摘要
The beneficial role of melatonin (MT) as a potent broad-spectrum antioxidant and hormone-like regulator in plant protection against adverse environmental conditions is indisputable. However, the molecular networks underlying its unique scavenging capabilities are still far from understood. Herein, we show the ability of MT to maintain physiological functions under high light stress (HL) is mediated by photoreceptors. Melatonin treatment (50 μM) of the photoreceptor mutants phyA/B and cry1/2 augmented the deleterious effects of excess light (600 μmol m−2 s−1, 24 h), as evidenced by increased TBARs levels and electrolyte leakage, as well as decreased photosynthetic efficiency, in contrast to their parental form, Landsberg erecta, in which these parameters were significantly improved. The reduced stress resistance of the mutants was also confirmed by analysis of the transcript accumulation of ROS markers and enzymatic scavengers. Moreover, the increase in melatonin content in the mutants exposed to HL + MT contributed to increased ROS accumulation; therefore, the deleterious effect of MT could not be explained by an imbalance in ROS production below the cytostatic level. We hypothesize that the light-sensitive phenotypes of photoreceptor mutants under MT treatment may be due to the misregulation of stress-related genes that are targets for melatonin action.
摘要译文
褪黑激素（MT）作为有效的抗氧化剂和激素样调节剂在植物保护抗体环境条件中的有益作用是无可争议的。但是，其独特的清除功能的分子网络远未被理解。在本文中，我们显示了MT在高光应力（HL）下保持生理功能的能力是由感光体介导的。光感受器突变体Phya/b和Cry1/2的褪黑激素处理（50μM）增强了过度光的有害影响（600μmolM -2 s -1，24 h），与TBARS水平和电解质泄漏的提高相比，相比之下，相比之下，与他们的光合效率相比，较低的是，这些效率是由TBARS水平和电解质渗漏所提高，相比之下。通过分析ROS标记物和酶脱腔剂的转录本积累，也证实了突变体的应激耐药性降低。此外，暴露于HL + MT的突变体中褪黑激素含量的增加导致ROS积累增加。因此，MT的有害作用无法通过低于细胞抑制水平的ROS产生的不平衡来解释。我们假设在MT处理下，光感受器突变体的光敏感表型可能是由于压力相关的基因的不正调，这是褪黑激活的靶标。
Ivan Bychkov [1];Anastasia Doroshenko [2];Natalia Kudryakova (https://orcid.org/0000-0002-3979-1554) [3];Victor Kusnetsov (https://orcid.org/0000-0003-4979-6137) [4];. Photoreceptors Are Involved in Antioxidant Effects of Melatonin Under High Light in Arabidopsis[J]. Antioxidants, 2025,14(4): 458