Experts Identify Protein Network Coordinating Iron Balance Across the Entire Plant

Researchers from the Xishuangbanna Tropical Botanical Garden (XTBG) of the Chinese Academy of Sciences (CAS) have uncovered a sophisticated protein network that regulates iron balance throughout a plant's body. This discovery, published in The Plant Cell, fills a critical knowledge gap regarding how plants coordinate essential nutrient levels between their roots and shoots to maintain health.

The study identified a functional division of labor among specific proteins to manage iron homeostasis. While previous research has primarily focused on root responses, this team found that the protein BRUTUS (BTS) plays a vital role in protecting shoots by preventing iron overaccumulation and toxicity. Meanwhile, its related proteins, BTS-LIKE1 and 2 (BTSL1/2), operate mainly in the roots to downregulate iron-deficiency responses. A group of transcription factors known as bHLH IVc acts as the central hub, interacting with these proteins to bridge the signaling gap between the roots and the aerial tissues.

The findings are significant because they solve a long-standing mystery regarding systemic iron signaling across a plant's biomass. By using Arabidopsis thaliana as a model, the researchers demonstrated that without these regulatory safeguards, plants suffer from leaf chlorosis and sterility due to oxidative stress. Lead researcher Liang Gang noted that identifying the bHLH IVc group as a mediator allows for a better understanding of how plants precisely balance nutrient uptake with metabolic needs, which could eventually inform more resilient crop development.

For more details, read the research news article on the CAS website.