2018/06/29 by Fay‐Wei Li, Paul Brouwer, Lorenzo Carretero‐Paulet +39 · 546 citations
Biochemistry, Genetics and Molecular Biology · Agricultural and Biological Sciences · #Plant and Fungal Species Descriptions #Biological Control of Invasive Species #Plant Diversity and Evolution #Azolla #Biology #Fern #Symbiosis #Genome #Botany #Horizontal gene transfer #Plant evolution #Gene #Evolutionary biology #Genetics #Bacteria
paper · pdf · doi:10.1038/s41477-018-0188-8
published in Nature Plants 4(7), 460-472 (Nature Portfolio)
openalex publication_date 2018/06/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Abstract Ferns are the closest sister group to all seed plants, yet little is known about their genomes other than that they are generally colossal. Here, we report on the genomes of Azolla filiculoides and Salvinia cucullata (Salviniales) and present evidence for episodic whole-genome duplication in ferns—one at the base of ‘core leptosporangiates’ and one specific to Azolla . One fern-specific gene that we identified, recently shown to confer high insect resistance, seems to have been derived from bacteria through horizontal gene transfer. Azolla coexists in a unique symbiosis with N 2 -fixing cyanobacteria, and we demonstrate a clear pattern of cospeciation between the two partners. Furthermore, the Azolla genome lacks genes that are common to arbuscular mycorrhizal and root nodule symbioses, and we identify several putative transporter genes specific to Azolla –cyanobacterial symbiosis. These genomic resources will help in exploring the biotechnological potential of Azolla and address fundamental questions in the evolution of plant life.