Improving plant drought, salt, and freezing tolerance by gene transfer of a single stress-inducible transcription factor

Mie Kasuga¹, Qiang Liu^1,2, Setsuko Miura¹, Kazuko Yamaguchi-Shinozaki¹ & Kazuo Shinozaki³

Abstract

Plant productivity is greatly affected by environmental stresses such as drought, salt loading, and freezing. We reported previously that a cis -acting promoter element, the dehydration response element (DRE), plays an important role in regulating gene expression in response to these stresses. The transcription factor DREB1A specifically interacts with the DRE and induces expression of stress tolerance genes. We show here that overexpression of the cDNA encoding DREB1A in transgenic plants activated the expression of many of these stress tolerance genes under normal growing conditions and resulted in improved tolerance to drought, salt loading, and freezing. However, use of the strong constitutive 35S cauliflower mosaic virus (CaMV) promoter to drive expression of DREB1A also resulted in severe growth retardation under normal growing conditions. In contrast, expression of DREB1Afrom the stress inducible rd29A promoter gave rise to minimal effects on plant growth while providing an even greater tolerance to stress conditions than did expression of the gene from the CaMV promoter.

drought tolerancefreezing tolerancetransgenic plantsmultigene expressionstress-inducible promotertopof page

1. Biological Resources Division, Japan International Research Center for Agricultural Sciences (JIRCAS), Ministry of Agriculture, Forestry and Fisheries, 2-1 Ohwashi, Tsukuba, Ibaraki 305-8686, Japan.
2. Present address: Department of Biological Sciences and Biotechnology, Tsinghua University, Tsinghua Yuan, Haidian, Beijing 100084, China.
3. Laboratory of Plant Molecular Biology, Tsukuba Life Science Center, The Institute of Physical and Chemical Research (RIKEN), 3-1-1 Koyadai, Tsukuba, Ibaraki 305-0074 , Japan.

Correspondence to: Kazuko Yamaguchi-Shinozaki¹ e-mail: [e-mail]