Effect Of Blue-light On Endogenous Auxin And Effective Components Of Ganoderma Lucidum

To study the effect and mechanism of light quality on Ganoderma lucidum,and provide a theoretical basis for G.lucidum cultivation,the endogenous auxin content and metabolizing enzymes activity,active substance content and blue-light receptor of G.lucidum were investigated.According to the morphological changes in the growth process of G.lucidum fruiting body,the morphogenesis was divided into four stages,build a shed for blue transparent film with wavelength of 320-560 nm,contrast is the G.lucidum growth under natural conditions.The content change of auxin and effective medicinal ingredients was detected by HPLC and UV spectrophotometry.Genome information of G.lucidum has been obtained to cloned the key enzyme genes in auxin biosynthesis pathway and blue-light receptor genes of G.lucidum,and using real-time PCR to understand their spatial and temporal expression.Blue light was influence on the content of auxin,polysaccharide and triterpene acids of G.lucidum.The dry weight by the blue light was higher than that of the control during the growth and development G.lucidum.The contend of auxin in the second stage was the highest,the control group was significantly higher than blue light treatment.The content of total polysaccharide has no significant difference in four stage,and there was no significant difference between the two treatments.The ganoderic acids A as the quality assessment standard for G.lucidum was the highest triterpene acids in the fruiting body of G.lucidum.The content of 3 kinds of ganoderenic acids,namely,ganoderenic acids A,ganoderenic acids D and ganoderenic acids B were extremely low in different growth stages of G.lucidum,the content of 7 kinds of ganoderic acids in the third stage was the largest,and decreased significantly in the fourth stage.In the third stage,7 kinds of ganoderic acids under the blue light were all higher than the control group.In this study,KAAS automatic annotation server was used to predicted the whole genome metabolic map of G.lucidum,screened 13 sequences related to IAA synthesis,including 2 GlTaml,1 GlDDC,1 GlAOC1,6 GIAldh,and 3 GlAMI.The results showed that there was a complete Tam pathway,and may had IPA pathway and IAM pathway in G.lucidum.GlWC-1 and GlWC-2 were homologue with blue light photoreceptor NcWC-1 and NcWC-2 of Neurospora crassa.The deduced amino acid sequence of Glwc-1 contains the similar function domains as NcWC-1 including LOV,PAS B,PAS C and PAC domains.And the deduced amino acid sequence of Glwc-2 contains PAS domain and GATA-type zinc finger(Znf)domain as well as NcWC-2.Phylogenetic analysis based on fungal WC-1 and WC-2 supported GlWC-1 and GlWC-2 were blue light receptor.Finally,the relative expression level of each gene in auxin synthesis pathway was detected by Real-time qPCR.The results showed that all of the 13 genes identified were expressed in four period,in addition to ami(GL29633-R1),the relative expression of the other 12 genes was highest in the second period,and significantly higher than the other three periods,this is consistent with the change of auxin content in G.lucidum.This is consistent with the trend of IAA content in the fruiting bodies of G.lucidum.Therefore,we speculate that in the second period,the growth and metabolism of G.lucidum are strong,is the active life period.The gene expression after blue light treatment is very different from that of natural light,which shows that blue light has some effect on the synthesis of IAA.The expression of Glwc-1 and Glwc-2 indicating that they may play an important role in the primordium differentiation process of G.lucidum,and the external blue light stimulation may increased the expression of Glwc-1 and Glwc-2.