Transcriptome Analysis Of The Budding Mushroom Agaricus Bisporus Fruiting At Different Stages

Agaricus bisporus belongs to large basidiomycete fungi with special secondary consanguinity combination way,which is one of the most commercially cultivated mushroom in the world,has an important economic value.RNA-Sequencing(RNA-Seq)is one of the next-generation sequencing(NGS)techniques with the characteristics of high-throughput,and providing a powerful technology platform for identigying genes related to fruit-body development.To better understand the gene expression changes of fruiting body development in Agaricus bisporus,we adopt RNA-Seq sequencing to research the development of fruiting body of Agaricus bisporus at the pinhead stage,closed cup stage and flat 2 stage.The main results were as follows:(1)We obtained more than 14413011 high quality reads in each library.And 10438 transcripts,longer than 150 bp,were got by mapping.The total length of unigene was14775783,and the average length of unigene was 1415 bp,N50 length of unigene was 2195 bp.(2)Unigene sequences were aligned to reference genome,then 57.87% of transcript was mapped to the genome.A total of 5798 differential expressed genes were identified in the different stage of fruiting body.Among them,837 differentially expressed genes were divided into 98 pathway.(3)Differentially expressed genes in the different stage of fruiting body of Agaricus bisporus were conduct GO function enrichment and Pathway analysis.The Gene Ontology classification showed that,the differentially expressed genes were mostly enriched in binding,catalytic molecular functions and metabolic process biological pathway.All the transcripts associated with developmental and reproduction process were up-regulated,which implicated that the increased gene expression lever can facilitate the cell differentiation from vegetative mycelium to generative mycelium.Pathway analyses revealed that a large number of differential genes mainly were enriched in nucleotide metabolism,carbohydrate metabolism,energy metabolism,lipid metabolism and amino acid metabolism,which contains a large number of enzymes,proteins,such as kinase protein,GTP binding protein,sinnal receptor protein and some transcription factor.Suggesting that the fruiting body development of Agaricus bisporus requires a series of metabolic reactions and various types of transcription factor gene expression regulation.(4)Two key genes and eight candidate genes with development process were analyzed by real-time PCR.Results showed that gene148258 and gene223689 were highly expressed from button stage to cup1 stage and reached the peak in the cup 2 stage,and with similar expression patterns.Which may be relative to sexual reproduction.Candidate gene for Frt1-like protein?fungal hydrophobic protein and hsp70 were highly expressed throughout the growth;Genes for pkinase protein and serine threonine protein phosphatase were highly expressed from button stage to cup2 stage and reached the peak in the cup2 stage,which may be related to fruiting.Genes for translation elongation factor was highly expressed in cup2 stage during the whole stage,which suggesting their functions in adavenced cell elongation.Gene for tyrosinase was low expressed in different developmental stage other than button stage,implying its relevant to fruiting primordium differentiation.Gene for laccase was highly expression from fruit-body pinhead to cup2 stage,which indicating it may be associated with fruit body differentiation and maturation.All these genes may play important roles in fruit-body formation,which need to be further study to illustrate the molecular mechanism.