5DNW

Crystal structure of KAI2-like protein from Striga (apo state 1)

Summary for 5DNW

• Entry DOI: 10.2210/pdb5dnw/pdb
• Related: 5DNU 5DNV
• Descriptor: ShKAI2iB, FORMIC ACID, 1,2-ETHANEDIOL, ... (5 entities in total)
• Functional Keywords: kai2 karrikin striga, hydrolase
• Biological source: Striga hermonthica
• Total number of polymer chains: 1
• Total formula weight: 30759.69

Authors

Xu, Y.,Miyakawa, T.,Nakamura, A.,Tanokura, M. (deposition date: 2015-09-10, release date: 2016-08-17, Last modification date: 2023-11-08)

Primary citation

Xu, Y.,Miyakawa, T.,Nakamura, H.,Nakamura, A.,Imamura, Y.,Asami, T.,Tanokura, M.
Structural basis of unique ligand specificity of KAI2-like protein from parasitic weed Striga hermonthica
Sci Rep, 6:31386-31386, 2016

PubMed Abstract: The perception of two plant germination inducers, karrikins and strigolactones, are mediated by the proteins KAI2 and D14. Recently, KAI2-type proteins from parasitic weeds, which are possibly related to seed germination induced by strigolactone, have been classified into three clades characterized by different responses to karrikin/strigolactone. Here we characterized a karrikin-binding protein in Striga (ShKAI2iB) that belongs to intermediate-evolving KAI2 and provided the structural bases for its karrikin-binding specificity. Binding assays showed that ShKAI2iB bound karrikins but not strigolactone, differing from other KAI2 and D14. The crystal structures of ShKAI2iB and ShKAI2iB-karrikin complex revealed obvious structural differences in a helix located at the entry of its ligand-binding cavity. This results in a smaller closed pocket, which is also the major cause of ShKAI2iB's specificity of binding karrikin. Our structural study also revealed that a few non-conserved amino acids led to the distinct ligand-binding profile of ShKAI2iB, suggesting that the evolution of KAI2 resulted in its diverse functions.

PubMed: 27507097
DOI: 10.1038/srep31386

Experimental method

X-RAY DIFFRACTION (2.02 Å)