Institut für Genbiologische Forschung Berlin GmbH, Ihnestrasse 63, D-1000, Berlin 33.
Planta. 1989 Sep;179(2):171-80. doi: 10.1007/BF00393687.
Patatin, the most abundant protein in the storage parenchyma cells of potato (Solanum tuberosum L.) tubers, is a vacuolar glycoprotein that consists of a number of closely related polypeptides and is encoded by a large gene family. To analyse the glycosylation pattern and the nature of the glycans on a single patatin polypeptide in a heterologous tissue we introduced a single chimaeric patatin gene into tobacco (Nicotiana tabacum L.) and studied its product in leaves. Patatin isolated from the leaves of transgenic tobacco plants is glycosylated at asparagine (Asn)(60), and Asn(90), but the third glycosylation site (Asn(202)) has no glycan. The two glycans are typical small complex glycans with xylose, fucose, mannose and N-acetylglucosamine in a ratio 1:1:3:2, the same ratio as found on patatin isolated from potato tubers. Expression of patatin in tobacco leaves was accompanied by the correct processing of the signal peptide, and the proper targeting of the glyco-protein to the vacuoles of mesophyll cells.
马铃薯（Solanum tuberosum L.）块茎的贮藏组织细胞中含量最丰富的蛋白是伴刀豆球蛋白，是一种液泡糖蛋白，由许多密切相关的多肽组成，由一个大的基因家族编码。为了分析单个异源组织中伴刀豆球蛋白多肽的糖基化模式和聚糖性质，我们将单个嵌合伴刀豆球蛋白基因导入烟草（Nicotiana tabacum L.），并在叶片中研究其产物。从转基因烟草叶片中分离出的伴刀豆球蛋白在天冬酰胺（Asn）（60）和 Asn（90）处发生糖基化，但第三个糖基化位点（Asn（202））没有聚糖。这两个糖基化是典型的小复杂聚糖，木糖、岩藻糖、甘露糖和 N-乙酰葡萄糖胺的比例为 1:1:3:2，与从马铃薯块茎中分离出的伴刀豆球蛋白相同。伴刀豆球蛋白在烟草叶片中的表达伴随着信号肽的正确加工，以及糖蛋白正确靶向到质体中的液泡。
