Department of Soil and Crop Sciences, Texas A & M University, College Station, Texas 77843.
Plant Physiol. 1987 Sep;85(1):261-7. doi: 10.1104/pp.85.1.261.
We investigated the proteins extractable from cell walls of stem tissues when plants were subjected to low water potentials (low psi(w)). Dark-grown soybean seedlings (Glycine max [L.] Merr.) showed decreased stem growth when the roots were exposed to vermiculite having low water content (psi(w) = -3 bar). After a time, growth resumed but at a reduced rate relative to the controls. The extractable protein increased in the cell walls as psi(w) decreased, especially a 28-kilodalton protein in the young tissue. In contrast, a 70 kilodalton protein, mainly extractable from mature cell walls, appeared to decrease slightly at low psi(w). No hydroxyproline was present in either protein, which shows that neither protein is related to extensin. The level of the 28 kilodalton protein increased in the cell wall of the dividing region soon after the initial growth inhibition, and it appeared in the elongating tissue at about the time growth resumed. The correlation between growth and these protein changes suggests that the two events could be related.
当植物处于低水势（低 psi(w)）时，我们研究了细胞壁中可提取的蛋白质。黑暗中生长的大豆幼苗（Glycine max [L.] Merr.）在根系暴露于含水量低的蛭石（psi(w)=-3 巴）时，茎的生长会减少。一段时间后，生长会恢复，但相对于对照物，生长速度会降低。随着 psi(w)的降低，细胞壁中可提取的蛋白质增加，尤其是在年轻组织中 28 千道尔顿的蛋白质。相比之下，主要从成熟细胞壁中提取的 70 千道尔顿蛋白质在低 psi(w)下似乎略有减少。两种蛋白质都没有羟脯氨酸，这表明它们都与伸展蛋白无关。28 千道尔顿蛋白质的水平在初始生长抑制后不久在分裂区的细胞壁中增加，并在生长恢复时出现在伸长组织中。生长和这些蛋白质变化之间的相关性表明，这两个事件可能有关。
