Researchers Uncover Acetylation-mediated Regulatory Mechanisms of Desiccation Tolerance in Desert Moss

A study led by Prof. ZHANG Daoyuan from the Xinjiang Institute of Ecology and Geography (XIEG) of the Chinese Academy of Sciences has uncovered the acetylation-mediated regulatory mechanisms underlying the desiccation tolerance of Syntrichia caninervis, a model moss for desiccation tolerance research. The study was published in Plant Physiology on March 16.

The researchers employed high-throughput acetylomics, a technique that maps chemical modifications on proteins, to profile the lysine acetylome of Syntrichia caninervis during dehydration-rehydration cycles. As a result, they identified 11,474 acetylation sites across 4,171 proteins—the largest dataset in plants ever reported to date.

The study reveals that a process called lysine acetylation acts as a sophisticated "switch" within the plant's cells. During dehydration, this modification precisely fine-tunes metabolic pathways to bolster cellular stability and maintain a healthy internal chemical balance (redox homeostasis), essentially shielding the plant from damage.

But upon rehydration, lysine acetylation rapidly redirects its efforts. It specifically targets crucial processes like glycolysis (the breakdown of sugars for energy) and the proteasome (the cell's clean-up and repair crew) to kickstart energy production and initiate cellular repair, enabling a swift and robust recovery.

A noteworthy finding is that Syntrichia caninervis employs a unique molecular fingerprint for this acetylation process. Unlike many other plant species that rely on amino acids like histidine, tyrosine, and phenylalanine for such modifications, this moss exhibits a distinct preference for leucine.

The researchers further pinpointed a specific protein, pyruvate kinase cPK5, demonstrating that acetylation at a particular site (lysine 513) is critical for itscatalytic activity and stability. This enhancement directly contributes to the moss's ability to tolerate drying.

This study delineates the dynamic regulatory network of lysine acetylation in an extremophile plant, offering invaluable new insights into how plants adapt to severe water stress and holds significant promise for breeding crops that are more resilient to drought.

Read the full article: https://doi.org/10.1093/plphys/kiag139

Contact

LONG Huaping

Xinjiang Institute of Ecology and Geography

E-mail: longhp@ms.xjb.ac.cn

Web: http://english.egi.cas.cn