9VBV

Cryo-EM structure of a CARD1 ectodomain H197A/H199A/H222A mutant

Summary for 9VBV

• Entry DOI: 10.2210/pdb9vbv/pdb
• EMDB information: 64934
• Descriptor: Leucine-rich repeat receptor protein kinase HPCA1,Maltose/maltodextrin-binding periplasmic protein, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, beta-D-mannopyranose-(1-6)-beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (4 entities in total)
• Functional Keywords: leucine-rich repeat receptor-like kinase, signaling protein
• Biological source: Arabidopsis thaliana (thale cress); More
• Total number of polymer chains: 1
• Total formula weight: 101045.95

Authors

Fukuda, Y.,Ishihama, N.,Laohavisit, A. (deposition date: 2025-06-05, release date: 2026-04-08, Last modification date: 2026-06-03)

Primary citation

Ishihama, N.,Fukuda, Y.,Shirano, Y.,Fujimoto, K.J.,Takizawa, K.,Hiroyama, R.,Ito, H.,Nishimura, M.,Yanai, T.,Inoue, T.,Shirasu, K.,Laohavisit, A.
A copper-dependent redox-based hydrogen peroxide perception in plants.
Nat Commun, 17:-, 2026

PubMed Abstract: Redox-related molecules, such as quinones and reactive oxygen species (ROS), are important signaling molecules for all living organisms. A plant-specific leucine-rich repeat receptor-like kinase (LRR-RLK) CANNOT RESPOND TO DMBQ 1 (CARD1), also known as HYDROGEN-PEROXIDE-INDUCED Ca INCREASES (HPCA1), perceives both quinones and ROS, but the mechanism by which it distinguishes between these two types of signals remains unclear. Here, we determine the structure of the CARD1 ectodomain and uncover its unique features. Structural studies, coupled with genetics and biochemical analysis, demonstrate that previously identified unique cysteine residues are not essential for signal perception in CARD1. Interestingly, CARD1 harbors a copper ion on the surface of the ectodomain via histidine-coordination that is crucial for hydrogen peroxide signaling. Our work reports a unique copper-dependent redox perception in plants and provides insight into interactions between receptors and non-peptide stimuli during perception.

PubMed: 42151134
DOI: 10.1038/s41467-026-72573-8

Experimental method

ELECTRON MICROSCOPY (3.61 Å)