JXB Advance Access originally published online on December 9, 2005
Journal of Experimental Botany 2006 57(1):201-212; doi:10.1093/jxb/erj026
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RESEARCH PAPER |
Role of abscisic acid (ABA) and Arabidopsis thaliana ABA-insensitive loci in low water potential-induced ABA and proline accumulation

Department of Botany and Plant Sciences and Center for Plant Cell Biology, University of California, Riverside, CA 92521, USA
* To whom correspondence should be addressed. E-mail: paul.verslues{at}ucr.edu
The mechanisms by which plants respond to reduced water availability (low water potential) include both ABA-dependent and ABA-independent processes. Pro accumulation and osmotic adjustment are two important traits for which the mechanisms of regulation by low water potential, and the involvement of ABA, is not well understood. The ABA-deficient mutant, aba2-1, was used to investigate the regulatory role of ABA in low water potential-induced Pro accumulation and osmotic adjustment in seedlings of Arabidopsis thaliana. Low water potential-induced Pro accumulation required wild-type levels of ABA, as well as a change in ABA sensitivity or ABA-independent events. Osmotic adjustment, in contrast, occurred independently of ABA accumulation in aba2-1. Quantification of low water potential-induced ABA and Pro accumulation in five ABA-insensitive mutants, abi1-1, abi2-1, abi3, abi4, and abi5, revealed that abi4 had increased Pro accumulation at low water potential, but a reduced response to exogenous ABA. Both of these responses were modified by sucrose treatment, indicating that ABI4 has a role in connecting ABA and sugar in regulating Pro accumulation. Of the other abi mutants, only abi1 had reduced Pro accumulation in response to low water potential and ABA application. It was also observed that abi1-1 and abi2-1 had increased ABA accumulation. The involvement of these loci in feedback regulation of ABA accumulation may occur through an effect on ABA catabolism or conjugation. These data provide new information on the function of ABA in seedlings exposed to low water potential and define new roles for three of the well-studied abi loci.
Key words: ABA (abscisic acid), ABA sensitivity, abi mutants, abiotic stress, Arabidopsis thaliana, low water potential, osmotic adjustment, proline
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
A. Ben Hassine, M. E. Ghanem, S. Bouzid, and S. Lutts Abscisic acid has contrasting effects on salt excretion and polyamine concentrations of an inland and a coastal population of the Mediterranean xero-halophyte species Atriplex halimus Ann. Bot., October 1, 2009; 104(5): 925 - 936. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Pitzschke and H. Hirt Disentangling the Complexity of Mitogen-Activated Protein Kinases and Reactive Oxygen Species Signaling Plant Physiology, February 1, 2009; 149(2): 606 - 615. [Full Text] [PDF] |
||||
![]() |
C. Vasquez-Robinet, S. P. Mane, A. V. Ulanov, J. I. Watkinson, V. K. Stromberg, D. De Koeyer, R. Schafleitner, D. B. Willmot, M. Bonierbale, H. J. Bohnert, et al. Physiological and molecular adaptations to drought in Andean potato genotypes J. Exp. Bot., May 1, 2008; 59(8): 2109 - 2123. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Efetova, J. Zeier, M. Riederer, C.-W. Lee, N. Stingl, M. Mueller, W. Hartung, R. Hedrich, and R. Deeken A Central Role of Abscisic Acid in Drought Stress Protection of Agrobacterium-Induced Tumors on Arabidopsis Plant Physiology, November 1, 2007; 145(3): 853 - 862. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Kariola, G. Brader, E. Helenius, J. Li, P. Heino, and E. T. Palva EARLY RESPONSIVE TO DEHYDRATION 15, a Negative Regulator of Abscisic Acid Responses in Arabidopsis Plant Physiology, December 1, 2006; 142(4): 1559 - 1573. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Rosado, A. L. Schapire, R. A. Bressan, A. L. Harfouche, P. M. Hasegawa, V. Valpuesta, and M. A. Botella The Arabidopsis Tetratricopeptide Repeat-Containing Protein TTL1 Is Required for Osmotic Stress Responses and Abscisic Acid Sensitivity Plant Physiology, November 1, 2006; 142(3): 1113 - 1126. [Abstract] [Full Text] [PDF] |
||||


