Regulation and Functional Analysis of ZmDREB2A in Response to Drought and High Temperature Stress from Zea mays L.

Abstract

We cloned a DREB2 homolog from maize, named ZmDREB2A, whose transcripts were accumulated by cold, dehydration, salt and high temperature stresses. Additionally, alternative splicing of ZmDREB2A was observed and quantitative real-time PCR revealed that the functional splicing form of ZmDREB2A transcript was more significantly accumulated under stress conditions. An enhanced drought stress tolerance was observed in 35S:ZmDREB2A and rd29A:ZmDREB2A plants. Twenty-two-thousand oligo microarray analyses of the 35S:ZmDREB2A plants revealed that in addition to genes encoding LEA proteins, some heat shock inducible genes were upregulated by ZmDREB2A. As expected, we found that the 35S:ZmDREB2A plants showed an improved thermotolerance compared with wild-type plants. In conclusion, ZmDREB2A plays an important role not only in water deficit response, but also involved in high temperature response in plant.