loading page

Divalent nutrient cations: friend and foe during zinc stress in rice
  • +3
  • Boon Huat Cheah,
  • Yu-Ling Chen,
  • Jing-Chi Lo,
  • I-Chien Tang,
  • Kuo-Chen Yeh,
  • YA-FEN LIN
Boon Huat Cheah
National Taiwan University
Author Profile
Yu-Ling Chen
National Taiwan University
Author Profile
Jing-Chi Lo
Academia Sinica
Author Profile
I-Chien Tang
Academia Sinica
Author Profile
Kuo-Chen Yeh
Academia Sinica
Author Profile
YA-FEN LIN
National Taiwan University
Author Profile

Abstract

Zn deficiency is the most common micronutrient deficit in rice but also a widespread industrial pollutant. It is unclear how rice responds to Zn depletion or excess, and which signaling molecules link the affected physiological processes. We therefore compared the physiological, transcriptomic and biochemical properties of rice plants subjected to Zn starvation or excess at early and later treatment stages. Both forms of Zn stress inhibited root and shoot growth. Several divalent cations (Fe, Cu, Ca, Mn and Mg) accumulated in Zn-depleted shoots, possibly due to the increased synthesis and activity of promiscuous Zn transporters and chelators. Gene Ontology enrichment analysis of 970 differentially expressed genes revealed overrepresentation of ion and oligopeptide transport, antioxidative defense and secondary metabolism. The expression of genes encoding Fe/Ca-binding peroxidases was activated after 3 days of Zn starvation, boosting the activity of ascorbate peroxidase and thus scavenging H2O2 more effectively to prevent leaf chlorosis. Conversely, excess Zn triggered the expression of genes encoding Mg-binding proteins (OsCPS2/4 and OsKSL4/7) required for antimicrobial diterpenoid biosynthesis. We demonstrated the key components of crosstalk between Zn and other divalent cations under Zn stress conditions, leading to the regulation of gene expression and corresponding biochemical and physiological processes.

Peer review status:UNDER REVIEW

12 Jul 2020Submitted to Plant, Cell & Environment
14 Jul 2020Assigned to Editor
14 Jul 2020Submission Checks Completed
30 Jul 2020Reviewer(s) Assigned
09 Sep 2020Review(s) Completed, Editorial Evaluation Pending