ALI1 interacts with N-acyl homoserine lactone and is involved in the perception of the quorum sensing molecule

In this report, we investigated oxo-C14-HSL-interacting proteins in plants. We propose the AHL-Interacting Protein 1 (ALI1) (previously known as AtGalk2) as interacting protein for oxo-C14-HSL in Arabidopsis. We present here several levels of confirmation and suggest that ALI1 is required for the perception of oxo-C14-HSL in Arabidopsis. This is the first direct evidence of a plant protein interacting with a bacterial quorum sensing molecule. Overall design: Examination of Col-0 and ali1 mutant seedlings pretreated for three days with 6 µM oxo-C14-HSL or acetone control and subsequently elicited with 100 nM flg22. All treatments were performed in triplicates.