Plant fertility is dramatically affected by spikes in temperature, directly resulting in yield reduction and economic loss. Understanding the molecular mechanisms that underpin plant fertility under environmental constraints is critical to safeguarding food production.
In the paper, 'A transposon surveillance mechanism that safeguards plant male fertility during stress', published in the journal Nature Plants, led by researchers from the School of Life Sciences at the University of Warwick have studied the molecular mechanisms that maize plants utilise to safeguard fertility under high temperatures, and identified two Argonaute-like (AGO) proteins that protect the male sex cells.
Male fertility
By subjecting maize plants with non-functional AGO proteins to different growth conditions, researchers discovered that a 5?C increase in ambient temperature dramatically decreased male fertility.
Using a multidisciplinary approach, the team found that higher temperatures activated small pieces of ribonucleic acid (or small RNAs) in wild-type plants, which bind to these AGO proteins to control the activity of stress-activated jumping genes -- pieces of DNA that can copy themselves into different parts of the genome. Therefore, these AGO proteins control the activity of jumping-genes, thereby protect plant fertility.
Surveillance mechanisms
Professor Jose Gutierrez-Marcos, from the School of Life Sciences at the University of Warwick explains: "We have essentially found that when plants are stressed by high temperatures they activate an RNA-guided surveillance mechanism in the form of small RNAs and Argonaute proteins, in reproductive cells which are critical to sustain male fertility and ultimately plant survival. "Understanding the molecular mechanism implicated in safeguarding plant fertility is critical to safeguard future crop production under unpredictable and stressful climatic conditions."
Dr Charo del Genio, from the School of Computing, Electronics and Mathematics at Coventry University adds: "Modelling the structure of the Argonaute proteins and simulating them at the level of the single atoms revealed how they change their electric charge when subject to thermal stress, initiating the process that brings the jumping genes back under control."
Read the complete article at www.sciencedaily.com.
Yang-Seok Lee, Robert Maple, Julius Dürr, Alexander Dawson, Saleh Tamim, Charo del Genio, Ranjith Papareddy, Anding Luo, Jonathan C. Lamb, Stefano Amantia, Anne W. Sylvester, James A. Birchler, Blake C. Meyers, Michael D. Nodine, Jacques Rouster, Jose Gutierrez-Marcos. A transposon surveillance mechanism that safeguards plant male fertility during stress. Nature Plants, 2021; 7 (1): 34 DOI: 10.1038/s41477-020-00818-5