Overexpression of Antarctic CBF genes increased the stress tolerance in rice plants

Abstract

C-repeat/dehydration-responsive element binding factors (CBF/DREBs) are a family of transcription factors that play a key role in regulating freezing tolerance, binding to the DRE/CRT cis-acting elelment commonly present in stress responsive genes in plant species. As a step towards understanding the stress response of antarctic vascular plants, we have researched CBF genes in Deschampsia antarctica, the only natural grass species colonized in the Maritime Antarctic, isolated CBF orthologs and developed the stress tolerant transgenic crop by overexpression of Deschampsia CBF genes (DaCBFs) in rice. For example, Transgenic over-expression of DaCBF7 in rice (pUBI::CBF7) resulted in a dramatic increase in tolerance to low-temperature stress, while the response high salinity or dehydration was not changed, suggesting that DaCBF7 gene is specifically related to cold tolerance response. To describe the cold-tolerance phenotype of the transgenic rice, we compared the transcriptome response between wild type rice and transgenic rices and identified a set of genes regulated by overexpression of DaCBFs in response to cold stress.