Signalling between the shoot apical meristem and developing lateral organs
Signalling between the shoot apical meristem and developing lateral organs
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DOI：
10.1007/s11103-005-1270-y
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发表时间：
2006-04-01
影响因子：
5.1
通讯作者：
Golz, John F.
中科院分区：
文献类型：
--
作者：
Golz, John F.
植物发育的一个特征是细胞间信号在调节生长模式和细胞命运中发挥的广泛作用。这在茎尖分生组织（SAM）中特别明显，其中信号传导参与维持中央未分化干细胞群体以及从分生组织外围形成规则且可预测的叶图案。虽然这两种功能发生在分生组织的不同区域，但它们的活动必须协调以维持分生组织的完整性。信号在SAM中的作用在60多年前首次通过优雅的手术实验进行了表征。这些研究表明，现有的叶原基决定未来的网站的器官形成在相邻地区的SAM，这一发现奠定了基础，为后续研究的机制控制叶序。最近的研究已经确定生长素作为一个可能的信号促进器官的形成，并表明，年轻的原基在决定其在SAM的分布发挥重要作用。这些开创性的外科实验还揭示了来自分生组织的信号调节器官原基的发育。在这种情况下，分生组织信号促进在新兴叶的顶部/近轴半中发现的细胞类型的形成。虽然这个信号的身份仍然难以捉摸，最近表征的一个小家庭的PHABULOSA样（PHB-like）转录因子基因提供了重要的线索，其性质。这些基因，促进近轴细胞的身份，是由microRNAs（miRNA）提高了令人兴奋的可能性，分生组织信号是一个miRNA或一个途径的一部分，调节miRNA的分布。
A characteristic feature of plant development is the extensive role played by cell-cell signalling in regulating patterns of growth and cell fate. This is particularly apparent in the shoot apical meristem (SAM) where signalling is involved in the maintenance of a central undifferentiated stem cell population and the formation of a regular and predictable pattern of leaves, from the meristem periphery. Although these two functions occur in different regions of the meristem, their activity must be coordinated to maintain meristem integrity. The role of signalling in the SAM was first characterised over 60 years ago by elegant surgical experiments. These studies showed that existing leaf primordia determine future sites of organ formation in adjacent regions of the SAM, a finding that laid the foundation for subsequent studies into the mechanisms controlling phyllotaxy. Recent studies have identified auxin as a likely signal promoting organ formation and shown that young primordia play an important role in determining its distribution in the SAM. These pioneering surgical experiments also revealed that signals from the meristem regulate the development of organ primordia. In this case a meristem signal promotes the formation of cell types found in the top/adaxial half of the emerging leaf. While the identity of this signal remains elusive, the recent characterisation of a small family of PHABULOSA-like (PHB-like) transcription factor genes has provided important clues to its nature. These genes, which promote adaxial cell identity, are regulated by microRNAs (miRNAs) raising the exciting possibility that the meristem signal is either a miRNA or part of a pathway regulating the distribution of miRNAs.