Pleurotus pulmonarius, a member of the Pleurotaceae family
in Basidiomycota, is an edible, economically important mushroom
in most Asian countries. In this study, the complete
mitochondrial genomes (mtDNA) of three P. pulmonarius
strains – two monokaryotic commercial (J1-13 and ZA3) and
one wild (X1-15) – were sequenced and analyzed. In ZA3 and
X1-15, the mtDNA molecule was found to be a single circle of
68,305 bp and 73,435 bp, respectively. Both strains contain 14
core protein-coding genes and two ribosomal RNA (rRNA)
subunit genes. The ZA3 strain has 22 transfer RNA (tRNA)
genes and nine introns: eight in cytochrome c oxidase subunit
1 (cox1), and one in the rRNA large subunit (rnl). Monokaryotic
J1-13 and ZA3 mtDNAs were found to be similar
in their structure. However, the wild strain X1-15 contains
25 tRNA genes and only seven introns in cox1. Open reading
frames (ORFs) of ZA3/J1-13 and X1-15 encode LAGLIDADG,
ribosomal protein S3, and DNA polymerase II. In addition,
mtDNA inheritance in J1-13, ZA3, and X1-15 was also studied.
Results
showed that the mtDNA inheritance pattern was uniparental
and closely related to dikaryotic hyphal location with
respect to the parent. Results also show that mtDNA inheritance
is influenced by both the parental nuclear genome and
mitogenome in the zone of contact between two compatible
parents. In summary, this analysis provides valuable information
and a basis for further studies to improve our understanding
of the inheritance of fungal mtDNA.