AtTrxh3, a Thioredoxin, Is Identified as an Abscisic AcidBinding Protein in .

Abscisic acid (ABA, ) is a plant hormone that regulates various plant physiological processes such as seed developing and stress responses. The ABA signaling system has been elucidated; binding of ABA with PYL proteins triggers ABA signaling. We have previously reported a new method to isolate a protein targeted with a bioactive small molecule using a biotin linker with alkyne and amino groups, a protein cross-linker, and a bioactive small molecule with an azido group (azido probe).

Identification of recombinant AtPYL2, an abscisic acid receptor, in E. coli using a substrate-derived bioactive small molecule, a biotin linker with alkyne and amino groups, and a protein cross-linker.

Target protein identification of bioactive small molecules is one of the most important research in forward chemical genetics. The affinity chromatography technique to use a resin bound with a small molecule is often used for identification of a target protein of a bioactive small molecule. Here we report a new method to isolate a protein targeted with a bioactive small molecule using a biotin linker with alkyne and amino groups, protein cross-linker containing disulfide bond, and a bioactive small molecule with an azido group (azido probe).

Novel biotin linker with alkyne and amino groups for chemical labelling of a target protein of a bioactive small molecule.

We synthesized a novel linker (1) with biotin, alkyne and amino groups for the identification of target proteins using a small molecule that contains an azide group (azide probe). The alkyne in the linker bound the azide probe via an azide-alkyne Huisgen cycloaddition. A protein cross-linker effectively bound the conjugate of the linker and an azide probe with a target protein.

Tandem photoaffinity labeling of a target protein using a linker with biotin, alkyne and benzophenone groups and a bioactive small molecule with an azide group.

A novel linker containing biotin, alkyne and benzophenone groups (1) was synthesized to identify target proteins using a small molecule probe. This small molecule probe contains an azide group (azide probe) that reacts with an alkyne in 1 via an azide-alkyne Huisgen cycloaddition. Cross-linking of benzophenone to the target protein formed a covalently bound complex consisting of the azide probe and the target protein via 1.