Color Genetic Characteristics And Transcriptome Analysis For Hypsizygus Marmoreus

Hypsizygus marmoreus is one of the main well-known edible mushrooms that has been realized industrial production. The color of H. marmoreus fruit body on the market can be divided into two broad categories, dust-color and white. But the white species has a longer planting period, weaker resistance, higher nutritional requirements and better environmental conditions. The color change of fruit body in H. marmoreus is also accompanied by other changes associated with its growing traits. This study aims to understand the mechanism of color formation in H. marmoreus and to find the color related genes and metabolic pathways, which can provide a reference for white mushroom breeding.Our group had found a white H. marmoreus strain which is a mutation of normal H. marmoreus in hybridization tests.The technology of differential gene expression analysis was used to find color related genes and their mechanism of action. The relationship between the two colors was identified by hybridization tests. The resaults could be categorized as the following 3 tips.1.The mutation was verified by use of Inter genicspacer 2 (IGS2) and the random amplified polymorphic DNA(RAPD) maker.The IGS2 sequences of the two strans is consistent and RAPD analysis showed that two strains’similarity coefficient was 100%, which successfully verified the white mutant.2.SIEF4076 (dust-color) and SIEF4074 (pure white) were selected for material to analysize fruit-body color and two method of hybridization was used.Two heterozygotes were received by protoplast monokaryogenesis method. The color of heterozygotes is dust and white, which indicated the white related gene can express stablely in hybridization by protoplast monokaryogenesis method. A total of 45 heterozygotes were received in monospore cross.There were 32 dust hybrid strains and 13 white hybrid strains. The segregation of dust to white was nearly 2.5:1.We speculated that white related gene can not express stablely in hybridization by monospore cross and the color related gene may not be only one.3. Using Hiseq2000 Genome Analyzer platform, a transcriptome containing mRNA of 4 samples including mycelium of SIEF4074 and SIEF4076 during color turning. Four samples were named B1, B2, W1 and W2. After carrying out cDNA sequencing, assembly, annotation and bioinformatics analysis. At last, we got a number of 24528 isogenes with the average length 2167 nt. The differentially expressed genes involved in B1 and B2, W2 and B2 were compared.Four differentially expressed genes were finded.they were cyclopentanone 1,2-monooxygenase, laccase 2, MFS general substrate transporter and cytochrome P450. We performed Clusters of Orthologous Groups of proteins (COG) functional classification, Gene Ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment of the differentially expressed genes. COG functional classification showed that differentially expressed genes were mainly involved in protein and DNA synthesis, amino acids and carbohydrate metabolic process. GO functional enrichment showed that most of the significantly changed genes were correlated to carbohydrate metabolic process, hydrolase activity and catalytic activity, pathway enrichment showed that there were 26 enrichment pathway, which include tryptophan metabolism pathways, mineral absorption pathways and so on.