synthesis and transport of auxin, as well as their cellular and tissue compartmentalization, is crucial for the development of the endosperm and seed-coat. Thus, auxin is an essential compound involved in integuments development, and its transport from endosperm is regulated by AGAMOUS-LIKE62 (AGL62) whose transcript is specifically expressed in the endosperm. In addition, recent biochemical and genetic evidence supports the involvement of auxins in PD. In this process, the participation of the transcriptional regulator ABA INSENSITIVE3 (ABI3) is critical, revealing a cross-talk between auxin and ABA signaling. Future experimental aimed at advancing knowledge of the role of auxins in seed development and PD are also discussed.

中文翻译：

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生长素：种子发育和休眠所需的激素信号。

有生命力的种子的生产是高等植物生命周期中的关键事件。历史上，脱落酸（ABA）和赤霉素（GAs）被认为是调节种子形成的主要激素。然而，植物生长素最近已成为与ABA结合调节种子发育以及诱导，调节和维持原发性休眠（PD）的不同细胞过程的重要参与者。这篇评论审查并讨论了生长素作为协调种子生命的信号分子的关键作用。生长素的合成和运输以及它们在细胞和组织中的区室化涉及的细胞机制对于胚乳和种皮的发育至关重要。因此，生长素是参与外皮发展的重要化合物，并且其从胚乳的转运受AGAMOUS-LIKE62（AGL62）调控，其转录产物在胚乳中特异性表达。另外，最近的生化和遗传证据支持植物生长素参与PD。在此过程中，转录调节因子ABA INSENSITIVE3（ABI3）的参与至关重要，从而揭示了生长素和ABA信号之间的串扰。还讨论了旨在增进对植物生长素在种子发育和局部放电中作用的认识的未来实验。