ABA has been widely acknowledged to regulate ethylene biosynthesis and signaling during fruit ripening, but the molecular mechanism underlying the interaction between these two hormones are largely unexplored. In the present study, exogenous ABA treatment obviously promoted fruit ripening as well as ethylene emission, whereas NDGA (Nordihydroguaiaretic acid, an inhibitor of ABA biosynthesis) ap...

The plant hormones abscisic acid (ABA), jasmonic acid (JA), and ethylene are involved in diverse plant processes, including the regulation of gene expression during adaptive responses to abiotic and biotic stresses. Previously, ABA has been implicated in enhancing disease susceptibility in various plant species, but currently very little is known about the molecular mechanisms underlying this p...

The plant hormone abscisic acid (ABA) mediates seed dormancy, controls seedling development and triggers tolerance to abiotic stresses, including drought. Core ABA signaling components consist of a recently identified group of ABA receptor proteins of the PYRABACTIN RESISTANCE (PYR)/REGULATORY COMPONENT OF ABA RECEPTOR (RCAR) family that act as negative regulators of members of the PROTEIN PHOS...

Using a newly developed abscisic acid (ABA)-affinity chromatography technique, we showed that the magnesium-chelatase H subunit ABAR/CHLH (for putative abscisic acid receptor/chelatase H subunit) specifically binds ABA through the C-terminal half but not the N-terminal half. A set of potential agonists/antagonists to ABA, including 2-trans,4-trans-ABA, gibberellin, cytokinin-like regulator 6-be...

Ethylene and abscisic acid (ABA) act synergistically or antagonistically to regulate plant growth and development. ABA is derived from the carotenoid biosynthesis pathway. Here, we analyzed the interplay among ethylene, carotenoid biogenesis, and ABA in rice (Oryza sativa) using the rice ethylene response mutant mhz5, which displays a reduced ethylene response in roots but an enhanced ethylene ...

The production of reactive oxygen species (ROS) is one of the first defense reactions induced in Arabidopsis in response to infection by the pectinolytic enterobacterium Dickeya dadantii. Previous results also suggest that abscisic acid (ABA) favors D. dadantii multiplication and spread into its hosts. Here, we confirm this hypothesis using ABA-deficient and ABA-overproducer Arabidopsis plants....

The oxidative cleavage of cis-epoxycarotenoids catalyzed by 9-cis-epoxycarotenoid dioxygenase (NCED) is considered to be the rate-limiting step in abscisic acid (ABA) biosynthesis. Here we demonstrate that the expression of AhNCED1 gene in peanut plants is significantly up-regulated by dehydration and high salinity. The AhNCED1 transcript and endogenous ABA both accumulate predominantly in leav...

H(2)O(2) is known as a signal molecule in plant cells, but its role in the regulation of aqbscisic acid (ABA) and gibberellic acid (GA) metabolism and hormonal balance is not yet clear. In this study it was found that H(2)O(2) affected the regulation of ABA catabolism and GA biosynthesis during seed imbibition and thus exerted control over seed dormancy and germination. As seen by quantitative ...

When mature green harvested Shamouti oranges (Citrus sinensis L. Osbeck) were exposed to 35 mul/liter of ethylene, a 3-fold increase in free abscisic acid (ABA) of the flavedo could be detected after 12 hours and a 10-fold increase after 24 hours, while chlorophyll destruction did not exceed 20%. The increase in free ABA continued up to 24 hours and leveled off. Bound ABA accumulated strongly a...

Glucose modulates plant metabolism, growth, and development. In Arabidopsis (Arabidopsis thaliana), Hexokinase1 (HXK1) is a glucose sensor that may trigger abscisic acid (ABA) synthesis and sensitivity to mediate glucose-induced inhibition of seedling development. Here, we show that the intensity of short-term responses to glucose can vary with ABA activity. We report that the transient (2 h/4 ...