Genetic linkage map and expression analysis of genes expressed in the lamellae of the edible basidiomycete Pleurotus ostreatus

Pleurotus ostreatus is an industrially cultivated basidiomycete with nutritional and environmental applications. Its genome contains 35 Mbp organized in 11 chromosomes. There is currently available a genetic linkage map based predominantly on anonymous molecular markers complemented with the mapping of QTLs controlling growth rate and industrial productivity. To increase the saturation of the existing linkage maps, we have identified and mapped 82 genes expressed in the lamellae. Their manual annotation revealed that 34.1% of the lamellae-expressed and 71.5% of the lamellae-specific genes correspond to previously unknown sequences or to hypothetical proteins without a clearly established function. Furthermore, the expression pattern of some genes provides an experimental basis for studying gene regulation during the change from vegetative to reproductive growth. Finally, the identification of various differentially regulated genes involved in protein metabolism suggests the relevance of these processes in fruit body formation and maturation.