1] Biology Department, Center for Genomics and Systems Biology, New York University, New York, NY, USA [2] Department of Cell and Developmental Biology, UCSD, La Jolla, CA, USA.
Mol Syst Biol. 2013;9:688. doi: 10.1038/msb.2013.40.
In plants, changes in local auxin concentrations can trigger a range of developmental processes as distinct tissues respond differently to the same auxin stimulus. However, little is known about how auxin is interpreted by individual cell types. We performed a transcriptomic analysis of responses to auxin within four distinct tissues of the Arabidopsis thaliana root and demonstrate that different cell types show competence for discrete responses. The majority of auxin-responsive genes displayed a spatial bias in their induction or repression. The novel data set was used to examine how auxin influences tissue-specific transcriptional regulation of cell-identity markers. Additionally, the data were used in combination with spatial expression maps of the root to plot a transcriptomic auxin-response gradient across the apical and basal meristem. The readout revealed a strong correlation for thousands of genes between the relative response to auxin and expression along the longitudinal axis of the root. This data set and comparative analysis provide a transcriptome-level spatial breakdown of the response to auxin within an organ where this hormone mediates many aspects of development.
在植物中，局部生长素浓度的变化可以引发一系列不同的发育过程，因为不同组织对相同的生长素刺激会有不同的反应。然而，人们对生长素如何被单个细胞类型所解读知之甚少。我们对拟南芥根的四个不同组织对生长素的反应进行了转录组分析，结果表明不同的细胞类型对离散的反应具有能力。大多数生长素反应基因的诱导或抑制都表现出空间偏向性。这个新的数据集被用来研究生长素如何影响细胞身份标记物的组织特异性转录调控。此外，还将数据与根的空间表达图谱结合使用，在根尖和基部分化区域绘制了一个转录组生长素反应梯度。结果显示，在激素调节发育多个方面的器官中，数千个基因的相对生长素反应与根的纵向轴上的表达之间存在很强的相关性。这个数据集和比较分析提供了一个器官内对生长素反应的转录组水平的空间细分，其中这种激素调节着发育的许多方面。
