Sievers A, Buchen B, Hodick D
Botanisches Institut, Universitat Bonn, Germany.
Trends Plant Sci. 1996 Aug;1(8):273-9. doi: 10.1016/1360-1385(96)10028-5.
In addition to the statocytes of roots and shoots, a number of tip-growing cells also sense gravity, which influences the cells' growth and development. Since these tip-growing cells are highly suitable for observations in vivo, the movement and sedimentation of their statoliths can be studied in detail. Experimental manipulation by centrifugation, drug application, optical tweezers or microgravity can be monitored by light microscopy. The statoliths are localized in distinct cytoplasmic areas by interactions with actin filaments or microtubules, and their sedimentation seems to be narrowly confined. Since gravisensing and the graviresponse take place within the same cell, the gravitropic signal transduction chain is not complicated by signal transmission between sensing and responding cells. Studies on tip-growing cells have now enabled the formulation of models explaining positive and negative gravitropism.
除了根和茎的平衡细胞外，许多顶端生长的细胞也能感知重力，这会影响细胞的生长和发育。由于这些顶端生长的细胞非常适合进行体内观察，因此可以详细研究其平衡石的运动和沉降。通过离心、药物处理、光镊或微重力进行的实验操作可以通过光学显微镜进行监测。平衡石通过与肌动蛋白丝或微管的相互作用定位于不同的细胞质区域，并且它们的沉降似乎受到严格限制。由于重力感知和重力响应发生在同一个细胞内，重力信号转导链不会因传感细胞和响应细胞之间的信号传递而变得复杂。目前，对顶端生长细胞的研究已经能够建立解释正向和负向重力性的模型。
