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Crystal structure of Arabidopsis DWARF14-LIKE2 (DLK2) reveals a distinct substrate binding pocket architecture.

ABSTRACT: In Arabidopsis thaliana, the Sigma factor B regulator RsbQ-like family of α/β hydrolases contains the strigolactone (SL) receptor DWARF14 (AtD14), the karrikin receptor KARRIKIN INSENSITIVE2 (AtKAI2), and DWARF14-LIKE2 (AtDLK2), a protein of unknown function. Despite very similar protein folds, AtD14 and AtKAI2 differ in size and architecture of their ligand binding pockets, influencing their substrate specificity. We present the 1.5 Å crystal structure of AtDLK2, revealing the smallest ligand binding pocket in the protein family, bordered by two unique glycine residues. We identified a gatekeeper residue in the protein's lid domain and present a pyrrolo-quinoline-dione compound that inhibits AtDLK2's enzymatic activity.

SUBMITTER: Burger M

PROVIDER: S-EPMC9470386 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Crystal structure of <i>Arabidopsis</i> DWARF14-LIKE2 (DLK2) reveals a distinct substrate binding pocket architecture.

Bürger Marco M Honda Kaori K Kondoh Yasumitsu Y Hong Sharon S Watanabe Nobumoto N Osada Hiroyuki H Chory Joanne J

Plant direct 20220913 9

In <i>Arabidopsis thaliana</i>, the Sigma factor B regulator RsbQ-like family of α/β hydrolases contains the strigolactone (SL) receptor DWARF14 (AtD14), the karrikin receptor KARRIKIN INSENSITIVE2 (AtKAI2), and DWARF14-LIKE2 (AtDLK2), a protein of unknown function. Despite very similar protein folds, AtD14 and AtKAI2 differ in size and architecture of their ligand binding pockets, influencing their substrate specificity. We present the 1.5 Å crystal structure of AtDLK2, revealing the smallest l ...[more]

PMID: 36172078

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