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 should be addressed to Kazuko Yamaguchi-Shinozaki kazukoys@jircas.affrc.go.jpdrought tolerancefreezing tolerancetransgenic plantsmultigene expressionstress-inducible promoter
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 DREB1A from
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.
