Dataset Information

Characterization of Glutamate-Mediated Hormonal Regulatory Pathway of the Drought Responses in Relation to Proline Metabolism in Brassica napus L.

ABSTRACT: Proline metabolism influences the metabolic and/or signaling pathway in regulating plant stress responses. This study aimed to characterize the physiological significance of glutamate (Glu)-mediated proline metabolism in the drought stress responses, focusing on the hormonal regulatory pathway. The responses of cytosolic Ca²⁺ signaling, proline metabolism, and redox components to the exogenous application of Glu in well-watered or drought-stressed plants were interpreted in relation to endogenous hormone status and their signaling genes. Drought-enhanced level of abscisic acid (ABA) was concomitant with the accumulation of ROS and proline, as well as loss of reducing potential, which was assessed by measuring NAD(P)H/NAD(P)⁺ and GSH/GSSG ratios. Glu application to drought-stressed plants increased both salicylic acid (SA) and cytosolic Ca²⁺ levels, with the highest expression of calcium-dependent protein kinase (CPK5) and salicylic acid synthesis-related ICS1. The SA-enhanced CPK5 expression was closely associated with further enhancement of proline synthesis-related genes (P5CS1, P5CS2, and P5CR) expression and a reset of reducing potential with enhanced expression of redox regulating genes (TRXh5 and GRXC9) in a SA-mediated NPR1- and/or PR1-dependent manner. These results clearly indicate that Glu-activated interplay between SA- and CPK5-signaling as well as Glu-enhanced proline synthesis are crucial in the amelioration of drought stress in Brassica napus.

SUBMITTER: La VH

PROVIDER: S-EPMC7237994 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Characterization of Glutamate-Mediated Hormonal Regulatory Pathway of the Drought Responses in Relation to Proline Metabolism in <i>Brassica napus</i> L.

La Van Hien VH Lee Bok-Rye BR Islam Md Tabibul MT Mamun Md Al MA Park Sang-Hyun SH Bae Dong-Won DW Kim Tae-Hwan TH

Plants (Basel, Switzerland) 20200416 4

Proline metabolism influences the metabolic and/or signaling pathway in regulating plant stress responses. This study aimed to characterize the physiological significance of glutamate (Glu)-mediated proline metabolism in the drought stress responses, focusing on the hormonal regulatory pathway. The responses of cytosolic Ca<sup>2+</sup> signaling, proline metabolism, and redox components to the exogenous application of Glu in well-watered or drought-stressed plants were interpreted in relation t ...[more]

PMID: 32316109

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Dataset Information

Characterization of Glutamate-Mediated Hormonal Regulatory Pathway of the Drought Responses in Relation to Proline Metabolism in Brassica napus L.

Publications

Characterization of Glutamate-Mediated Hormonal Regulatory Pathway of the Drought Responses in Relation to Proline Metabolism in <i>Brassica napus</i> L.

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