6I8H

Structure of the plant immune signaling node EDS1 (enhanced disease susceptibility 1) in complex with nanobody ENB15

Summary for 6I8H

• Entry DOI: 10.2210/pdb6i8h/pdb
• Descriptor: Protein EDS1L, EDS1-specific nanobody (2 entities in total)
• Functional Keywords: enhanced disease susceptibility 1, plant innate immune system, alpha/beta hydrolase fold, nanobody, immune system
• Biological source: Arabidopsis thaliana (Mouse-ear cress); More
• Total number of polymer chains: 2
• Total formula weight: 87711.64

Authors

Niefind, K.,Voss, M.,Toelzer, C. (deposition date: 2018-11-20, release date: 2019-10-02, Last modification date: 2024-01-24)

Primary citation

Voss, M.,Toelzer, C.,Bhandari, D.D.,Parker, J.E.,Niefind, K.
Arabidopsis immunity regulator EDS1 in a PAD4/SAG101-unbound form is a monomer with an inherently inactive conformation.
J.Struct.Biol., 208:107390-107390, 2019

PubMed Abstract: In plant innate immunity, enhanced disease susceptibility 1 (EDS1) integrates all pathogen-induced signals transmitted by TIR-type NLR receptors. Driven by an N-terminal α/β-hydrolase-fold domain with a protruding interaction helix, EDS1 assembles with two homologs, phytoalexin-deficient 4 (PAD4) and senescence-associated gene 101 (SAG101). The resulting heterodimers are critical for EDS1 function and structurally well characterized. Here, we resolve solution and crystal structures of unbound Arabidopsis thaliana EDS1 (AtEDS1) using nanobodies for crystallization. These structures, together with gel filtration and immunoprecipitation data, show that PAD4/SAG101-unbound AtEDS1 is stable as a monomer and does not form the homodimers recorded in public databases. Its PAD4/SAG101 anchoring helix is disordered unless engaged in protein/protein interactions. As in the complex with SAG101, monomeric AtEDS1 has a substrate-inaccessible esterase triad with a blocked oxyanion hole and without space for a covalent acyl intermediate. These new structures suggest that the AtEDS1 monomer represents an inactive or pre-activated ground state.

PubMed: 31550533
DOI: 10.1016/j.jsb.2019.09.007

Experimental method

X-RAY DIFFRACTION (3.682 Å)