Division of Biological and Medical Research, Argonne National Laboratory, Argonne, Illinois 60439.
Plant Physiol. 1974 Mar;53(3):398-401. doi: 10.1104/pp.53.3.398.
Gravity compensation by the horizontal clinostat increases the diameter of amyloplast starch grains of oat (Avena sativa cv. Victory) coleoptile parenchyma cells, as compared to vertically rotated and stationary controls. In dark-grown coleoptile tip parenchyma cells, measured starch grain sizes exhibit a wide distribution of diameters, from approximately 1.5 to approximately 8.0 mum, but fall into three prominent diameter classes. The compensated tissues from both the tip and the subapical region have more starch grains in the larger, and fewer in the smaller size classes, compared to controls. The total number of starch grains per cell, the total plastid number per cell, and cell volume are unaffected by gravity compensation. Amyloplasts with large starch grains are denser, as well as larger in diameter, than those with smaller starch grains. The amyloplast is considered as a geosensor with an active metabolic role in the geotropic transduction mechanism.
与垂直旋转和静置对照相比，水平回旋器的重力补偿增加了燕麦（Avena sativa cv. Victory）胚芽鞘薄壁细胞的淀粉体淀粉粒的直径。在黑暗生长的胚芽鞘顶端薄壁细胞中，测量的淀粉粒大小表现出直径的广泛分布，从大约 1.5 到大约 8.0 微米，但分为三个明显的直径类群。与对照相比，来自顶端和亚顶端区域的补偿组织中较大的淀粉粒数量较多，较小的淀粉粒数量较少。每个细胞的淀粉粒总数、每个细胞的质体总数和细胞体积不受重力补偿的影响。具有大淀粉粒的淀粉体比具有小淀粉粒的淀粉体密度更大，直径也更大。淀粉体被认为是地球传感器，在向地性转导机制中具有活跃的代谢作用。
