| Sugarcane is one of the world’s most important crop for sugar and biomass production.It also provides important raw material for the production of bio-ethanol and high value added products.In addition to sugar,sugarcane extract also contains a large amount of flavonoids,such as anthocyanins;this is a natural water-soluble pigment with economic value and health care function.In recent years,the research on the molecular mechanism of anabolism of sugarcane anthocyanins has gradually become a hot spot,in order to explore the key genes in the anabolic process of sugarcane anthocyanin,through the use of green sugarcane(FuNong 15)and black sugarcane(Badila),Transcriptome sequencing and data analysis of the sugarcane pectin and cane skin(Badila)sites,and the discovery of relevant color functional genes between different sugarcane varieties,in order to explore the molecular mechanisms of anabolic metabolism of sugarcane stem anthocyanins and subsequent gene cloning.Molecular marker screening and genetic improvement and breeding provide basis for determining the anthocyanin content in different parts of sugarcane and its gene regulation.The results of the study are as follows:(1)In the most mature period of anthocyanin expression,samples were taken of the green cane(FuNong 15)and the black sugarcane(Badila)preserved in the Sugarcane Germplasm Resource Center of the National Sugarcane Engineering Center of Fujian Agriculture and Forestry University.The distribution of anthocyanins in the two parts of the cane skin parts of FuNong 15 and Badila,the cane skin of Badila and the cane pulp of Badila was not uniform.Among them,the total anthocyanin content in the cane skin area of Badila is abundant.(2)UPLC-Q-TOF/MS technology was used to qualitatively and quantitatively analyze the anthocyanin content in the cane skin and cane pulp of FuNong 15 and Badila.The results showed that four anthocyanins were detected in the cane skin of FuNong 15 and Badila.The four anthocyanin components found were;cyanidint,peonidint,pelargonidin and malvidin.The two anthocyanins are the most abundant in the peony pigments,while the cyanidin and peonidint are usually purple in the higher plants.In addition,only the malvidin was detected in the cane pulp and its mass concentration was much lower than that of its own cane skin.(3)Denovo splicing results of transcriptome sequencing,total 73,916 Unigenes were assembled and compared with the five public databases(NR,SWISS-PROT,COG,KEGG and GO).The results that the number of Unigenes successfully annotated from at least one of the above five databases were 43,827,accounting for approximately 59.29%.Through the transcriptome sequencing analysis and gene annotation of sugarcane and cane skin of different colored sugarcane varieties in mature period,a total of 39 differentially expressed Unigenes may be involved in the anthocyanin synthesis pathway,including 15 structural genes[PAL(2),CHS(3),F3H(3),DFR(4),ANS(2),UFGT(1)]and 24 regulatory genes[MYB(10),bHLH(6),WD40(8)].(4)According to the gene annotation information,six anthocyanin key enzyme synthesis genes(PAL、DFR、F3H、CHS、UFGT and ANS)were verified through quantitative PCR.The results showed that the four key enzyme genes in the cane skin were increased to different degrees in the black sugarcane(Badila)compared with the green skin sugarcane FuNong15.Compared with the black sugarcane(Badila)own cane pulp and cane skin,the six key enzyme gene expression in the cane pulp is very low,and the difference is very significant with the cane skin;This is consistent with transcriptome sequencing.It is speculated that these key enzyme genes may play a major role in determining the anthocyanin biosynthesis and accumulation in the cane skin. |
