GsTIFY10, a novel positive regulator of plant tolerance
to bicarbonate stress and a repressor of jasmonate signaling
Dan Zhu
•
Xi Bai
•
Chao Chen
•
Qin Chen
•
Hua Cai
•
Yong Li
•
Wei Ji
•
Hong Zhai
•
Dekang Lv
•
Xiao Luo
•
Yanming Zhu
Received: 12 May 2011 / Accepted: 13 July 2011 / Published online: 31 July 2011
Ó Springer Science+Business Media B.V. 2011
Abstract Recent discoveries show that TIFY family
genes are plant-specific genes involved in the response to
several abiotic stresses, also acting as key regulators of
jasmonate signaling in Arabidopsis thaliana. However,
there is limited information about this gene family in wild
soybean, nor is its role in plant bicarbonate stress adapta-
tion completely understood. Here, we isolated and char-
acterized a novel TIFY family gene, GsTIFY10, from
Glycine soja. GsTIFY10 could be induced by bicarbonate,
salinity stress and the phytohormone JA, both in the leaves
and roots of wild soybean. Over-expression of GsTIFY10 in
Arabidopsis resulted in enhanced plant tolerance to bicar-
bonate stress during seed germination, early seedling and
adult seedling developmental stages, and the expression
levels of some bicarbonate stress response and stress-
inducible marker genes were significantly higher in the
GsTIFY10 overexpression lines than in wild-type plants. It
was also found that GsTIFY10 could repress JA signal
transduction. The roots of plants overexpressing GsTIFY10
grew longer than wild-type in the presence of MeJA, and
some JA response and JA biosynthesis marker genes were
suppressed in the GsTIFY10 overexpression lines. Subcel-
lular localization studies using a GFP fusion protein
showed that GsTIFY10 is localized to the nucleus. These
results suggest that the newly isolated wild soybean
GsTIFY10 is a positive regulator of plant bicarbonate stress
tolerance and is also a repressor of jasmonate signaling,
from hormone perception to transcriptional activity.
Keywords Bicarbonate stress tolerance Á GsTIFY10 Á
Jasmonate signaling Á Repressor Á Glycine soja
Introduction
Bicarbonate stress, including Na
?
, high pH, CO
3
2-
and
HCO
3
-
, elicits adverse effects on the growth and produc-
tivity of crops. Bicarbonate supplied as NaHCO
3
, can
inhibit new root and shoot growth due to the excessive
accumulation of organic acids such as malate, succinate
and citrate (Yang et al. 1994a, b). Plants have developed
various biochemical and physiological mechanisms to
endure and adapt to bicarbonate stress. According to the
classic biochemical pH–stat regulation hypothesis, HCO
3
-
,
as a substrate, can activate phosphoenolpyruvate carbox-
ylase (PEPCase) with optimal activity under alkaline
conditions. As a result, the production of malic acid is
triggered, and considerable alkalization of cytosol is pre-
vented. When the cytoplasm is acidified by excessive malic
acid, PEPCase activity is suppressed while NADP-depen-
dent malic enzyme (NADP-ME) is activated, with its
optimal activity under more acidic conditions, followed by
increasing decarboxylation of malic acid and the prevent-
ing cytoplasm aciditication (Davies 1986; Sakano 1998;
Gout et al. 1992).
Plants also evolved complex systems of signal percep-
tion and transduction in order to respond to adverse envi-
ronmental changes (Casal 2002). Jasmonate, a small plant
signaling molecule, is well known as an important effector
in plant responses to environmental stresses (Devoto and
D. Zhu Á X. Bai Á C. Chen Á H. Cai Á Y. Li Á W. Ji Á H. Zhai Á
D. Lv Á X. Luo Á Y. Zhu (&)
Plant Bioengineering Laboratory, Northeast Agricultural
University, Harbin 150030, China
e-mail: ymzhu@neau.edu.cn
Q. Chen
Lethbridge Research Centre, Agriculture and Agri-Food Canada,
5403-1 Ave, South P.O. Box 3000, Lethbridge, AB T1J 4B1,
Canada
123
Plant Mol Biol (2011) 77:285–297
DOI 10.1007/s11103-011-9810-0