植物根部圖解,，顯示了細(xì)胞和根毛分布,，植物生長素（auxin）傳輸方向用粉紅色標(biāo)明,。
（圖片來源：Claire Grierson）
面對氣候變化,，由于肥料和供水導(dǎo)致了極大的能源和環(huán)境成本,，讓作物更有效率地吸收營養(yǎng)和水從而增加產(chǎn)量顯得越發(fā)重要,。英國布里斯托大學(xué)科學(xué)家揭示了如何增加植物根毛（root hair）長度,，而具較長根毛的植物能更有效地吸收水和養(yǎng)分，從而可能提高作物產(chǎn)量。研究相關(guān)論文在線發(fā)表于12月14日的《自然—細(xì)胞生物學(xué)》（Nature Cell Biology）,。
論文第一作者,、布里斯托大學(xué)生物學(xué)博士生Angharad (Harry) Jones表示：“每根根毛都是一個(gè)單獨(dú)的伸長的細(xì)胞，其長度依賴于植物生長激素的供給程度,。難點(diǎn)在于理解植物生長素如何傳送到根毛來促進(jìn)生長,。”1880年，達(dá)爾文和他的兒子Francis第一次發(fā)現(xiàn)了植物的向光性生長,，這一發(fā)現(xiàn)最后導(dǎo)致了植物激素的發(fā)現(xiàn),。
由于無法直接觀察到植物生長素，Jones使用了由美國巴德學(xué)院（Bard College）物理學(xué)家Eric Kramer創(chuàng)建的計(jì)算機(jī)模型來計(jì)算植物生長素可能會(huì)出現(xiàn)的位置,。
模型揭示出了令人驚奇的結(jié)果,，植物生長素不是直接到達(dá)根毛細(xì)胞，而是通過旁邊的細(xì)胞作為管道來傳輸,。在傳輸過程中,，一些植物生長素發(fā)生泄露，為根毛細(xì)胞提供了令其生長的信號(hào),。這一新的見解將非常有助于農(nóng)民培育可持續(xù)性作物,，而且可降低肥料浪費(fèi)，從而避免對生態(tài)系統(tǒng)造成嚴(yán)重破壞,。
論文通訊作者、布里斯托大學(xué)的Claire Grierson補(bǔ)充說：“這一重要的新工作是‘綜合生物學(xué)’的一個(gè)例子,， 是一種創(chuàng)新的,、多學(xué)科方法，利用數(shù)學(xué)模型和計(jì)算機(jī)模擬來驗(yàn)證單靠實(shí)驗(yàn)很難或無法研究的想法,。這一方法產(chǎn)生了對生物學(xué)機(jī)理突破性和令人驚奇的理解,，而用其它方法很可能無法發(fā)現(xiàn)。”（生物谷Bioon.com）
生物谷推薦原始出處：
Nature Cell Biology,，doi:10.1038/ncb1815,，Angharad R. Jones，Claire S. Grierson
Auxin transport through non-hair cells sustains root-hair development
Angharad R. Jones1, Eric M. Kramer2,3, Kirsten Knox4,5, Ranjan Swarup3,6, Malcolm J. Bennett3,6, Colin M. Lazarus1, H. M. Ottoline Leyser4 & Claire S. Grierson1
The plant hormone auxin controls root epidermal cell development in a concentration-dependent manner1, 2, 3. Root hairs are produced on a subset of epidermal cells as they increase in distance from the root tip. Auxin is required for their initiation4, 5, 6, 7 and continued growth8, 9, 10, 11, but little is known about its distribution in this region of the root. Contrary to the expectation that hair cells might require active auxin influx to ensure auxin supply, we did not detect the auxin-influx transporter AUX1 in root-hair cells. A high level of AUX1 expression was detected in adjacent non-hair cell files. Non-hair cells were necessary to achieve wild-type root-hair length, although an auxin response was not required in these cells. Three-dimensional modelling of auxin flow in the root tip suggests that AUX1-dependent transport through non-hair cells maintains an auxin supply to developing hair cells as they increase in distance from the root tip, and sustains root-hair outgrowth. Experimental data support the hypothesis that instead of moving uniformly though the epidermal cell layer3, 12, auxin is mainly transported through canals that extend longitudinally into the tissue.
1 School of Biological Sciences, University of Bristol, BS8 1UG, UK.
2 Physics Department, Bard College at Simon's Rock, Massachusetts, MA 01230, USA.
3 Centre for Plant Integrative Biology, University of Nottingham, LE12 5RD UK.
4 Department of Biology, University of York, YO10 5YW, UK.
5 Institute of Molecular Plant Sciences, University of Edinburgh, EH9 3JR, UK.
6 Plant Sciences Division, School of Biosciences, University of Nottingham, LE12 5RD UK.
