Convergent evolution of NFP- facilitated root nodule symbiosis

• 成果类型: Article
• 署名作者: Finegan, Christina; Kates, Heather R.; Guralnick, Robert P.; Soltis, Pamela S.; Resende Jr, Marcio F. R.; Ane, Jean-Michel; Kirst, Matias; Folk, Ryan A.; Soltis, Douglas E.
• 署名单位: State University System of Florida; University of Florida; State University System of Florida; University of Florida; State University System of Florida; University of Florida; State University System of Florida; University of Florida; State University System of Florida; University of Florida; State University System of Florida; University of Florida; University of Wisconsin System; University of Wisconsin Madison; University of Wisconsin System; University of Wisconsin Madison; Mississippi State University; State University System of Florida; University of Florida
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-10075
• DOI: 10.1073/pnas.2424902122
• 发表日期: 2025-09-16
• 关键词: medicago-truncatula; arbuscular mycorrhiza; nitrogen-fixation; duplications; legume; specificity; parasponia; rhizobia; insights; inputs

摘要

The origin and phylogenetic distribution of symbiotic associations between nodulating angiosperms and nitrogen- fixing bacteria have long intrigued biologists. Recent comparative evolutionary analyses have yielded alternative hypotheses: a multistep pathway of independent gains and losses of root nodule symbiosis vs. a single gain followed by numerous losses. A detailed reconstruction of the history of genes involved in signaling between nitrogen- fixing bacteria and potential hosts, particularly lipo- chitooligosaccharide (LCO) signaling, is needed to distinguish between these hypotheses. LCO recognition by plants involves the Nod Factor Perception (NFP) gene family; in the legume model Medicago truncatula (Fabales), MtNFP is essential for establishing rhizobial symbiosis. Here, we document convergent evolution of NFP, indicating multiple origins of LCO- driven symbiosis. In contrast to previous models that explain the recruitment of NFP via a single duplication in the ancestor of the nitrogen- fixing clade, our phylogenomic and synteny results suggest this duplication does not span the entire clade. Tandem duplication in a common ancestor of Cucurbitales and Rosales resulted in the NFP1 and NFP2 groups. In contrast, the phylogenetically closest paralog of MtNFP is MtLYR1, located on a different chromosome within a large syntenic block. All available data indicate that a large- scale duplication resulted in MtNFP and MtLYR1, likely corresponding to a whole- genome duplication in an ancestor of subfamily Papilionoideae of Fabaceae. We show that MtNFP and the NFP2- like group are not orthologous, indicating multiple independent gains of NFP- based LCO signaling. This molecular convergence provides a possible mechanism for multiple gains of root nodule symbiosis across the nitrogen- fixing clade.