Identification of microRNA-target interactions for antioxidant defense response under drought stress by high-throughput sequencing in Zanthoxylum bungeanum Maxim

Abstract

12When the plant is in an unfavorable environment such as drought or high temperature, it will 13 accumulate a large amount of active oxygen, which will seriously affect the normal growth and 14 development of the plant. The antioxidant system can remove the reactive oxygen species 15 produced under drought conditions and so mitigate oxidative damage. We examined the trends of 16 antioxidant enzymes, miRNAs and their target genes in Zanthoxylum bungeanum under drought 17 stress. According to the changes of antioxidant enzymes, miRNAs and their target genes 18 expression patterns of Zanthoxylum bungeanum under drought stress, an interaction model was 19 constructed to provide a reference for further understanding of plant antioxidant mechanism. The 20 results indicate that under drought stress, POD, CAT, APX, proline, MDA and related genes all 21show positive responses to drought, while SOD and its genes showed a negative response. It is 22 23 play a major role, and SOD plays a supporting role. In addition, the expression levels of miRANs 24 and their target genes were basically negatively correlated, indicating that miRNAs are involved 25 in the regulation of the antioxidant system of Zanthoxylum bungeanum. 26 Keywords：antioxidant system; Zanthoxylum bungeanum Maxim.; reactive oxygen species; 27 drought stress；miRNA-Target gene 28 29 42 Drought stress can cause a series of physiological and molecular reactions in plants, which 43 seriously affect normal growth. Thus, drought can cause imbalances in cellular reactive oxygen 44 3 species (ROS), it can also upset cell membrane lipid peroxidation and it can damage cell and 45 organelle membranes. Excessive ROS have toxic effects on plants. Irrigated agriculture is not yet 46 general, so drought remains one of the most important unfavorable factors affecting both the 47