Abstract:
Epidermal cells are the main avenue for signal and material exchange between plants and the environment. Leaf epidermal cells primarily include pavement cells, guard cells, and trichome cells. The development and distribution of different epidermal cells are tightly regulated by a complex transcriptional regulatory network mediated by phytohormones, including jasmonic acid, and transcription factors. How the fate of leaf epidermal cells is determined, however, is still largely unknown due to the diversity of cell types and the complexity of their regulation. Here, we characterized the transcriptional profiles of epidermal cells in 3-day-old true leaves of Arabidopsis thaliana using single-cell RNA sequencing. We identified two genes encoding BASIC LEUCINE-ZIPPER (bZIP) transcription factors, namely bZIP25 and bZIP53, which are highly expressed in pavement cells and early-stage meristemoid cells. Densities of pavement cells and trichome cells were found to increase and decrease, respectively, in bzip25 and bzip53 mutants, compared with wild-type plants. This trend was more pronounced in the presence of jasmonic acid, suggesting that these transcription factors regulate the development of trichome cells and pavement cells in response to jasmonic acid.
摘要:
表皮细胞是植物与环境之间信号和物质交换的主要途径。叶表皮细胞主要包括路面细胞,保卫细胞,和毛状体细胞。不同表皮细胞的发育和分布受到植物激素介导的复杂转录调控网络的严密调控,包括茉莉酸,和转录因子。叶表皮细胞的命运是如何决定的,然而,由于细胞类型的多样性及其调节的复杂性,在很大程度上仍然未知。这里,我们使用单细胞RNA测序表征了3天大的拟南芥真叶中表皮细胞的转录谱。我们确定了两个编码BASICLEUCINE-ZIPPER(bZIP)转录因子的基因,即bZIP25和bZIP53,在路面细胞和早期分生组织细胞中高度表达。发现路面细胞和毛状体细胞的密度增加和减少,分别,在bzip25和bzip53突变体中,与野生型植物相比。这种趋势在茉莉酸的存在下更为明显,提示这些转录因子响应茉莉酸调节毛状体细胞和路面细胞的发育。