A galactose-rich, cell-wall glycoprotein from styles of Nicotiana alata.
A galactose-rich, cell-wall glycoprotein from styles of Nicotiana alata.
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一种来自翼形烟草的富含半乳糖的细胞壁糖蛋白。
DOI：
10.1046/j.1365-313x.1996.09010071.x
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
A. Bacic
中科院分区：
文献类型：
--
作者：
J. Sommer;A. Clarke;A. Bacic
从烟草（Nicotiana阿拉塔）花柱中分离到一种富含半乳糖的花柱碱性糖蛋白（GaRSGP），该糖蛋白由花柱特异性cDNA（NaPRP 4）编码。糖蛋白与传输道中的细胞壁相关，由约25%（w/w）蛋白质和75%（w/w）碳水化合物组成。纯化的糖蛋白在SDS-PAGE上显示为45-120 kDa之间的涂片;去糖基化的蛋白骨架具有约30 kDa的表观分子量。该糖蛋白富含赖氨酸、脯氨酸和羟脯氨酸等氨基酸以及半乳糖和阿拉伯糖等单糖。它是仅有的几个脯氨酸/羟脯氨酸丰富的糖蛋白（P/HRGPs），其特征在于作为cDNA克隆和蛋白质之一。聚糖通过O-和N-糖苷键连接到蛋白质骨架上，其中大部分碳水化合物是O-连接的，并且由主要终止于半乳糖残基的短的高度支化的链组成。在GaRSGP和另一种花柱特异性糖蛋白上发现了碳水化合物表位，但在来自其他组织的糖蛋白上没有发现。这一发现为花柱特异性碳水化合物表位的存在提供了进一步的证据，该表位可能在花柱功能中发挥作用。
A basic, galactose-rich style glycoprotein (GaRSGP) encoded by a previously characterized style-specific cDNA (NaPRP4) has been isolated from the styles of Nicotiana alata and structurally characterized. The glycoprotein is associated with cell walls in the transmitting tract and is composed of approximately 25% (w/w) protein and 75% (w/w) carbohydrate. The purified glycoprotein appears as a smear of between 45-120 kDa on SDS-PAGE; the deglycosylated protein backbone has an apparent molecular weight of approximately 30 kDa. The glycoprotein is rich in the amino acids lysine, proline, and hydroxyproline and in the monosaccharides galactose and arabinose. It is one of only a few proline/hydroxyproline-rich glycoproteins (P/HRGPs) to be characterized both as a cDNA-clone and protein. Glycans are attached to the protein backbone through both O- and N-glycosidic linkages with the majority of the carbohydrate being O-linked and consisting of short, highly branched chains terminating primarily in galactose residues. A carbohydrate epitope(s) is found on both GaRSGP and another style-specific glycoprotein but not on glycoproteins from other tissues. This finding provides further evidence for the existence of a style-specific carbohydrate epitope(s) which may play a role in style function.