Link B M, Cosgrove D J
Department of Biology, 208 Mueller Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Plant Physiol. 1998 Nov;118(3):907-16. doi: 10.1104/pp.118.3.907.
The possibility that Bright Yellow 2 (BY2) tobacco (Nicotiana tabacum L.) suspension-cultured cells possess an expansin-mediated acid-growth mechanism was examined by multiple approaches. BY2 cells grew three times faster upon treatment with fusicoccin, which induces an acidification of the cell wall. Exogenous expansins likewise stimulated BY2 cell growth 3-fold. Protein extracted from BY2 cell walls possessed the expansin-like ability to induce extension of isolated walls. In western-blot analysis of BY2 wall protein, one band of 29 kD was recognized by anti-expansin antibody. Six different classes of alpha-expansin mRNA were identified in a BY2 cDNA library. Northern-blot analysis indicated moderate to low abundance of multiple alpha-expansin mRNAs in BY2 cells. From these results we conclude that BY2 suspension-cultured cells have the necessary components for expansin-mediated cell wall enlargement.
通过多种方法研究了亮黄2（BY2）烟草（Nicotiana tabacum L.）悬浮培养细胞具有扩展素介导的酸生长机制的可能性。用诱导细胞壁酸化的藤霉素处理后，BY2细胞生长速度加快了两倍。外源扩展素同样能使BY2细胞生长加快3倍。从BY2细胞壁提取的蛋白质具有诱导离体细胞壁伸展的类扩展素能力。在对BY2细胞壁蛋白的蛋白质印迹分析中，抗扩展素抗体识别出一条29 kD的条带。在BY2 cDNA文库中鉴定出六种不同类型的α-扩展素mRNA。Northern印迹分析表明，BY2细胞中多种α-扩展素mRNA的丰度中等至较低。从这些结果我们得出结论，BY2悬浮培养细胞具有扩展素介导的细胞壁扩大所需的成分。
