比利时根特大学Bert De Rybel及Yvan Saeys课题组发现血管转录因子介导植物表皮对有限磷酸盐的反应。2020年9月17日，《科学》杂志发表了这项成果。

通过生成和利用拟南芥根部高分辨率单细胞基因表达谱数据，研究人员发现根毛细胞存在丰富的MONOPTEROS 5 / LONESOME HIGHWAY（TMO5 / LHW）靶基因反应。TMO5 / LHW异二聚体通过改变表皮细胞的长度和细胞命运，诱导血管细胞中移动细胞分裂素的生物合成，并在低磷酸盐条件下增加根毛密度。

此外,在磷酸盐缺乏的条件下，存在TMO5和细胞分裂素依赖性根毛反应。总之，细胞分裂素信号传导将根毛表皮中的反应与对血管细胞中磷酸盐消耗的感知联系起来。

据了解，植物的最适生长受到土壤中必需常量营养元素磷酸盐缺乏的影响。但是，植物根可以增加其根毛密度，从而有效地在土壤中吸取这种不可移动的养分。

附：英文原文

Title: Vascular transcription factors guide plant epidermal responses to limiting phosphate conditions

Author: Jos R. Wendrich, BaoJun Yang, Niels Vandamme, Kevin Verstaen, Wouter Smet, Celien Van de Velde, Max Minne, Brecht Wybouw, Eliana Mor, Helena E. Arents, Jonah Nolf, Julie Van Duyse, Gert Van Isterdael, Steven Maere, Yvan Saeys, Bert De Rybel

Issue&Volume: 2020/09/17

Abstract: Optimal plant growth is hampered by deficiency of the essential macronutrient phosphate in most soils. Plant roots can, however, increase their root hair density to efficiently forage the soil for this immobile nutrient. By generating and exploiting a high-resolution single-cell gene expression atlas of Arabidopsis roots, we show an enrichment of TARGET OF MONOPTEROS 5 / LONESOME HIGHWAY (TMO5/LHW) target gene responses in root hair cells. The TMO5/LHW heterodimer triggers biosynthesis of mobile cytokinin in vascular cells and increases root hair density during low phosphate conditions by modifying both the length and cell fate of epidermal cells. Moreover, root hair responses in phosphate deprived conditions are TMO5 and cytokinin dependent. In conclusion, cytokinin signaling links root hair responses in the epidermis to perception of phosphate depletion in vascular cells.

DOI: 10.1126/science.aay4970

Source: https://science.sciencemag.org/content/early/2020/09/16/science.aay4970