Stress signaling convergence and nutrient crosstalk determine zinc-mediated amelioration against cadmium toxicity in rice

Muhammad Faheem Adil; Shafaque Sehar; Si Chen; Jonas Lwalaba Wa Lwalaba; Ghulam Jilani; Zhong-Hua Chen; Imran Haider Shamsi

doi:10.1016/j.ecoenv.2021.113128

Stress signaling convergence and nutrient crosstalk determine zinc-mediated amelioration against cadmium toxicity in rice

Ecotoxicol Environ Saf. 2022 Jan 15:230:113128. doi: 10.1016/j.ecoenv.2021.113128. Epub 2021 Dec 31.

Authors

Muhammad Faheem Adil¹, Shafaque Sehar¹, Si Chen¹, Jonas Lwalaba Wa Lwalaba¹, Ghulam Jilani², Zhong-Hua Chen³, Imran Haider Shamsi⁴

Affiliations

¹ Zhejiang Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, PR China.
² Institute of Soil Science, PMAS Arid Agriculture University, Rawalpindi 46300, Pakistan.
³ School of Science, Western Sydney University, Penrith, NSW 2751, Australia; Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia.
⁴ Zhejiang Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, PR China. Electronic address: drimran@zju.edu.cn.

PMID: 34979311
DOI: 10.1016/j.ecoenv.2021.113128

Abstract

Consumption of rice (Oryza sativa L.) is one of the major pathways for heavy metal bioaccumulation in humans over time. Understanding the molecular responses of rice to heavy metal contamination in agriculture is useful for eco-toxicological assessment of cadmium (Cd) and its interaction with zinc (Zn). In certain crops, the impacts of Cd stress or Zn nutrition on the biophysical chemistry and gene expression have been widely investigated, but their molecular interactions at transcriptomic level, particularly in rice roots, are still elusive. Here, hydroponic investigations were carried out with two rice genotypes (Yinni-801 and Heizhan-43), varying in Cd contents in plant tissues to determine their transcriptomic responses upon Cd₁₅ (15 µM) and Cd₁₅+Zn₅₀ (50 µM) treatments. High throughput RNA-sequencing analysis confirmed that 496 and 2407 DEGs were significantly affected by Cd₁₅ and Cd₁₅+Zn₅₀, respectively, among which 1016 DEGs were commonly induced in both genotypes. Multitude of DEGs fell under the category of protein kinases, such as calmodulin (CaM) and calcineurin B-like protein-interacting protein kinases (CBL), indicating a dynamic shift in hormonal signal transduction and Ca²⁺ involvement with the onset of treatments. Both genotypes expressed a mutual regulation of transcription factors (TFs) such as WRKY, MYB, NAM, AP2, bHLH and ZFP families under both treatments, whereas genes econding ABC transporters (ABCs), high affinity K⁺ transporters (HAKs) and Glutathione-S-transferases (GSTs), were highly up-regulated under Cd₁₅+Zn₅₀ in both genotypes. Zinc addition triggered more signaling cascades and detoxification related genes in regulation of immunity along with the suppression of Cd-induced DEGs and restriction of Cd uptake. Conclusively, the effective integration of breeding techniques with candidate genes identified in this study as well as economically and technologically viable methods, such as Zn nutrient management, could pave the way for selecting cultivars with promising agronomic qualities and reduced Cd for sustainable rice production.

Keywords: Cadmium toxicity; Hormonal signal transduction; Membrane transporters; Oryza sativa L.; RNA Sequencing; Zinc application.