Sassa H, Hirano H
Kihara Institute for Biological Research, Yokohama City University, Japan.
Planta. 1998 Aug;205(4):514-21. doi: 10.1007/s004250050350.
The stylar proteins of Japanese pear (Pyrus serotina Rehd.) were analyzed by two-dimensional gel electrophoresis, and a 32-kDa protein with an isoelectric point of 4.8 was found to be a major component in the style. The 32-kDa protein was a soluble glycoprotein which reacted with concanavalin A. The 32-kDa protein specifically accumulated in the style in a developmentally regulated manner, but was not detected in the other floral organs and leaves. An oligonucleotide representing the N-terminal amino acid sequence of the 32-kDa protein was used to amplify a cDNA fragment by polymerase chain reaction (PCR). The generated PCR product was used to screen a style cDNA library. The selected cDNA clone encoded 244 amino acid residues containing the N-terminal sequence of the 32-kDa protein. The N-terminus of the protein was preceded by putative signal peptide of 22 amino acid residues. The 32-kDa protein showed significant homology with the thaumatin/PR5-like proteins, and was named PsTL1 (Pyrus serotina thaumatin-like protein 1). The possible biological role of PsTL1 in the styles is discussed.
通过二维凝胶电泳分析了日本梨（Pyrus serotina Rehd.）花柱蛋白，发现一种等电点为4.8的32 kDa蛋白是花柱中的主要成分。该32 kDa蛋白是一种可与伴刀豆球蛋白A反应的可溶性糖蛋白。32 kDa蛋白以发育调控的方式特异性地在花柱中积累，但在其他花器官和叶片中未检测到。用代表32 kDa蛋白N端氨基酸序列的寡核苷酸通过聚合酶链反应（PCR）扩增cDNA片段。产生的PCR产物用于筛选花柱cDNA文库。所选的cDNA克隆编码244个氨基酸残基，包含32 kDa蛋白的N端序列。该蛋白的N端之前有一个22个氨基酸残基的推定信号肽。32 kDa蛋白与类甜蛋白/PR5样蛋白具有显著同源性，被命名为PsTL1（Pyrus serotina类甜蛋白1）。讨论了PsTL1在花柱中的可能生物学作用。
