α粒子注入对拟南芥胚根生长及向重力性的影响

Root gravitropism change induced by 241Am α-particle irradiation on Arabidopsis embryos

本研究用分子探针、外源过氧化氢、活性氧猝灭剂和测量根长等实验方法,研究了α粒子注入拟南芥胚引起拟南芥根弯曲的原因。研究表明,在0-100Gy辐照范围内,α粒子注入拟南芥胚引起的根弯曲与剂量呈正相关(r=0.98),1Gy、10Gy、100Gy处理的拟南芥幼苗根的弯曲度分别为13.3°、28.7°、69.1°,非照射对照为12.5°。当剂量为100Gy时,根呈"S"形弯曲,根的向重力性降低,根生长受到抑制。活性氧在根部的产生率检测表明,100Gyα粒子处理的根尖较对照有较亮的活性氧显色。适当浓度的活性氧猝灭剂处理,可以使α粒子注入引起的根长及向重力性得以恢复,且外源过氧化氢能够诱导拟南芥根弯曲加重。该研究显示,α粒子注入拟南芥胚引起的根长及向重力性变化是活性氧介导的。

To study root curve induced by 241Am α-particle irradiation on Arabidopsis embryos, molecular probe assay, outside-H2O2 assay, ROS-extinguisher assay and root measurement assay are adopted. The study shows that root curve angles induced by 241Am α-particle irradiation on Arabidopsis embryos have a positive relation （r=-0.98） with irradiated doses within 100Gy. Root curve angle of 1Gy, 10Gy, 100Gy, and control is 13.3°, 28.7°, 69.1°, 12.5° respectively. Root of 100Gy treatment shows an ＂S＂ type curve while root growth is restrainded. Pseudo-color images of CM-H2DCFDA, which represents quantity of ROS in root tip, shows brighter in 100Gy irradiated group than that in the non-irradiated group. Root length and root gravitropism recover occurs when suitable concentration of scavenger of ROS is used. And root curvation has been observed while asymmetric replacement of H2O2 used. The study indicated that α-particle-induced the change of root growth and root gravitropism might be due to ROS.