Functions of dopamine in plants: a review

Abstract

Dopamine (3-hydroxytyramine or 3,4-dihydroxyphenethylamine) has many functions in animals, but also shows several other functions in plants. Since the discovery of dopamine in plants in 1968, many studies have provided insight into physiological and biochemical functions, and stress responses of this molecule. In this review, we describe the biosynthesis of dopamine, as well as its role in plant growth and development. In addition, endogenous or exogenously applied dopamine improved the tolerance against several abiotic stresses, such as drought, salt, and nutrient stress. There are also several studies that dopamine contributes to the plant immune response against plant disease. Dopamine affects the expression of many abiotic stresses related genes, which highlights its role as a multi-regulatory molecule and can coordinate many aspects of plant development. Our review emphasized the effects of dopamine against environmental stresses along with future research directions, which will help improve the yield of eco-friendly crops and ensure food security.

Keywords: 3,4- dihydroxy phenethylamine; abiotic stress; biosynthetic pathway; biotic stress; plant.

Figure 1.

(a) Structures of dopamine and (b) evolution of the number of articles related with dopamine in plants from 2000 to 2020 (Jan to Sep)

Figure 2.

Dopamine biosynthetic pathways in plants

Figure 3.

Schematic of dopamine’s positive effects on physiological processes. Abiotic and biotic stressors provoke an increase into endogenous dopamine level through the upregulation of dopamine biosynthetic genes (panel A). Stressors act as negative effectors in many physiological processes such as carbon and nitrogen metabolism, photosynthesis, and hormone levels (panel B). Endogenous dopamine can regulate the expression of many genes and regulatory factors, which can reduce the negative effects of biotic/abiotic stressors on physiological processes (panels C)