Huang Ling, Shi Xinhui, Wang Wenjia, Ryu Kook Hui, Schiefelbein John
Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109.
Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109
Plant Physiol. 2017 Jul;174(3):1697-1712. doi: 10.1104/pp.17.00374. Epub 2017 May 9.
The molecular genetic program for root hair development has been studied intensively in Arabidopsis (). To understand the extent to which this program might operate in other plants, we conducted a large-scale comparative analysis of root hair development genes from diverse vascular plants, including eudicots, monocots, and a lycophyte. Combining phylogenetics and transcriptomics, we discovered conservation of a core set of root hair genes across all vascular plants, which may derive from an ancient program for unidirectional cell growth coopted for root hair development during vascular plant evolution. Interestingly, we also discovered preferential diversification in the structure and expression of root hair development genes, relative to other root hair- and root-expressed genes, among these species. These differences enabled the definition of sets of genes and gene functions that were acquired or lost in specific lineages during vascular plant evolution. In particular, we found substantial divergence in the structure and expression of genes used for root hair patterning, suggesting that the Arabidopsis transcriptional regulatory mechanism is not shared by other species. To our knowledge, this study provides the first comprehensive view of gene expression in a single plant cell type across multiple species.
在拟南芥中，人们对根毛发育的分子遗传程序进行了深入研究。为了解该程序在其他植物中的运行程度，我们对多种维管植物（包括双子叶植物、单子叶植物和一种石松类植物）的根毛发育基因进行了大规模比较分析。结合系统发育学和转录组学，我们发现所有维管植物中存在一组核心根毛基因的保守性，这可能源于维管植物进化过程中为根毛发育而采用的古老单向细胞生长程序。有趣的是，我们还发现相对于这些物种中的其他根毛和根表达基因，根毛发育基因在结构和表达上存在优先多样化。这些差异使得能够定义在维管植物进化过程中特定谱系中获得或丢失的基因集和基因功能。特别是，我们发现用于根毛模式形成的基因在结构和表达上存在显著差异，这表明其他物种并不共享拟南芥的转录调控机制。据我们所知，这项研究首次全面展示了跨多个物种的单一植物细胞类型中的基因表达情况。
