Independent signalling cues underpin arbuscular mycorrhizal symbiosis and large lateral root induction in rice

• Published in: The New phytologist Vol. 217; no. 2; pp. 552 - 557
• Main Authors: Chiu, Chai Hao, Choi, Jeongmin, Paszkowski, Uta
• Format: Journal Article
• Language: English
• Published: England New Phytologist Trust 01.01.2018; Wiley Subscription Services, Inc
• Subjects: arbuscular mycorrhizal (AM) symbiosis; Arbuscular mycorrhizas; Chitin; Colonization; Cues; Cultivars; D14L; Deletion mutant; elicitors; Fungi; Glomeromycota - physiology; Hydrolase; Inoculation; lateral root; Models, Biological; mutants; Mutation - genetics; Mycorrhizae - physiology; mycorrhizal fungi; Oryza - microbiology; Oryza - physiology; Perception; Plant Proteins - metabolism; Rapid report; receptor kinase; Receptors; Rhizophagus irregularis; rice; rice (Oryza sativa); root system architecture; rooting; Signal Transduction; Signaling; signalling; Symbionts; Symbiosis; Symbiosis - physiology; Transcription; transcription (genetics); vesicular arbuscular mycorrhizae; arbuscular mycorrhizal (AM) symbiosis; rice (Oryza sativa); D14L; lateral root; root system architecture; signalling; Rhizophagus irregularis; receptor kinase
• ISSN: 0028-646X; 1469-8137; 1469-8137
• DOI: 10.1111/nph.14936

Perception of arbuscular mycorrhizal fungi (AMF) triggers distinct plant signalling responses for parallel establishment of symbiosis and induction of lateral root formation. Rice receptor kinase CHITIN ELICITOR RECEPTOR KINASE 1 (CERK1) and α/β-fold hydrolase DWARF14-LIKE (D14L) are involved in pre-symbiotic fungal perception. After 6wk post-inoculation with Rhizophagus irregularis, root developmental responses, fungal colonization and transcriptional responses were monitored in two independent cerk1 null mutants; a deletion mutant lacking D14L, and with D14L complemented as well as their respective wild-type cultivars (cv Nipponbare and Nihonmasari). Here we show that although essential for symbiosis, D14L is dispensable for AMF-induced root architectural modulation, which conversely relies on CERK1. Our results demonstrate uncoupling of symbiosis and the symbiotic root developmental signalling during pre-symbiosis with CERK1 required for AMF-induced root architectural changes.