GSE168162
A mycorrhiza-associated receptor-like kinase with an ancient origin in the green lineage
Receptor-like kinases (RLKs) are key cell signalling components. The rice ARBUSCULAR RECEPTOR-LIKE KINASE 1 (OsARK1) functions during a stage post-arbuscule development in the arbuscular mycorrhizal (AM) association and belongs to an undefined subfamily of RLKs. Our phylogenetic analysis revealed that ARK1 has an ancient paralogue, ARK2. Single ark2 and ark1ark2 double mutants in rice showed a non-redundant AM symbiotic function for OsARK2. Global transcriptomics identified a set of genes co-regulated by the two RLKs suggesting OsARK1 and OsARK2 to orchestrate symbiosis in a common pathway. ARK lineage proteins harbour a newly identified SPARK domain in their extracellular regions which underwent parallel losses in ARK1 and ARK2 in monocots. This protein domain has ancient origins in the green lineage and defines additional overlooked groups of putative cell surface receptors Overall design: Four different genotypes (ark1-2,ark2,ark1ark2,wild type) of rice were subjected to mycorrhizal fungi R. irregularis. Ten biological replicates were generated for each genotype. To study the effects of mutants ark1 and ark2, the transcriptomes were analyzed against the wild type controls.