Cloning Of AtDOF1 Gene In Arabidopsis And Its Functional Validation In Transgenic Maize

Maize is China’s first major grain crops and needs more nitrogen.However, the utilization of nitrogen fertilizer is low, which results in the nutritional deficiencies of nitrogen in maize growth periods. Therefore, the cultivation of maize varieties with efficient utilization of nitrogen is becoming a hotspot of wide attention. DOF transcription factor is a plant specific transcription factor. Studies have shown that many DOF transcription factors can regulate the activity of key enzymes in the process of carbon and nitrogen metabolism to increase the nitrogen absorption of plants and improve plant agronomic traits.To explore the physiological and biochemical function of AtDOF1 gene in maize, the experiments that the pCAM3300-ubi-AtDOF1 plant expression vector was constructed, and the the plant expression vector was transformed to embryos by Agrobacterium transformation method that can obtain the transgenic maize plants; Through analyzing the expression of the downstream regulation gene,the enzyme activity,the nitrogen stress experiment in greenhouse that measure the chlorophyll content of plants and the changes of the specific growth rate, as well as the field indicators that includ the chlorophyll content and the total nitrogen content to explore the biological function of the gene.The results show that: the expression of AtDOF1 gene may activate two genes those are the key enzyme phosphoenolpyruvate(PEPC) and pyruvate kinase(PK) of carbon and nitrogen metabolism in maize, and make the two enzymes’ activity increase, thus the AtDOF1 can contribut to the carbon and nitrogen metabolism of maize; Through the nitrogen stress experiments in greenhouse, the results show that the gene under normal nitrogen treatment in maize may have a higher content of chlorophyll and the specific growth rate, suggesting that the gene could play the function that can promote the nitrogen absorption at normal nitrogen treatment; The results in the field show that the chlorophyll content and the total nitrogen content are increased in the transgenic plants under different nitrogen treatment; Based on the above results, in this study the function of At DOF1 genes is preliminarily analysed, for further resolve mechanism and regulatory pathways of DOF transcription factor provides some theoretical basises.