Science Advances [SOPhy]

Abstract :

Strigolactones exhibit dual functionality as regulators of plant architecture and signaling molecules in the rhizosphere. The important model crop rice exudes a blend of different strigolactones from its roots. Here, we identify the inaugural noncanonical strigolactone, 4-oxo-methyl carlactonoate (4-oxo-MeCLA), in rice root exudate. Comprehensive, cross-species coexpression analysis allowed us to identify a cytochrome P450, OsCYP706C2, and two methyl transferases as candidate enzymes for this noncanonical rice strigolactone biosynthetic pathway. Heterologous expression in yeast and Nicotiana benthamiana indeed demonstrated the role of these enzymes in the biosynthesis of 4-oxo-MeCLA, which, expectedly, is derived from carlactone as substrate. The oscyp706c2 mutants do not exhibit a tillering phenotype but do have delayed mycorrhizal colonization and altered root phenotype. This work sheds light onto the intricate complexity of strigolactone biosynthesis in rice and delineates its role in symbiosis and development.

Graphical Abstract:

Reference :

OsCYP706C2 diverts rice strigolactone biosynthesis to a noncanonical pathway branch

Changsheng Li, Imran Haider, Jian You Wang, Pierre Quinodoz, Hernando G. Suarez Duran, Lucía Reyes, Méndez Robin Horber, Valentina Fiorilli, Cristina Votta, Luisa Lanfranco, Samara M. Correia de Lemos, Lucile Jouffroy, Baptiste Moegle, Laurence Miesch, Alain De Mesmaeker, Marnix H. Medema, Salim Al-Babili, Lemeng Dong, and Harro J. Bouwmeester

Science Advances, 28 Aug 2024, Vol 10, Issue 35; DOI: 10.1126/sciadv.adq3942

Contact :

Laurence Miesch, équipe SOPhy, Institut de Chimie de Strasbourg (UMR 7177).