PlantView Supports Wheat Drought Tolerance Research: TaERF87 and TaAKS1 synergistically regulate TaP5CS1/TaP5CR1-mediated proline biosynthesis to enhance drought tolerance in wheat

New progress has been made in elucidating the molecular mechanism of wheat drought tolerance.

Academician Zhensheng Kang and Professor Hude Mao’s research team from Northwest A&F University have made new advances in understanding the molecular regulation mechanisms underlying drought resistance in wheat. Their findings were published in “New Phytologists” (IF = 10.323, Q1 journal).

This study reveals a TaABF2–TaERF87/TaAKS1–TaP5CS1/TaP5CR1 regulatory module that enhances wheat drought tolerance by synergistically promoting proline biosynthesis and maintaining cellular osmotic balance, providing important candidate genes and theoretical foundations for drought-resistant wheat breeding.

Wheat is one of the world’s most important staple crops and is widely cultivated in arid and semi-arid regions. However, frequent drought events caused by global climate change pose severe threats to wheat yield and global food security. Under drought stress, plants accumulate osmoprotective substances such as proline to maintain cellular osmotic balance and reduce damage. Proline biosynthesis is mainly catalyzed by the enzymes P5CS and P5CR, but the transcriptional regulatory mechanisms and upstream regulators controlling this process remain largely unclear. Transcription factors play essential roles in plant drought responses. Among them, the ERF and bHLH families are important regulatory factors, and several members have been shown to participate in drought tolerance regulation. However, the functions and regulatory networks of many ERF and bHLH transcription factors in wheat remain largely unexplored, highlighting the need to identify drought-resistance-related candidate genes and further understand wheat drought adaptation mechanisms.

In this study, RNA-seq combined with weighted gene co-expression network analysis (WGCNA) identified the ERF family transcription factor TaERF87 as a central hub gene in the wheat drought response network. Functional analyses demonstrated that overexpression of TaERF87 significantly enhanced drought tolerance in wheat, whereas silencing TaERF87 reduced drought resistance. Mechanistically, TaERF87 directly binds to the GCC-box elements in the promoters of proline biosynthesis genes TaP5CS1 and TaP5CR1, activating their expression and promoting proline accumulation. Further investigations revealed that TaERF87 physically interacts with the bHLH transcription factor TaAKS1, and the two proteins synergistically enhance the transcriptional activation of TaP5CS1 and TaP5CR1. Overexpression of TaAKS1 also improves wheat drought tolerance by promoting proline biosynthesis. In addition, both TaERF87 and TaAKS1 are target genes of the ABA-responsive factor TaABF2. TaABF2 binds to the ABRE elements in their promoters and activates their expression. Collectively, this study uncovers the molecular mechanism by which the TaABF2–TaERF87/TaAKS1–TaP5CS1/TaP5CR1 regulatory module enhances wheat drought tolerance through coordinated regulation of proline biosynthesis and cellular osmotic homeostasis, providing valuable genetic resources and theoretical support for the development of drought-resistant wheat varieties.

Experiments using Plantview

The PlantView plant in vivo imaging system from Guangzhou Biolight was employed in this study for LCI-based imaging analysis, enabling the visualization and investigation of the interaction between TaERF87 and TaAKS1 proteins.

DOI: org/10.1111/nph.18549