Integrating physiological and transcriptome analyses clarified the molecular regulation mechanism of PyWRKY48 in poplar under cadmium stress

Xiaolu Wu; Lulu Chen; Xinyi Lin; Xiaoxi Chen; Chengyu Han; Feifei Tian; Xueqin Wan; Qinglin Liu; Fang He; Lianghua Chen; Yu Zhong; Hanbo Yang; Fan Zhang

doi:10.1016/j.ijbiomac.2023.124072

Integrating physiological and transcriptome analyses clarified the molecular regulation mechanism of PyWRKY48 in poplar under cadmium stress

Int J Biol Macromol. 2023 May 31:238:124072. doi: 10.1016/j.ijbiomac.2023.124072. Epub 2023 Mar 17.

Authors

Xiaolu Wu¹, Lulu Chen¹, Xinyi Lin¹, Xiaoxi Chen¹, Chengyu Han¹, Feifei Tian¹, Xueqin Wan², Qinglin Liu¹, Fang He², Lianghua Chen², Yu Zhong², Hanbo Yang², Fan Zhang³

Affiliations

¹ College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
² College of Forestry, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
³ College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China. Electronic address: 13305@sicau.edu.cn.

PMID: 36934813
DOI: 10.1016/j.ijbiomac.2023.124072

Abstract

WRKY transcription factors (TFs) play an important role in regulating plant growth and responses to environmental stress. However, the molecular mechanism of WRKY to cadmium (Cd) stress is unclear, which prevents phytoremediation of Cd-contaminated soil from widely application. To determine the underlying mechanism, PyWRKY48-overexpressing poplars were obtained (OE-32 and OE-67) to study the Cd tolerance and accumulation in poplars. Results showed that the Cd content in the aboveground part of the two transgenic poplar lines were 1.57 and 1.99 times higher than that of wild type (WT), and lateral roots, GSH, PCs content and GST activity increased significantly. RNA-seq. data about transgenic and WT poplars revealed that 2074 differentially expressed genes (DEGs) in roots, 4325 in leaves, and 499 in both tissues. And these DEGs were mainly concentrated in ABC transport protein (PaABC), heavy-metal binding protein (PaHIPP), and transportation and loading of xylem (PaNPF, PaBSP) proteins, and they enhanced Cd accumulation. Meanwhile, PyWRKY48 increased the Cd tolerance of transgenic poplars by up-regulating the expression of PaGRP, PaPER and PaPHOS, which encode cell wall proteins, antioxidant enzyme, and heavy metal-associated proteins, respectively. In addition, overexpression PyWRKY48 promoted poplar growth by increasing the chlorophyll and carotenoid content. ENVIRONMENTAL IMPLICATION: This study generated PyWRKY48-overexpressing poplars and functionally verified them in Cd-contaminated soil, to analyze the effects of the gene on poplar growth, Cd tolerance and Cd accumulation. RNA seq. data revealed that several genes are involved in Cd exposure. This may provide a strong molecular basis and new ideas for improving the phytoremediation efficiency of Cd-contaminated soils. Importantly, the transgenic poplars grew better and accumulated more Cd than the wild-type. Therefore, PyWRKY48-overexpressing poplars could be considered useful for mitigating environmental pollution.

Keywords: Cadmium; Poplar; PyWRKY48.

MeSH terms

Antioxidants / pharmacology
Biodegradation, Environmental
Cadmium / metabolism
Gene Expression Profiling
Metals, Heavy* / metabolism
Plant Roots
Populus* / metabolism
Soil / chemistry
Soil Pollutants* / metabolism
Stress, Physiological / genetics

Substances

Cadmium
Metals, Heavy
Antioxidants
Soil
Soil Pollutants