Characterization of the primary cell walls of seedlings of Brachypodium distachyon - A potential model plant for temperate grasses
Characterization of the primary cell walls of seedlings of Brachypodium distachyon - A potential model plant for temperate grasses
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DOI：
10.1016/j.phytochem.2009.09.019
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发表时间：
2010-01-01
期刊：
影响因子：
3.8
通讯作者：
Harholt, Jesper
中科院分区：
文献类型：
--
作者：
Christensen, Ulla;Alonso-Simon, Ana;Harholt, Jesper
短尾草（Brachypodium distachyon），也被称为紫假雀科（purple false brome），其基因组在2008年被完全测序，主要是为了响应对温带禾草模式植物的需求。对三种小麦（Triticum aestivum）幼苗的初代细胞壁进行了比较研究。这三个物种的细胞壁的特点是半纤维素的相对水平和发育变化相似。（1,3;1,4）- β - d -葡聚糖的出现与涉及细胞伸长的生长阶段相关。参与(1,3;1,4)- β - d -葡聚糖合成的基因（纤维素合成酶样F家族（CSLF）、CSLH和一个假定的合成酶基因CSLJ）的表达谱未显示出与(1,3;1,4)- β - d -葡聚糖丰度相对应的转录调控。CSLF6转录本在所有三种禾本科植物中都具有相似的高表达，并且比其他任何转录本都要丰富得多。CSLH转录物在双歧杆菌中相对丰富，而在其他物种中几乎检测不到。在三种禾本科植物的幼苗生长过程中，阿拉伯木聚糖的沉积量稳步增加，但在细胞成熟过程中，阿拉伯木聚糖的取代量减少，交联量增加。此外，与其他两种禾草相比，双歧草中的阿拉伯木聚糖具有较低的阿拉伯糖取代程度，较高的二聚体形式的阿魏酸百分比和较大的酯连接对香豆酸比例。2009爱思唯尔有限公司版权所有。
The genome of Brachypodium distachyon, also known as purple false brome, was fully sequenced in 2008 largely in response to the demand for a model plant for temperate grasses. A comparative study of the primary cell walls of seedlings of B. distachyon, Hordeum vulgare and Triticum aestivum was carried out. The cell walls of the three species were characterized by similar relative levels of, and developmental changes in, hemicelluloses. The occurrence of (1,3;1,4)-beta-D-glucans was correlated with phases of growth involving cell elongation. Expression profiling of the genes involved in (1,3;1,4)-beta-D-glucan synthesis (cellulose synthase-like F family (CSLF), CSLH and a putative synthase gene CSLJ) did not show a transcriptional regulation that corresponded to the abundance of (1,3;1,4)-beta-D-glucans. CSLF6 transcripts were similarly highly expressed in all three grasses, and were much more abundant than any of the other transcripts. The CSLH transcript was relatively abundant in B. distachyon but almost undetectable in the other species. The deposition of arabinoxylans increased steadily during seedling growth in all three grasses, but they became less substituted and more cross-linked into the wall matrix during cell maturation. Moreover, arabinoxylans in B. distachyon differed from the two other grasses in having a lower degree of arabinose substitution, a higher percentage of ferulic acid in form of dimers and a larger proportion of ester-linked p-coumaric acid. (C) 2009 Elsevier Ltd. All rights reserved.