| Summary: | 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 <i>DREB</i> gene, <i>ZmDREB2.9</i>, in the <i>Zea mays</i> cv. B73 genome and compared its expression profile with those of the known A2-type maize genes <i>ZmDREB2.1–2.8</i>. <i>ZmDREB2.9</i> was mapped to chromosome 8, contained 18 predicted hormone- and stress-responsive <i>cis</i>-elements in the promoter, and had two splice isoforms: short <i>ZmDREB2.9-S</i> preferentially expressed in the leaves, embryos, and endosperm and long <i>ZmDREB2.9-L</i> expressed mostly in the male flowers, stamens, and ovaries. Phylogenetically, ZmDREB2.9 was closer to <i>A. thaliana</i> DREB2A than the other ZmDREB2 factors. <i>ZmDREB2.9-S</i>, <i>ZmDREB2.2</i>, and <i>ZmDREB2.1/2A</i> were upregulated in response to cold, drought, and abscisic acid and may play redundant roles in maize stress resistance. <i>ZmDREB2.3</i>, <i>ZmDREB2.4</i>, and <i>ZmDREB2.6</i> were not expressed in seedlings and could be pseudogenes. <i>ZmDREB2.7</i> and <i>ZmDREB2.8</i> showed similar transcript accumulation in response to cold and abscisic acid and could be functionally redundant. Our results provide new data on <i>Z. mays</i> DREB2 factors, which can be used for further functional studies as well as in breeding programs to improve maize stress tolerance.
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