在患CyHV-2病的异育银鲫肠道黏膜中胆固醇、胆汁酸代谢通路基因的差异表达

GENE DIFFERENCE EXPRESSION OF CHOLESTEROL AND BILE ACID METABOLISM PATHWAY IN INTESTINAL MUCOSA WITH THE CYHV-2 DISEASE CARASSIUS AURATUS GIBELIO

为了探讨CyHV-2疾病条件下异育银鲫胆汁酸肠肝循环代谢途径主要基因表达活性的变化,以患CyHV-2病的、正常的异育银鲫肠道黏膜为材料,提取总RNA,采用RNA-Seq测序、对单一基因进行注释,并进行KEGG富集分析、单一基因差异表达分析。结果显示,肠道黏膜组织有7770个基因显著性差异表达,其中,差异表达上调基因数为3335个、差异表达下调的基因数为4435个,表明CyHV-2病的发生对肠道黏膜组织基因表达产生了重大的影响。病鱼胆固醇、胆汁酸生物合成代谢途径的酶、蛋白质的基因显著性差异表达,显示肠道黏膜胆固醇、胆汁酸合成代谢受到显著性影响。参与胆固醇、胆汁酸合成代谢调节作用,以及胆固醇、胆汁酸分泌、吸收、转运等生理过程的蛋白质、酶的基因也是差异表达下调,胆汁酸肠肝循环有出现代谢障碍的趋势。结果表明,CyHV-2病的发生对肠道黏膜组织基因表达产生了严重影响,对胆固醇、胆汁酸的合成代谢途径、胆汁酸肠肝循环途径的基因表达产生了严重影响,将导致病鱼体内胆固醇、胆汁酸量的不足。患CyHV-2病病鱼血清胆汁酸含量下降了99%、胆固醇含量下降了10%,证实了上述基因差异表达的趋势。

Gibel carp(Carassius auratus gibelio)infected with Cyprinid herpesvirus2(CyHV-2),damaged many organsincluding intestinal mucosa.Total RNA of intestinal mucosa from CyHV-2diseased and normal gibel carp wereextracted for RNA-Seq.Transcriptome assembly from RNA-Seq data without a reference genome was conducted byTrinity(version:v2012-10-05,min_kmer_cov2)software.Single gene is annotated by using different databases.Softwareand the database of the functional gene annotation are SwissProt(NCBI blast2.2.27+,Blast2GO v2.5),KOG(NCBI blast2.2.27+),PFAM(HMMER3.0package),KEGG(KOBAS,NCBI blast2.2.27+).Gene expression wasanalyzed by edgeR package.3335up-regulated genes and4435down-regulated genes were observed,indicating a significantinjury in the intestinal mucosa by CyHV-2infection.The metabolic disorder for enterohepatic circulation ofbile acids was supported by the reduced gene expression that regulate cholesterol and bile acid synthesis metabolismand other physiological processes,secretion,absorption and transportation.As a consequence,CyHV-2infection inCrucian carp decreased the serum bile acid content by99%and cholesterol content by10%.