Péret Benjamin, Larrieu Antoine, Bennett Malcolm J
Plant Sciences Division, School of Biosciences, University of Nottingham, Loughborough, UK.
J Exp Bot. 2009;60(13):3637-43. doi: 10.1093/jxb/erp232. Epub 2009 Jul 27.
Lateral root initiation takes place deep within the parental root, requiring new primordia to break through the overlying tissues before they emerge into the soil. Lateral root emergence has been well described at the cellular level but, until recently, the molecular mechanisms involved were unclear. Scientists in the 19th and 20th centuries hypothesized that the cell wall of the overlying tissues was modified by enzymes released by cells within the primordium. Recent studies in the model plant Arabidopsis thaliana revealed the existence of a complex transcellular signalling network regulated by auxin that controls cell wall remodelling in cells overlying lateral root primordia. In the first part of this review, early observations on the cell biology of lateral root formation and emergence are summarized, and in the following two sections recent observations in Arabidopsis that led to the identification of the molecular mechanism regulating lateral root emergence are described.
侧根起始发生在母根内部深处，需要新的原基在穿出土壤之前突破覆盖其上的组织。侧根穿出在细胞水平上已有详尽描述，但直到最近，其中涉及的分子机制仍不清楚。19世纪和20世纪的科学家们推测，覆盖组织的细胞壁会被原基内细胞释放的酶所修饰。近期对模式植物拟南芥的研究揭示，存在一个由生长素调控的复杂跨细胞信号网络，该网络控制着侧根原基上方细胞的细胞壁重塑。在本综述的第一部分，总结了关于侧根形成和穿出的细胞生物学的早期观察结果，在接下来的两节中，描述了在拟南芥中的近期观察结果，这些观察结果促成了对调控侧根穿出的分子机制的鉴定。
