Abstract: Through transcriptome sequencing and differential expression gene analysis of Pleurotus pulmonarius samples at different developmental stages induced by low temperature in the previous study, it was found that the gene with ID Cluster-6377.64510 (named as PpFBD1) was highly expressed at the prophase of primordium formation. To further understand and analyze its expression characteristics and functions, the full-length cDNA sequences of PpFBD1 was cloned from Pleurotus pulmonarius by RT-PCR method with the specific primers designed based on transcriptome data. The PpFBD1 was composed of 342 nucleotides that encode a protein consisted of 113 amino acids. The relative molecular weight of this protein is about 11 ku. Phylogenetic tree analysis showed that the protein encoded by PpFBD1 had the closest relationship with hydrophobin1 of Pleurotus ostreatus. GO functional analysis showed that the PpFBD1 mainly involved in the synthesis of fungal cell walls. Fluorescence quantitative RT-PCR detection found that the expression of the gene was the highest in the phase of mycelium recovery to room temperature after induction at low temperature. It suggested that the gene may be involved in the regulation of primordium morphogenesis in Pleurotus pulmonarius. The results of this study provided a reference for elucidating the formation mechanism of the primordium of Pleurotus pulmonarius.

Key words: Pleurotus pulmonarius, PpFBD1, gene cloning, sequence analysis, expression analysis