Molecular Mechanism Of Sugar Metabolism Related Genes In Goji Berry ?Lycium Barbarum L.? Fruit Under Different CO₂ Concentration

Goji berry?Lycium barbarum L.?,is one of the important economic crops in China,due to its exceptional nutrient value and medicinal benefits that including some active component,such as Lycium barbanan polysaccharide,flavonoids,and caroteniods.At presnet,cliamate change has become an important factoer impact crops development and food security,studied has found that under elevated CO₂ treatment the taotal sugar,caroteroid levels has reduced in goji berry fruits.Althought long-term CO₂ has influence the sugar metabolism and quality of goji berry,the underlying molecular mechanisms remain unknow.Therefore,in order to further explore the mechanism of sugar metabolism regulation in goji berry fruit under elevated CO₂ treatment,transcriptome was used to study the transcript characteristics of goji berry fruit,and further screening differential expression genes regulated sugar metabolism,and cloning and expression analysis of the three key genes in involed in sugar metabolism.Summarized as follows:1.The transcriptome analysis the goji berry fruit under elevated(720?mol-mol^-1)and Ambient(400?mol-mol^-1)CO₂ treatment for 120 days.Total obtained 44.45Gb Clean Data,and assembled 26,498,396 contig,196,844 transcripts and 81,100 unigenes with an average length of 42.76 bp,1232.76bp and 894.60 bp,and N50 lengths are 45 bp,1840 bp and 1266 bp,respectively.Through nucleic acid and protein function annotations,34,858?43%?Unigene annotations to the NR protein database;21,908?27%?Unigene annotations to the Swiss-Port database;21,489?26.5%?Unigene annotations to the Pfam database;18727?23.1?%)Unigene notes to the KOG database;there are 16710?20.6%?Unigene annotations into the 55 functional groups of the GO database;and 7090?8.7%?Unigene annotations into the KEGG database.2.73 differentially expressed differential genes were screened by differentially expressed gene analysis,55 of which were up-regulated and 18 were down-regulated;further differentially expressed genes were analyzed for significant enrichment of GO and KEGG,found that 34 differentially expressed genes were enriched into GO database,and 8 genes were involved in 12 Pathways of KEGG.By compared analyzed between elevated and ambient CO2 treatment genes involved in sugar metabolism,there were three genes4-epimerase),LBGALA?alpha-galactosidase?and LBMS?synthase?were significantly up-regulated in four sugar metabolic pathways.3.The RACE was used to clone the LBGAE,LBGALA and LBMS gene c DAN sequences,which were 1837 bp,1233 bp and 2449 bp,encoding 411,410 and 571 amino acids,respectively.The gene LBGALA contains a signal peptide cleavage site.Multiple sequence alignments and phylogenetic tree construction analysis indicated that the three genes have higher homology with Capsicum annuum,Solanum tuberosum,Solanum lycopersicum and Nicotiana tabacum.qRT-PCR quantitative analysis showed that all three genes were significantly expressed in the fruits treated 120 days with elevated CO₂.By analyzing the metabolic pathways involved in the three genes,these genes were mainly involved in galactose,sucrose,glucose,fructose and intermediate acetone.It is preliminarily indicated that the genes LBGAE,LBGALA and LBMS are key genes regulating glucose metabolism in response to elevated CO₂ concentrations.