Belyavskaya N A
Institute of Botany, Ukrainian Academy of Sciences, Kiev, USSR.
Adv Space Res. 1992;12(1):83-91. doi: 10.1016/0273-1177(92)90267-2.
The fundamental question of gravitational biology is how do plants perceive a gravity. Recent experimental results have demonstrated that Ca second-messenger system has an essential role in induction of graviresponsiveness. Our data, that stimuli of various nature cause a rise of hyaloplasm Ca level revealed by means of pyroantimonate method, as well as complete inhibition of the gravitropism in roots of pea seedlings, provide indirect but consistent evidence of this role of Ca ions. A possible explanation for these results is that they may be due to an unbalanced and undirectional influx of Ca ions in statocytes from cell walls or from intracellular Ca stores, while in the presence of the Earths 1 g vector, this process occurs directionally, along this vector. It is possible that a target for the gravity stimulus is the flux mechanism of Ca to statocytes, including participation of the phosphatidylinositol system and calmodulin. The data that have become available from space flight experiments will be reviewed and an attempt will be made to compare these results with ground-based observations.
引力生物学的基本问题是植物如何感知重力。最近的实验结果表明，钙第二信使系统在引力响应诱导中起着至关重要的作用。我们的数据显示，通过焦锑酸盐法揭示，各种性质的刺激会导致透明质Ca水平升高，以及豌豆幼苗根中向地性的完全抑制，这些数据为钙离子的这一作用提供了间接但一致的证据。对这些结果的一种可能解释是，它们可能是由于钙离子从细胞壁或细胞内钙库向平衡细胞的不平衡和无定向流入所致，而在地球1g向量存在的情况下，这一过程沿该向量定向发生。重力刺激的靶点可能是钙离子向平衡细胞的通量机制，包括磷脂酰肌醇系统和钙调蛋白的参与。将对太空飞行实验获得的数据进行综述，并尝试将这些结果与地面观测结果进行比较。
