Spatial-temporal analysis of polyethylene glycol-reduced aluminium accumulation and xyloglucan endotransglucosylase action in root tips of common bean (Phaseolus vulgaris)
Spatial-temporal analysis of polyethylene glycol-reduced aluminium accumulation and xyloglucan endotransglucosylase action in root tips of common bean (Phaseolus vulgaris)
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聚乙二醇减少菜豆根尖铝积累和木葡聚糖内转葡糖基酶作用的时空分析
DOI：
10.1093/aob/mcw062
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发表时间：
2016
期刊：
影响因子：
4.2
通讯作者：
Yang Zhong-Bao
中科院分区：
文献类型：
--
作者：
Zhang Maolin;Ma Yanqi;Horst Walter J.;Yang Zhong-Bao
铝毒和干旱是热带酸性土壤上菜豆生产的两个主要限制因子。聚乙二醇（PEG 6000）诱导的渗透胁迫（OS）模拟干旱胁迫，可通过改变细胞壁孔隙度来降低菜豆根尖铝的积累，这可能与编码木葡聚糖内切转葡糖基酶/水解酶的两个基因PvXTH 9和PvXTHb有关。本研究的目的是了解这两个XTH基因在PEG介导的根尖铝积累中的时空调控。在PEG-2000处理下，分析了XTH基因表达和根尖中的木葡聚糖内转葡萄糖基酶（XET）的作用。通过定量逆转录-聚合酶链反应（qRT-PCR）和XET原位荧光检测等生理学和分子生物学方法，OS胁迫下，在0-2、2-7和7-12 mm的根尖区，XTH基因的表达和XET的作用明显降低，这表明XTH基因和XET酶在这些区域的CW Al积累中具有潜在的调节作用。这将有助于缓解铝和干旱胁迫，严重限制了酸性土壤上的作物产量。
Background and AimsAluminium (Al) toxicity and drought are two major limiting factors for common bean (Phaseolus vulgaris) production on tropical acid soils. Polyethylene glycol (PEG 6000)-induced osmotic stress (OS) simulating drought stress reduces Al accumulation in the entire root tips of common bean by alteration of cell-wall (CW) porosity, which might be regulated by two genes encoding xyloglucan endotransglucosylase/hydrolase,PvXTH9andPvXTHb. The aim of this research was to understand the spatial and temporal regulation of bothXTHgenes in PEG-mediated Al accumulation in the root tips.MethodsIn this study the spatial and temporal expression patterns of Al-inhibited root elongation, Al accumulation,XTHgene expression and xyloglucan endotransglucosylase (XET) enzyme action in the root tips were analysed under PEG-induced OS by a combination of physiological and molecular approaches such as quantitative reverse transcription-polymerase chain reaction (qRT-PCR) andin situfluorescence detection of XET in root tips.Key ResultsThe results showed that Al accumulation, expression ofXTHgenes and XET action were distinctly reduced in the apical 0–2, 2–7 and 7–12 mm zones under OS, implying a potential regulatory role ofXTHgenes and XET enzyme in CW Al accumulation in these zones.ConclusionsThe results provide novel insights into the physiological and molecular mechanisms of CW structure modification as a response of plant roots to OS, which will contribute to mitigate Al and drought stresses, severely limiting crop yields on acid soils.