Gene in Maize ( L.): Genome-Wide Identification, Characterization, Expression, and Stress Response.

Dehydration-responsive element-binding (DREB) transcription factors of the A2 subfamily play key roles in plant stress responses. In this study, we identified and characterized a new A2-type gene, , in the cv. B73 genome and compared its expression profile with those of the known A2-type maize genes . was mapped to chromosome 8, contained 18 predicted hormone- and stress-responsive -elements in the promoter, and had two splice isoforms: short preferentially expressed in the leaves, embryos, and endosperm and long expressed mostly in the male flowers, stamens, and ovaries. Phylogenetically, ZmDREB2.9 was closer to DREB2A than the other ZmDREB2 factors. , , and were upregulated in response to cold, drought, and abscisic acid and may play redundant roles in maize stress resistance. , , and were not expressed in seedlings and could be pseudogenes. and showed similar transcript accumulation in response to cold and abscisic acid and could be functionally redundant. Our results provide new data on DREB2 factors, which can be used for further functional studies as well as in breeding programs to improve maize stress tolerance.