Figure 8.

Proposed mechanisms of overexpression of TaCOMT to enhance drought tolerance and participate in GA and IAA Pathway in Arabidopsis. Under drought condition, the expression of TaCOMT increased melatonin synthesis in plants. The increasing of melatonin content leads to the decrease of IAA level and the changing of transcription of drought-related genes, and, then, enhancing drought tolerance in plants. The increasing of melatonin content can also improve the drought tolerance of plants. Under normal conditions, overexpression of TaCOMT increased the content of melatonin in plants. High levels of melatonin promoted early flowering and involved in the GA pathway.