The Composition of the Tripartite Symbiosis in Cladonia uncialis: A Genomic Dissection of the Fungal, Photobiont Genomes and Microbial Community
As symbiotic complexes formed through the association of bacteria or algae with fungi, lichens exhibit exceptional adaptability to extreme environments and function as pioneer species in rocky habitat ecological succession. The absence of chromosome-level genomes has constrained investigations into lichen adaptive evolution, while functional contributions of symbiotic bacterial communities remain inadequately explored. This study presents the chromosome-level genome assembly of the mycobiont Cladonia uncialis, comprising 28 chromosomes with a total size of 43.49 Mb, generated through integrated PacBio HiFi and Hi-C methodologies. We characterized the symbiotic microbiota using integrated short and long-read sequencing and constructed 31 metagenome-assembled genomes. The community was dominated by Ascomycota (41.16%), Proteobacteria (17.61%), and Bacteroidota (14.20%). Long-read sequencing significantly enhanced detection sensitivity for low-abundance taxa. This study provides essential genomic resources and c