New insight into silica deposition in horsetail (Equisetum arvense).
New insight into silica deposition in horsetail (Equisetum arvense).
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DOI：
10.1186/1471-2229-11-112
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发表时间：
2011-07-29
影响因子：
5.3
通讯作者：
Exley C
中科院分区：
文献类型：
--
作者：
Law C;Exley C
马尾草（Equisetum sp）是已知的生物硅化剂，尽管这些植物中二氧化硅沉积的机制仍然很大程度上未知。从水培生长的马尾和从野外收集的马尾组织提取物中提取，在微波炉中酸消化，并使用荧光显微镜、PDMPO和荧光显微镜观察它们的二氧化硅“骨架”。从根茎到茎、叶和孢子的所有植物区域都有二氧化硅沉积。在不同的分化阶段，细胞壁、细胞板、胞间连丝、保护细胞和气孔等许多结构都发生硅化。马尾中二氧化硅沉积的所有主要位置都模拟了已知发现半纤维素、胼胝质的位置和结构，这些偶然观察到的二氧化硅和胼胝质的巧合提出了胼胝质可能是马尾中二氧化硅沉积的模板的可能性。在没有硅酸的情况下，水培马尾的结果是正常健康的植物，经过酸消化，在其组织中没有任何二氧化硅沉积。为了验证胼胝质可能是模板的假设，将市售的胼胝质与不饱和和饱和硅酸溶液混合，并通过荧光法和荧光显微镜证明了二氧化硅的形成。由胼胝质引发二氧化硅形成是第一个例子，其中任何生物分子已被证明可以诱导，而不是催化，在硅酸的不饱和溶液中形成二氧化硅。这一新发现使我们推测胼胝质及其相关的生化机制可能是我们对生物硅化的理解中缺失的一环。
The horsetails (Equisetum sp) are known biosilicifiers though the mechanism underlying silica deposition in these plants remains largely unknown. Tissue extracts from horsetails grown hydroponically and also collected from the wild were acid-digested in a microwave oven and their silica 'skeletons' visualised using the fluor, PDMPO, and fluorescence microscopy. Silica deposits were observed in all plant regions from the rhizome through to the stem, leaf and spores. Numerous structures were silicified including cell walls, cell plates, plasmodesmata, and guard cells and stomata at varying stages of differentiation. All of the major sites of silica deposition in horsetail mimicked sites and structures where the hemicellulose, callose is known to be found and these serendipitous observations of the coincidence of silica and callose raised the possibility that callose might be templating silica deposition in horsetail. Hydroponic culture of horsetail in the absence of silicic acid resulted in normal healthy plants which, following acid digestion, showed no deposition of silica anywhere in their tissues. To test the hypothesis that callose might be templating silica deposition in horsetail commercially available callose was mixed with undersaturated and saturated solutions of silicic acid and the formation of silica was demonstrated by fluorimetry and fluorescence microscopy. The initiation of silica formation by callose is the first example whereby any biomolecule has been shown to induce, as compared to catalyse, the formation of silica in an undersaturated solution of silicic acid. This novel discovery allowed us to speculate that callose and its associated biochemical machinery could be a missing link in our understanding of biosilicification.
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DOI：
10.1073/pnas.0606330103
发表时间：
2006-11-14
影响因子：
11.1
作者：
Fauteux, Francois;Chain, Florian;Belanger, Richard R.
通讯作者：
Belanger, Richard R.
影响因子：
4.2
作者：
Apostolakos, P.;Livanos, P.;Galatis, B.
通讯作者：
Galatis, B.
影响因子：
4.2
作者：
Currie, Heather A.;Perry, Carole C.
通讯作者：
Perry, Carole C.
影响因子：
9.4
作者：
Apostolakos, P.;Livanos, P.;Galatis, B.
通讯作者：
Galatis, B.
影响因子：
5.3
作者：
Nishikawa S;Zinkl GM;Swanson RJ;Maruyama D;Preuss D
通讯作者：
Preuss D