Expression Analysis Of Transcription Factors Families Under Drought Stress In Maize

Drought is the major limiting factor of maize production, and the molecular mechanism of maize drought stress gene response is one of the core theories of maize molecular breeding. Through plant transcription factors binding to cis-elements in the promoter regions to inhibit or activate the transcription, they respond to a series of environmental stress factors such as drought, salt stress, low temperature, hormone. Responses of maize transcription factors to drought stress are poorly understand. In this research the expression characteristics of maize transcription factors are analyzed based on bio informatics methods and transcriptome-based high-throughput data, to provide a theoretical basis and genetic materials for maize drought breeding.The materials are H-21and Ye478which have different sensitivities to drought stress. To obtain their digital gene expression profiles, total RNA was sequenced that extracted from the whole plants which encountered proper drought stress at the seedling stage. Based on the digital gene expression profiles and the maize transcription factor database in ProFITS site, statistical analysis of genes with significant expression in transcription factors family indicate that:the numbers of transcription factor genes with significantly up-regulated expression in H-21and Ye478are166and315, respectively, and they have40in common; the numbers with significantly down-regulated expression are166and315, respectively, and26in common. Based on digital gene expression profiles of these transcription factors, metabolic regulation network involved them was analyzed via gene ontology analysis tools, which showed that these genes have roles in various biological pathways such as nitrogen metabolism, macromolecule metabolism, RNA metabolism, signal conduction, organelle synthesis and abiotic stresses.To detect the tissue expression specificity characteristics of some members in ARF, AP2-EREBP and SBP family, H-21, Ye478and their hybrid Fl were used as the material, and real-time PCR was performed. The research showed that:under moderate drought stress, ARF, the ERF and SBP genes were up-regulated expressed in leaves, and mainly down-regulated expressed in roots; under severe drought stress, the ARF, the ERF and SBP genes were down-regulated expressed in roots, and up-regulated expressed in the leaves of H-21, down-regulated expressed in the leaves of Ye478and Fl. From the tests, we noted that ARF3and ARF5have the dose effect, and some members of the NAC family involved in the negative regulation of metabolic pathways of the cell wall.