Two cotton fiber-associated glycosyltransferases, GhGT43A1 and GhGT43C1, function in hemicellulose glucuronoxylan biosynthesis during plant development
Two cotton fiber-associated glycosyltransferases, GhGT43A1 and GhGT43C1, function in hemicellulose glucuronoxylan biosynthesis during plant development
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两种棉纤维相关糖基转移酶 GhGT43A1 和 GhGT43C1 在植物发育过程中的半纤维素葡糖醛酸木聚糖生物合成中发挥作用
DOI：
10.1111/ppl.12190
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发表时间：
2014-10-01
影响因子：
6.4
通讯作者：
Xu, Wenliang
中科院分区：
文献类型：
--
作者：
Li, Long;Huang, Junfeng;Xu, Wenliang
木聚糖是双子叶植物次生细胞壁的主要半纤维素成分。棉纤维细胞壁组成在整个发育过程中动态变化。在棉纤维发育过程中，半纤维素多糖的含量和分子大小都发生了显著变化。然而，没有一个编码负责合成木聚糖的糖基转移酶（GT）的基因在棉纤维中被分离和鉴定。在这项研究中，我们应用生物信息学的方法，并确定了两个推定的转基因棉花，命名为GhGT43A1和GhGT43C1，属于CAZy GT43家族，并密切相关的拟南芥IRX9和IRX14，分别。GhGT43 A1在花后15天和20天的棉纤维中高度优先表达，而GhGT43 C1在大多数器官中普遍表达，尤其是在花后15天的棉纤维和下胚轴中表达最高。互补序列分析表明GhG43A1和GhGT 43C1分别与拟南芥IRX9和IRX14同源。此外，我们表明，在拟南芥中过表达GhGT43A1或GhGT43C1的结果增加木聚糖含量。我们还表明，GhGT43A1或GhGT43C1的过表达导致更多的纤维素沉积。这些发现表明GhGT 43 A1和GhGT 43 C1可能参与纤维发育过程中木聚糖的合成。
Xylan is the major hemicellulosic constituent in dicot secondary cell walls. Cell wall composition of cotton fiber changes dynamically throughout development. Not only the amounts but also the molecular sizes of the hemicellulosic polysaccharides show substantial changes during cotton fiber development. However, none of the genes encoding glycosyltransferases (GTs) responsible for synthesizing xylan have been isolated and characterized in cotton fiber. In this study, we applied a bioinformatics approach and identified two putative GTs from cotton, designated GhGT43A1 and GhGT43C1, which belong to the CAZy GT43 family and are closely related to ArabidopsisIRX9 and IRX14, respectively. We show that GhGT43A1 is highly and preferentially expressed in 15 and 20days post-anthesis (dpa) cotton fiber, whereas GhGT43C1 is ubiquitously expressed in most organs, with especially high expression in 15 dpa fiber and hypocotyl. Complementation analysis demonstrates that GhG43A1 and GhGT43C1 are orthologs of ArabidopsisIRX9 and IRX14, respectively. Furthermore, we show that overexpression of GhGT43A1 or GhGT43C1 in Arabidopsis results in increased xylan content. We also show that overexpression of GhGT43A1 or GhGT43C1 leads to more cellulose deposition. These findings suggest that GhGT43A1 and GhGT43C1 likely participate in xylan synthesis during fiber development.