All the above-ground organs of a plant are derived from stem cells that reside in shoot apical meristems (SAM). Over the past 25 years, the genetic pathways that control the proliferation of stem cells within the SAM, and the differentiation of their progenitors into lateral organs, have been described in great detail. However, longstanding questions regarding the importance of communication between cells within the SAM and lateral organs have, until recently, remained unanswered. In this review, we describe recent investigations into the extent, nature and significance of signaling both to and from the SAM.

中文翻译：

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孤独在高处？内、外因素对茎尖分生组织活性的调控

植物的所有地上器官都来自位于茎尖分生组织 (SAM) 中的干细胞。在过去的 25 年中，已经非常详细地描述了控制 SAM 内干细胞增殖及其祖细胞分化为侧向器官的遗传途径。然而，直到最近，关于 SAM 和侧器官内细胞之间通讯重要性的长期问题仍未得到解答。在这篇综述中，我们描述了最近对传入和传出 SAM 的信号的程度、性质和重要性的调查。