A Phelipanche ramosa KAI2 protein perceives strigolactones and isothiocyanates enzymatically

• Published in: Plant communications Vol. 2; no. 5; p. 100166
• Main Authors: de Saint Germain, Alexandre, Jacobs, Anse, Brun, Guillaume, Pouvreau, Jean-Bernard, Braem, Lukas, Cornu, David, Clavé, Guillaume, Baudu, Emmanuelle, Steinmetz, Vincent, Servajean, Vincent, Wicke, Susann, Gevaert, Kris, Simier, Philippe, Goormachtig, Sofie, Delavault, Philippe, Boyer, François-Didier
• Format: Journal Article
• Language: English
• Published: China Elsevier Inc 13.09.2021; Cell Press; Elsevier
• Subjects: Amino Acid Sequence; bioactive properties; biological control; Central European region; Chemical Sciences; enzyme activity; Europe; evolution; Heterocyclic Compounds, 3-Ring - metabolism; Hydrolases - chemistry; Hydrolases - genetics; Hydrolases - metabolism; hypersensitivity; isothiocyanates; Isothiocyanates - metabolism; Lactones - metabolism; Life Sciences; Organic chemistry; Orobanchaceae - genetics; Orobanchaceae - metabolism; Orobanche ramosa; Phelipanche ramosa; Phylogeny; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Weeds - genetics; Plant Weeds - metabolism; receptor; seed germination; seed germination stimulant; Sequence Alignment; strigolactones; weeds; α/β-hydrolase; Europe; Central European region; isothiocyanates; α/β-hydrolase; receptor; Phelipanche ramosa; seed germination stimulant; strigolactones; a/b-hydrolase
• ISSN: 2590-3462; 2590-3462
• DOI: 10.1016/j.xplc.2021.100166

Phelipanche ramosa is an obligate root-parasitic weed that threatens major crops in central Europe. In order to germinate, it must perceive various structurally divergent host-exuded signals, including isothiocyanates (ITCs) and strigolactones (SLs). However, the receptors involved are still uncharacterized. Here, we identify five putative SL receptors in P. ramosa and show that PrKAI2d3 is involved in the stimulation of seed germination. We demonstrate the high plasticity of PrKAI2d3, which allows it to interact with different chemicals, including ITCs. The SL perception mechanism of PrKAI2d3 is similar to that of endogenous SLs in non-parasitic plants. We provide evidence that PrKAI2d3 enzymatic activity confers hypersensitivity to SLs. Additionally, we demonstrate that methylbutenolide-OH binds PrKAI2d3 and stimulates P. ramosa germination with bioactivity comparable to that of ITCs. This study demonstrates that P. ramosa has extended its signal perception system during evolution, a fact that should be considered for the development of specific and efficient biocontrol methods. Phelipanche ramosa is an obligate root-parasitic weed that threatens major crops in central Europe. This study reports the identification of a strigolactone receptor in P. ramosa, PrKAI2d3, that is involved in the stimulation of seed germination. The high plasticity of PrKAI2d3 allows it to interact with different chemicals, including isothiocyanates and methylbutenolide-OH.