|
Plant Physiol, July 2002, Vol. 129, pp. 1232-1240
Phosphite, an Analog of Phosphate, Suppresses the Coordinated
Expression of Genes under Phosphate Starvation1
Deepa K.
Varadarajan,
Athikkattuvalasu S.
Karthikeyan,
Paino Durzo
Matilda, and
Kashchandra G.
Raghothama*
Department of Horticulture and Landscape Architecture, Purdue
University, West Lafayette, Indiana 47907-1165
Phosphate (Pi) and its analog phosphite (Phi) are acquired by
plants via Pi transporters. Although the uptake and mobility of Phi and
Pi are similar, there is no evidence suggesting that plants can utilize
Phi as a sole source of phosphorus. Phi is also known to interfere with
many of the Pi starvation responses in plants and yeast
(Saccharomyces cerevisiae). In this study, effects of
Phi on plant growth and coordinated expression of genes induced by Pi
starvation were analyzed. Phi suppressed many of the Pi starvation
responses that are commonly observed in plants. Enhanced root growth
and root to shoot ratio, a hallmark of Pi stress response, was strongly
inhibited by Phi. The negative effects of Phi were not obvious in
plants supplemented with Pi. The expression of Pi starvation-induced
genes such as LePT1, LePT2,
AtPT1, and AtPT2 (high-affinity Pi
transporters); LePS2 (a novel acid phosphatase); LePS3 and TPSI1 (novel genes); and
PAP1 (purple acid phosphatase) was suppressed by Phi in
plants and cell cultures. Expression of luciferase reporter gene driven
by the Pi starvation-induced AtPT2 promoter was also
suppressed by Phi. These analyses showed that suppression of Pi
starvation-induced genes is an early response to addition of Phi. These
data also provide evidence that Phi interferes with gene expression at
the level of transcription. Synchronized suppression of multiple Pi
starvation-induced genes by Phi points to its action on the early
molecular events, probably signal transduction, in Pi starvation response.
1
This work was supported in part by the U.S.
Department of Agriculture-National Research Initiative Competitive
Grants Program (grant no. 590 1165-2614 to K.G.R.). This is
journal paper no. 16,793 of the Purdue University Agriculture Research Program.
*
Corresponding author; e-mail ragu{at}hort.purdue.edu; fax
765-494-0391.
© 2002 American Society of Plant Physiologists
This article has been cited by other articles:
|
|
|
|
 
J. P. Hammond and P. J. White
Sucrose transport in the phloem: integrating root responses to phosphorus starvation
J. Exp. Bot.,
January 1, 2008;
59(1):
93 - 109.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
B. N. Devaiah, V. K. Nagarajan, and K. G. Raghothama
Phosphate Homeostasis and Root Development in Arabidopsis Are Synchronized by the Zinc Finger Transcription Factor ZAT6
Plant Physiology,
September 1, 2007;
145(1):
147 - 159.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Yehudai-Resheff, S. L. Zimmer, Y. Komine, and D. B. Stern
Integration of Chloroplast Nucleic Acid Metabolism into the Phosphate Deprivation Response in Chlamydomonas reinhardtii
PLANT CELL,
March 1, 2007;
19(3):
1023 - 1038.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
P. Catarecha, M. D. Segura, J. M. Franco-Zorrilla, B. Garcia-Ponce, M. Lanza, R. Solano, J. Paz-Ares, and A. Leyva
A Mutant of the Arabidopsis Phosphate Transporter PHT1;1 Displays Enhanced Arsenic Accumulation
PLANT CELL,
March 1, 2007;
19(3):
1123 - 1133.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. LAMBERS, M. W. SHANE, M. D. CRAMER, S. J. PEARSE, and E. J. VENEKLAAS
Root Structure and Functioning for Efficient Acquisition of Phosphorus: Matching Morphological and Physiological Traits
Ann. Bot.,
October 1, 2006;
98(4):
693 - 713.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
K. Fujita, M. Okada, K. Lei, J. Ito, K. Ohkura, J. J. Adu-Gyamfi, and P. K. Mohapatra
Effect of P-deficiency on photoassimilate partitioning and rhythmic changes in fruit and stem diameter of tomato (Lycopersicon esculentum) during fruit growth
J. Exp. Bot.,
November 1, 2003;
54(392):
2519 - 2528.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
