Department of Biological Sciences, Stanford University, Stanford, California 94305.
Plant Physiol. 1974 Oct;54(4):499-502. doi: 10.1104/pp.54.4.499.
Auxin promotes the liberation of a xlyoglucan polymer from the cell walls of elongating pea (Pisum sativum) stem segments. The released polymer can be isolated from the polysaccharide fraction of the water-soluble portion of tissue homogenates, thus providing as assay for this kind of metabolism. Promotion of xyloglucan metabolism by auxin begins within 15 minutes of hormone presentation. The effect increases with auxin concentration in a manner similar to the hormone effect on elongation. However, the xyloglucan effect of auxin occurs perfectly normally when elongation is completely blocked by mannitol. Metabolic inhibitors and Ca(2+), on the other hand, inhibit auxin promotion of elongation and of xyloglucan metabolism in parallel. The results suggest that the changes in xyloglucan reflect the means by which auxin modifies the cell wall to cause elongation.
生长素促进豌豆（Pisum sativum）茎段伸长区细胞壁中木葡聚糖聚合物的释放。释放的聚合物可从组织匀浆水溶性部分的多糖组分中分离出来，因此可作为这种代谢的一种测定方法。生长素促进木葡聚糖代谢的作用在激素处理 15 分钟内开始。该作用随生长素浓度的增加而增加，与激素对伸长的作用方式相似。然而，当甘露醇完全阻断伸长时，生长素对木葡聚糖的作用仍然正常。另一方面，代谢抑制剂和 Ca(2+) 则平行地抑制生长素对伸长和木葡聚糖代谢的促进作用。结果表明，木葡聚糖的变化反映了生长素改变细胞壁以引起伸长的方式。
