RT Journal Article
SR Electronic
T1 Drought Induction of Arabidopsis 9-cis-Epoxycarotenoid Dioxygenase Occurs in Vascular Parenchyma Cells
JF Plant Physiology
JO Plant Physiol.
FD American Society of Plant Biologists
SP 1984
OP 1993
DO 10.1104/pp.108.116632
VO 147
IS 4
A1 Endo, Akira
A1 Sawada, Yoshiaki
A1 Takahashi, Hirokazu
A1 Okamoto, Masanori
A1 Ikegami, Keiichi
A1 Koiwai, Hanae
A1 Seo, Mitsunori
A1 Toyomasu, Tomonobu
A1 Mitsuhashi, Wataru
A1 Shinozaki, Kazuo
A1 Nakazono, Mikio
A1 Kamiya, Yuji
A1 Koshiba, Tomokazu
A1 Nambara, Eiji
YR 2008
UL http://www.plantphysiol.org/content/147/4/1984.abstract
AB The regulation of abscisic acid (ABA) biosynthesis is essential for plant responses to drought stress. In this study, we examined the tissue-specific localization of ABA biosynthetic enzymes in turgid and dehydrated Arabidopsis (Arabidopsis thaliana) plants using specific antibodies against 9-cis-epoxycarotenoid dioxygenase 3 (AtNCED3), AtABA2, and Arabidopsis aldehyde oxidase 3 (AAO3). Immunohistochemical analysis revealed that in turgid plants, AtABA2 and AAO3 proteins were localized in vascular parenchyma cells most abundantly at the boundary between xylem and phloem bundles, but the AtNCED3 protein was undetectable in these tissues. In water-stressed plants, AtNCED3 was detected exclusively in the vascular parenchyma cells together with AtABA2 and AAO3. In situ hybridization using the antisense probe for AtNCED3 showed that the drought-induced expression of AtNCED3 was also restricted to the vascular tissues. Expression analysis of laser-microdissected cells revealed that, among nine drought-inducible genes examined, the early induction of most genes was spatially restricted to vascular cells at 1 h and then some spread to mesophyll cells at 3 h. The spatial constraint of AtNCED3 expression in vascular tissues provides a novel insight into plant systemic response to drought stresses.