Synthesis of photoaffinity probe based on the leaf-opening factor from genus Albizzia

The circadian rhythmic leaf-movements in legumes, called nyctinasty, are regulated by a pair of leaf-closing and -opening factors. Recent fluorescence studies revealed that cis-p-coumaroylagmatine (1), the leaf-opening factor from genus Albizzia, specifically bound to motor cells in a joint of leaf and stem. In order to identify the receptor protein, which is expected to be involved in the plasma membrane of the cell, we designed and synthesized a photoaffinity probe (2), containing a photoreactive azide group on the aromatic ring and FLAG segment as a peptide antigen for immunoprecipitation.