Ding Yi, Lesterps Zélie, Gasciolli Virginie, Fuchs Anne-Laure, Gaston Mégane, Medioni Lauréna, de-Regibus Annélie, Remblière Céline, Vicédo Céline, Bensmihen Sandra, Bono Jean Jacques, Cullimore Julie, Reyt Guilhem, Dalmais Marion, Saffray Christine, Mazeau Solène, Bendahmane Abdelhafid, Sibout Richard, Vandenbussche Michiel, Rouster Jacques, Wang Tongming, He Guanghua, Masselin Arnaud, Cottaz Sylvain, Fort Sébastien, Lefebvre Benoit
Laboratory of Plant-Microbe-Environment Interactions (LIPME), Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France.
Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), Gif sur Yvette, France.
Nat Commun. 2025 Jul 1;16(1):5999. doi: 10.1038/s41467-025-60717-1.
Lipo-chitooligosaccharides (LCO) and short-chain chitooligosaccharides (CO) are produced by arbuscular mycorrhizal fungi (AMF) and activate the plant symbiosis signalling pathway, which is essential for mycorrhiza formation. High-affinity LCO receptors belonging to the LysM receptor-like kinase (LysM-RLK) phylogenetic group LYR-IA play a role in AM establishment, but it is unclear which proteins are the plant high-affinity short-chain CO receptors. Here we studied members of the uncharacterized LYR-IB group, and found that they show high affinity for LCO, short- and long-chain CO, and play a complementary role with the LYR-IA receptors for AM establishment. While LYR-IB knock out mutants had a reduced AMF colonization in several species, constitutive/ectopic expression in wheat increased AMF colonization. LYR-IB function is conserved in all tested angiosperms, but in most japonica rice a deletion creates a frameshift in the gene, explaining differences in AM phenotypes between rice and other monocot single LYR-IA mutants. In conclusion, we identified a class of LysM-RLK receptors in angiosperms with unique biochemical properties and a role in both LCO and CO perception for AM establishment.
脂壳寡糖（LCO）和短链壳寡糖（CO）由丛枝菌根真菌（AMF）产生，并激活植物共生信号通路，这对菌根形成至关重要。属于赖氨酸基序受体样激酶（LysM-RLK）系统发育组LYR-IA的高亲和力LCO受体在丛枝菌根建立过程中发挥作用，但尚不清楚哪些蛋白是植物高亲和力短链CO受体。在此，我们研究了未表征的LYR-IB组的成员，发现它们对LCO、短链和长链CO均表现出高亲和力，并在丛枝菌根建立过程中与LYR-IA受体发挥互补作用。虽然LYR-IB基因敲除突变体在多个物种中的丛枝菌根真菌定殖减少，但在小麦中的组成型/异位表达增加了丛枝菌根真菌定殖。LYR-IB功能在所有测试的被子植物中均保守，但在大多数粳稻中，一个缺失导致该基因发生移码突变，这解释了水稻与其他单子叶植物单LYR-IA突变体在丛枝菌根表型上的差异。总之，我们在被子植物中鉴定出一类具有独特生化特性且在丛枝菌根建立过程中对LCO和CO感知均起作用的LysM-RLK受体。
