Melatonin Confers Plant Cadmium Tolerance: An Update

International Journal of Molecular Sciences

Yi Han¹  Quan Gu²  Qingqing Xiao²  Chuyan Wang²  Ziping Chen³ 

[1] National Engineering Laboratory of Crop Stress Resistence Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China;School of Biology, Food and Environment, Hefei University, Hefei 230601, China;State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China;

关键词: antioxidant defense systems;    Cd stress;    hydrogen sulfide;    melatonin;    oxidative stress;    transportation and sequestration;   

DOI  :  10.3390/ijms222111704

来源: DOAJ

【 摘 要 】

Cadmium (Cd) is one of the most injurious heavy metals, affecting plant growth and development. Melatonin (N-acetyl-5-methoxytryptamine) was discovered in plants in 1995, and it is since known to act as a multifunctional molecule to alleviate abiotic and biotic stresses, especially Cd stress. Endogenously triggered or exogenously applied melatonin re-establishes the redox homeostasis by the improvement of the antioxidant defense system. It can also affect the Cd transportation and sequestration by regulating the transcripts of genes related to the major metal transport system, as well as the increase in glutathione (GSH) and phytochelatins (PCs). Melatonin activates several downstream signals, such as nitric oxide (NO), hydrogen peroxide (H₂O₂), and salicylic acid (SA), which are required for plant Cd tolerance. Similar to the physiological functions of NO, hydrogen sulfide (H₂S) is also involved in the abiotic stress-related processes in plants. Moreover, exogenous melatonin induces H₂S generation in plants under salinity or heat stress. However, the involvement of H₂S action in melatonin-induced Cd tolerance is still largely unknown. In this review, we summarize the progresses in various physiological and molecular mechanisms regulated by melatonin in plants under Cd stress. The complex interactions between melatonin and H₂S in acquisition of Cd stress tolerance are also discussed.

【 授权许可】

Unknown