意大利蜜蜂工蜂中肠响应东方蜜蜂微孢子虫胁迫的可变剪接基因分析

Analysis on the response of alternatively splicing genes in Apis mellifera ligustica workers′ midguts to Nosema ceranae stress

基于前期已获得的意大利蜜蜂(Apis mellifera ligustica)工蜂中肠转录组数据,在全转录组水平上对意大利蜜蜂的可变剪接基因(alternatively spliced gene,ASG)进行鉴定和分析,旨在揭示ASG在宿主响应东方蜜蜂微孢子虫(Nosema ceranae)胁迫中的作用.在正常意大利蜜蜂7和10日龄工蜂中肠(Am7CK、Am10CK)和东方蜜蜂微孢子虫胁迫的意大利蜜蜂7和10日龄工蜂中肠(Am7T、Am10T)样品中检测到可变剪接事件数分别为73383、85618、79813和74693次,对应的基因数分别为9586、10063、9829和9622个,平均每个ASG上发生的可变剪接事件数分别为7.66、8.50、8.12和7.76次.各样品的可变剪接事件中外显子跨越的数量最多,分别为4411、5247、4993和4629个.Venn分析结果显示,Am7CK、Am10CK、Am7T和Am10T中的共有ASG数为9056个,特有ASG数分别为100、153、275和95个.GO分类结果显示,这些共有ASG分布在50个功能条目,特有ASG分别分布于26、30、33和24个功能条目.KEGG代谢通路富集分析结果显示,上述共有ASG富集在325个代谢通路,包括内质网蛋白加工、核糖体和RNA转运等;特有ASG分别富集在31、104、126和22个代谢通路.研究结果提供了意大利蜜蜂响应东方蜜蜂微孢子虫胁迫过程中的ASG数量和种类信息,揭示宿主ASG在胁迫响应中参与了新陈代谢和细胞免疫,为关键ASG的筛选和功能研究建立了数据基础.

To illuminate the role of alternative splicing genes(ASGs) in host′s response to Nosema ceranae stress, the ASGs of Apis mellifera ligustica worker were identified and analyzed based on the transcriptome data of its midgets. A total of 73 383 and 85 618 alternative splicing events occurred in 9 586 and 10 063 genes identified from the midguts of normal 7-and 10-day-old A.m.ligustica workers(shorted for Am7 CK and Am10 CK), while 79 813 and 74 693 alternative splicing events occurred in 9 829 and 9 622 genes in the midgets of N.ceranae-stressed workers(Am7 T and Am10 T). The averages of alternative splicing events for Am7 CK, Am10 CK, Am7 T and Am10 T were 7.66, 8.50, 8.12 and 7.76, respectively. Of these alternative splicing events, exon span was the most abundant one in every groups, with the numbers were 4 411, 5 247, 4 993 and 4 629, respectively. Venn analysis showed the number of ASGs in common reached 9 056, and the numbers of specific ASGs for Am7 CK, Am10 CK, Am7 T and Am10 T were 100, 153, 275 and 95, respectively. GO classification indicated these shared ASGs were classified in 50 functional terms, while the specific ASGs were engaged in 26, 30, 33 and 24 terms, respectively. Moreover, KEGG pathway analysis demonstrated the shared ASGs were enriched in 325 pathways which included protein processing in endoplasmic reticulum, and ribosome and RNA transport;while the specific ASGs involved 31, 104, 126 and 22 pathways, respectively. Our results reveal the participation of host ASGs in the metabolism and immune defense induced by N.ceranae, and provides the theoretical basis for the further screening and investigation of key ASGs.