PNAS∣乙烯促進根毛生長新機制--南方科技大與北大合作文章

02-03

2017年12月12日PNAS在線文章，該文章為南方科技大學講座教授郭紅衛課題組發表，第一作者單位為南方科技大學和北京大學。文章講述了EIN3/EIL1和RHD6/RSL1組成的關鍵轉錄複合體，在根毛髮生和伸長的控制中起著重要的作用。

原題目為：

Ethylene promotes root hair growth through coordinated EIN3/EIL1 and RHD6/RSL1 activity in Arabidopsis

意義：

根毛是根表皮細胞的單細胞延伸，幫助植物增加水分和養分吸收，改善土壤固著，這兩方面對全球公認的降低化肥用量，提高作物產量的目標都是至關重要的。以前的研究，在控制根毛髮育中已經涉及到許多基因和植物激素。本研究揭示了乙烯促進根毛生長的分子機制，並鑒定出一個由EIN3/EIL1和RHD6/RSL1組成的轉錄複合體，是根毛起始和伸長的關鍵調節因子。由於乙烯介導各種根毛刺激的作用，這項工作也闡明了融合多種環境因素和內在信號調控植物器官發育的融合信號網路。

Significance

Root hairs are unicellular extensions of root epidermal cells that help plants increase water and nutrient uptake and improve soil anchorage, both of which are crucial for the globally recognized goal of yield improvement with reduced fertilizer use. Previous studies have implicated numerous genes and phytohormones in the control of root hair development. This work uncovers the molecular mechanism of ethylene (ET)-promoted root hair growth and identifies a transcriptional complex consisting of EIN3/EIL1 and RHD6/RSL1 as the key regulator of root hair initiation and elongation. As ET mediates the effects of various root hair stimuli, this work also elucidates a convergent signaling network that integrates diverse environmental cues and intrinsic signals to modulate plant organ development.

摘要：

根毛是根表皮細胞的廣泛結構，對於固著的植物來說，它對營養吸收，土壤固著和環境相互作用有重要作用。植物激素乙烯促進根毛生長，並且還具有介導刺激根毛細胞發育的不同信號的作用。然而，乙烯誘導的根毛生長的分子基礎仍然知之甚少。在這裡，我們研究顯示， EIN3與一個已被研究的根毛細胞正調節子RHD6可以物理上的相互作用，這兩個因子可以直接的共激活根毛長度決定基因RSL4，從而促進根毛伸長。轉錄組分析進一步揭示了調節對EIN3/EIL1和RHD6/RSL1的平行作用。EIN3/EIL1和RHD6/RSL1通過選擇性的調節一些核心根毛基因，從而協調地增強根毛髮起始。因此，本研究揭示了一個由EIN3/EIL1和RHD6/RSL1組成的關鍵轉錄複合體，在根毛髮生和伸長的控制中起著重要的作用，並為環境信號和內在調節因子在植物器官發育調控中的整合，提供了分子框架。

Abstract：

Root hairs are an extensive structure of root epidermal cells and are critical for nutrient acquisition, soil anchorage, and environmental interactions in sessile plants. The phytohormone ethylene (ET) promotes root hair growth and also mediates the effects of different signals that stimulate hair cell development. However, the molecular basis of ET-induced root hair growth remains poorly understood. Here, we show that ET-activated transcription factor ETHYLENE-INSENSITIVE 3 (EIN3) physically interacts with ROOT HAIR DEFECTIVE 6 (RHD6), a well-documented positive regulator of hair cells, and that the two factors directly coactivate the hair length-determining gene RHD6-LIKE 4 (RSL4) to promote root hair elongation. Transcriptome analysis further revealed the parallel roles of the regulator pairs EIN3/EIL1 (EIN3-LIKE 1) and RHD6/RSL1 (RHD6-LIKE 1). EIN3/EIL1 and RHD6/RSL1 coordinately enhance root hair initiation by selectively regulating a subset of core root hair genes. Thus, our work reveals a key transcriptional complex consisting of EIN3/EIL1 and RHD6/RSL1 in the control of root hair initiation and elongation, and provides a molecular framework for the integration of environmental signals and intrinsic regulators in modulating plant organ development.

每日一詞
unicellular
英[?ju:n??selj?l?(r)]
美[?jun??s?lj?l?]

adj. 單細胞的;