AXY3 encodes a α-xylosidase that impacts the structure and accessibility of the hemicellulose xyloglucan in Arabidopsis plant cell walls.
AXY3 encodes a α-xylosidase that impacts the structure and accessibility of the hemicellulose xyloglucan in Arabidopsis plant cell walls.
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DOI：
10.1007/s00425-010-1330-7
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发表时间：
2011-04
期刊：
影响因子：
4.3
通讯作者：
Pauly M
中科院分区：
文献类型：
--
作者：
Günl M;Pauly M
木葡聚糖是双子叶植物如拟南芥细胞壁中最丰富的半纤维素。它是植物细胞承重结构的一部分，其新陈代谢被认为在细胞伸长中发挥着重要作用。然而，木葡聚糖在植物中执行此功能和其他功能的分子机制尚不清楚。我们利用木葡聚糖寡糖质量分析对化学诱变的拟南芥幼苗进行了正向遗传筛选，以鉴定具有改变的木葡聚糖结构的突变体，称为axy突变体。已鉴定的突变体之一 axy3.1 含有具有较高比例非岩藻糖基化木葡聚糖亚基的木葡聚糖。绘图显示，axy3.1 在 XYLOSIDASE1 (XYL1) 中包含一个点突变，该突变已知编码质外体糖苷水解酶，在非还原端从木葡聚糖寡糖中释放木糖基残基。这些数据支持以下假设：AXY3/XYL1 是质外体木葡聚糖降解机制的重要组成部分，并且由于各种 axy3 等位基因缺乏功能，不仅导致木葡聚糖结构改变，而且导致木葡聚糖与其他壁成分的关联不太紧密。然而，植物可以相对较好地应对过量的木葡聚糖，因为突变体不表现出任何可见的生长或形态表型，除了较短的长角果和降低的适应性之外。总而言之，这些结果表明植物质外体水解酶对壁聚合物结构和功能的影响比之前想象的更大。本文的在线版本 (doi:10.1007/s00425-010-1330-7) 包含补充材料，可供授权用户使用。
Xyloglucan is the most abundant hemicellulose in the walls of dicots such as Arabidopsis. It is part of the load-bearing structure of a plant cell and its metabolism is thought to play a major role in cell elongation. However, the molecular mechanism by which xyloglucan carries out this and other functions in planta is not well understood. We performed a forward genetic screen utilizing xyloglucan oligosaccharide mass profiling on chemically mutagenized Arabidopsis seedlings to identify mutants with altered xyloglucan structures termed axy-mutants. One of the identified mutants, axy3.1, contains xyloglucan with a higher proportion of non-fucosylated xyloglucan subunits. Mapping revealed that axy3.1 contains a point mutation in XYLOSIDASE1 (XYL1) known to encode for an apoplastic glycoside hydrolase releasing xylosyl residues from xyloglucan oligosaccharides at the non-reducing end. The data support the hypothesis that AXY3/XYL1 is an essential component of the apoplastic xyloglucan degradation machinery and as a result of the lack of function in the various axy3-alleles leads not only to an altered xyloglucan structure but also a xyloglucan that is less tightly associated with other wall components. However, the plant can cope with the excess xyloglucan relatively well as the mutant does not display any visible growth or morphological phenotypes with the notable exception of shorter siliques and reduced fitness. Taken together, these results demonstrate that plant apoplastic hydrolases have a larger impact on wall polymer structure and function than previously thought. The online version of this article (doi:10.1007/s00425-010-1330-7) contains supplementary material, which is available to authorized users.
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DOI：
10.1073/pnas.94.5.2085
发表时间：
1997-03-04
影响因子：
11.1
作者：
Bonin, CP;Potter, I;Reiter, WD
通讯作者：
Reiter, WD
影响因子：
4.3
作者：
Louvet, Romain;Cavel, Emilie;Pelloux, Jerome
通讯作者：
Pelloux, Jerome
影响因子：
7.4
作者：
Monroe, JD;Gough, CM;Wright, PW
通讯作者：
Wright, PW
果皮同质分离剂掩盖了植物细胞壁中丰富的木葡聚糖表位。
影响因子：
5.3
作者：
Marcus SE;Verhertbruggen Y;Hervé C;Ordaz-Ortiz JJ;Farkas V;Pedersen HL;Willats WG;Knox JP
通讯作者：
Knox JP
影响因子：
6.4
作者：
MURASHIGE, T;SKOOG, F
通讯作者：
SKOOG, F