The Type III Effector NopM from Bradyrhizobium elkanii USDA61 Induces a Hypersensitive Response in Lotus japonicus Root Nodules.

ABSTRACT: Leguminous plants establish root nodule symbiosis, which is initiated by the recognition of rhizobial nodulation factors by plant receptor kinases. However, other factors, such as Type III effector proteins, also affect host specificity. We herein investigated the role of nodulation outer protein M (NopM), a Type III effector of Bradyrhizobium elkanii USDA61, in symbiosis with Lotus japonicus MG-20 and Lotus burttii. NopM, annotated as an E3 ubiquitin ligase, triggers an early senescence-like response, inducing brown nodules that hinder effective symbiosis. NopM shares structural features with E3 ubiquitin ligases derived from both pathogenic and symbiotic bacteria, including a leucine-rich-repeat and E3 ubiquitin ligase domain. The deletion of these domains or substitution of the cysteine

SUBMITTER: Ying C 

PROVIDER: S-EPMC12727206 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature