3OZI

Crystal structure of the TIR domain from the flax disease resistance protein L6

Summary for 3OZI

• Entry DOI: 10.2210/pdb3ozi/pdb
• Descriptor: L6tr, COBALT (II) ION (3 entities in total)
• Functional Keywords: plant tir domain, signal transduction, plant protein
• Biological source: Linum usitatissimum (Flax)
• Total number of polymer chains: 2
• Total formula weight: 46913.31

Authors

Ve, T.,Bernoux, M.,Williams, S.,Valkov, E.,Warren, C.,Hatters, D.,Ellis, J.G.,Dodds, P.N.,Kobe, B. (deposition date: 2010-09-25, release date: 2011-04-27, Last modification date: 2023-11-01)

Primary citation

Bernoux, M.,Ve, T.,Williams, S.,Warren, C.,Hatters, D.,Valkov, E.,Zhang, X.,Ellis, J.G.,Kobe, B.,Dodds, P.N.
Structural and Functional Analysis of a Plant Resistance Protein TIR Domain Reveals Interfaces for Self-Association, Signaling, and Autoregulation.
Cell Host Microbe, 9:200-211, 2011

PubMed Abstract: The Toll/interleukin-1 receptor (TIR) domain occurs in animal and plant immune receptors. In the animal Toll-like receptors, homodimerization of the intracellular TIR domain is required for initiation of signaling cascades leading to innate immunity. By contrast, the role of the TIR domain in cytoplasmic nucleotide-binding/leucine-rich repeat (NB-LRR) plant immune resistance proteins is poorly understood. L6 is a TIR-NB-LRR resistance protein from flax (Linum usitatissimum) that confers resistance to the flax rust phytopathogenic fungus (Melampsora lini). We determine the crystal structure of the L6 TIR domain and show that, although dispensable for pathogenic effector protein recognition, the TIR domain alone is both necessary and sufficient for L6 immune signaling. We demonstrate that the L6 TIR domain self-associates, most likely forming a homodimer. Analysis of the structure combined with site-directed mutagenesis suggests that self-association is a requirement for immune signaling and reveals distinct surface regions involved in self-association, signaling, and autoregulation.

PubMed: 21402359
DOI: 10.1016/j.chom.2011.02.009

Experimental method

X-RAY DIFFRACTION (2.3 Å)