Transcriptome Analysis And Arsenic Speciation By HPLC-ICP-MS Of The Mycelium From Trametes Versicolor(l.)Lloyd Under Arsenic Stress

Trametes versicolor(L.)Lloyd,also known as Coriolis versicolor,Variegous coriolis versicolor,and Streptococcus discolata,belongs to Fungi phylum,basidiomycota,Poraceae,and streptococcus,and is a large wood mould fungus with important medicinal value.It has been recorded in The Chinese Pharmacopoeia(2020 edition): Trametes versicolor(L.)Lloyd has the effect of improving human immunity,protecting liver and fighting cancer.At present,researches on the pharmacology and efficacy of B.lucidum focus on the industrial application of laccase decolorization,but there are few reports on heavy metal enrichment,screening of germplasm resources with tolerance and detoxification of heavy metals.On the basis of the 10 strains collected and identified by our research group,the content of As in mycelium of 10 strains under arsenic(As)stress was detected by ICP-MS to screen As enrichment and tolerance strains.Through antioxidant activity detection,RNA-seq transcriptomic sequencing and HPLC-ICP-MS typing study in the target strain,changes in antioxidant stress enzymes activity,differences in expression of related regulatory genes,and changes in As typing were explored,so As to analyze the impact of As stress on the mycelia of B.yunnanum and the potential detoxification pathway of B.yunnanum to As.The material basis and transcriptional expression level related to As detoxification were emphasized,which provided the basis for further study on the mechanism of As detoxification,and provided the basis for further directional breeding of low enrichment varieties of As and efficient and safe production of E.odoratum.The results are as follows:(1)The tolerance of 10 Strains to As enrichment and the contents of seven trace elements were analyzed by ICP-MS under As III stress(80 mg/L).The results showed that the stress concentration inhibited the growth of 10 Strains of B.lucidum to a certain extent,and the order of mycelial inhibition rate was HN01>JL2>JL3>DB8>DB5>HN02>YUN5>YUN2>YUN1>DB4.Among the 10 strains,HN01 had the strongest resistance to 80 mg/L AsIII.The order of enrichment capacity was HN01>YUN2>JL3>DB8>DB5>DB4 >YUN1>YUN5>JL2>HN02.HN01 had the strongest enrichment capacity for 80 mg/L AsIII,and BCF value reached 6.7305.In addition,the addition of exogenous AsIII also had different effects on the contents of other 7 trace elements in B.lucidum strain,and the obvious change was that the addition of exogenous AsIII significantly reduced the enrichment of Pb by DB5.(2)The activity or content changes of four kinds of antioxidants in HN01 strain under As stress were analyzed by using a microplate analyzer,and these four enzymes were related to the antioxidant stress system.The results showed that compared with the blank group,the CONTENT of GSH in HN01 strain under As stress was significantly increased(P<0.05),while SOD,CAT and MDA had no significant differences(P>0.05),suggesting that As stress may induce the synthesis of GSH.Moreover,GSH plays an important role in alleviating the oxidative damage of As to the mycelia of B.lucidum.(3)Transcriptome and differentially expressed genes of HN01 mycelium under AsⅢstress were analyzed based on RNA-Seq sequencing technology.The results showed that698 differentially expressed genes were detected under As stress,of which 342 were upregulated and 356 down-regulated.Through GO functional annotation,we found that the differential genes were distributed in different biological functional regions,and were involved in biological attachment,signaling,organization or biosynthesis of cell components,biological regulation,response to stimuli,and detoxification respectively.Extracellular regions,polymer complexes,membrane lumens,supramolecular compounds and cell connections;Biological functions such as electron carrier activity,signal transduction activity,molecular transduction activity,molecular functional regulator and antioxidant activity.Through KEGG pathway analysis,Differentially expressed genes were mainly involved in starch and sucrose metabolism(9.39%),amino acid biosynthesis(9.39%),carbon metabolism(6.08%),mitogen-activated protein kinase signaling pathway-yeast(6.08%),meiotic yeast(5.52%),cysteine and methionine metabolism(5.52%)and other metabolic pathways.(4)HPLC-ICP-MS was used to analyze the classification of As in mycelium of HN01 under As stress and the migration rule of As compounds.The results showed that the exogenously added AsIII was enriched and stored in mycelia by STRAIN HN01,and most of the AsIII was transformed into AsV with lower toxicity,MMA with lower toxicity and basically non-toxic As B,so as to alleviate the toxic damage caused by AsIII to mycelia of B.lucidum so as to achieve the purpose of detoxification.