Phylogenetic Relationships of Ramaria Species Based on Mitochondrial
Genome Analysis
Abstract
Ramaria has been a remarkable taxon throughout the history of
macrofungi. However, there is a lack of information on these macrofungi.
This study determined the order of nucleotides in the mitochondrial
genomes (mitogenomes) of three Ramaria species, followed by a detailed
investigation of the obtained genetic information. Circular mitogenomes
of Ramaria brunnecliacina, R. ichnusensis, and R. flavescens had sizes
of 78,960, 61,851, and 81,282 bp, respectively. The genomes exhibited
variations in genetic content, gene length, tRNA, and codon usage.
Ramaria mitogenomes demonstrated variable evolutionary rates across
several protein-coding genes. Results revealed significant gene
rearrangements in Ramaria mitogenomes, including gene displacement and
tRNA duplication. Bayesian inference and maximum likelihood methods,
yielded well-supported phylogenetic trees for Basidiomycota.
Phylogenetic analysis, using a comprehensive collection of conserved
mitochondrial proteins, yielded a strong and reliable phylogenetic tree
for Basidiomycetes, which clarified the evolutionary connections between
Ramaria and other Basidiomycetes members. R. brunnecliacina and R.
flavescens were identified as closely related species. Species of
Ramaria, a paraphyletic group, exhibited a close genetic relationship
with other species belonging to the subclass Phallomycetidae. This study
presents a basic structure for understanding the evolutionary dynamics,
genetic makeup, and taxonomy categorization of this significant fungal
community.