Unraveling the role of urea hydrolysis in salt stress response during seed germination and seedling growth in Arabidopsis thaliana
- Northeast Forestry University, China
- Zhejiang A & F University, China
- University of Tokyo, Japan
Abstract
Urea is intensively utilized as a nitrogen fertilizer in agriculture, originating either from root uptake or from catabolism of arginine by arginase. Despite its extensive use, the underlying physiological mechanisms of urea, particularly its adverse effects on seed germination and seedling growth under salt stress remains unclear. In this study, we demonstrate that salt stress induces excessive hydrolysis of arginine-derived urea, leading to an increase in cytoplasmic pH within seed radical cells, which, in turn, triggers salt-induced inhibition of seed germination (SISG) and hampers seedling growth. Our findings challenge the long-held belief that ammonium accumulation and toxicity are the primary causes of SISG, offering a novel perspective on the mechanism underlying these processes. This study provides significant insights into the physiological impact of urea hydrolysis under salt stress, contributing to a better understanding of SISG.
Data availability
Figure 2 - supplement 1 - source data contain the sequences for double mutants argah1/argah2.Figure 7 - supplement 1 - source data contain the original files of the full raw unedited gels of gene expression.
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Funding
Heilongjiang Provinve Goverment Postdoctoral Science Foundation (LBH-Q18008)
- Yuanyuan Bu
Program for Changjiang Scholars and Innovative Research Team in University (IRT17R99)
- Shenkui Liu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2024, Bu et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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