Pax2基因异常参与孤独症谱系障碍发病的生物信息学分析

Bioinformatics analysis of Pax2 gene abnormalities involved in pathogenesis of autism spectrum disorders

目的对配对盒2(Pax2)相关孤独症谱系障碍(ASD)易感基因进行生物信息学分析,探讨Pax2基因参与ASD发病的可能机制。方法(1)将Pathway Commons数据库中与Pax2基因相关的基因(606个)和Simons基金会孤独症研究计划(SFARI)数据库中ASD易感基因(1023个)取交集得到65个Pax2基因相关ASD易感基因。在基因功能分析网站Metascape对Pax2基因相关ASD易感基因进行基因本体论(GO)和京都基因与基因组数据库(KEGG)通路富集分析。使用Cytoscape软件cytoHubba插件的最大团中心度(MCC)算法,筛选前10个核心Pax2基因相关ASD易感基因。(2)取3只13周龄雄性Pax2-nestin小鼠(实验组)及3只同龄雄性C57 BL/6J小鼠(对照组),采用Western blotting实验检测2组小鼠海马组织中谷氨酸受体2B亚基(GluN2B)蛋白的表达。结果(1)GO分析显示Pax2基因相关ASD易感基因在生物学过程(BP)本体主要富集于跨突触信号、行为、脑发育、化学突触传递的调节、胶质细胞再生、小脑形态发育、谷氨酸能突触传递、记忆等子集,在细胞组分(CC)本体主要富集于突触后、树突、β连环蛋白-T细胞因子(TCF)复合物、树突分支等子集,在分子功能(MF)本体主要富集于突触后密度蛋白95/果蝇圆盘大肿瘤抑制蛋白/紧密连接带-1蛋白(PDZ)结合结构域、转录因子结合、跨膜受体蛋白酪氨酸激酶活性、谷氨酸受体活性、微管蛋白结合等子集。KEGG通路富集分析显示Pax2基因相关ASD易感基因主要分布在丝裂原活化蛋白激酶(MAPK)信号通路、长时程抑制、谷氨酸能突触等通路。核心Pax2基因相关ASD易感基因为Gria1、Dlg2、Ntrk2、Grid2、Igf1、Jmjd1c、Ldb1、Tcf4、Tcf7l2、Adrb2。(2)Western blotting实验显示,对照组、实验组小鼠海马组织中GluN2B蛋白的相对表达量分别为2.36±0.60、0.85±0.44,差异有统计学意义(P<0.05)。结论Pax2基因异常可能导致Pax2基因相关ASD易感基因的表达或功能异常,并通过多种机制参与ASD的发病。

Objective To explore the mechanism of paired box 2(Pax2)gene involved in autism spectrum disorder(ASD)pathogenesis by performing a bioinformatics analysis on Pax2-associated ASD susceptibility genes.Methods(1)Pax2-associated genes(n=606)identified from Pathway Commons database and ASD susceptibility genes(n=1023)identified from Simons Foundation Autism Research Initiative(SFARI)database were intersected and yielded Pax2-associated ASD susceptibility genes(n=65).Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses of Pax2-associated ASD susceptibility genes were performed at Metascape,a gene function analysis website.The top 10 core Pax2-associated ASD susceptibility genes were screened by maximal clique centrality(MCC)algorithm of Cytoscape cytoHubba plugin.(2)Glutamate receptor subunit 2B(GluN2B)expressions in hippocampal tissues of 313-week-old male Pax2-nestin mice(experimental group)and 313-week-old male C57 BL/6J mice(control group)were detected by Western blotting.Results(1)GO-biological process(BP)showed that Pax2-associated ASD susceptibility genes were enriched in trans-synaptic signaling,behavior,brain development,modulation of chemical synaptic transmission,gliogenesis,cerebellum morphogenesis,synaptic transmission(glutamatergic),and memory categories;GO-cellular component(CC)showed that Pax2-associated ASD susceptibility genes were enriched in the post-cynapse,dendrite,β-catenin protein-T cell factor(TCF)complexes,and dendritic shaft categories;GO-molecular function(MF)showed that Pax2-associated ASD susceptibility genes were mainly enriched in PDZ domain binding,transcription factor binding,transmembrane receptor protein tyrosine kinase activity,glutamate receptor activity,and tubulin protein binding categories.KEGG showed that Pax2-associated ASD susceptibility genes were mainly involved in MAPK signaling pathway,long-term depression,and glutamatergic synapse categories.The core Pax2-associated ASD susceptibility genes included Gria1,Dlg2,Ntrk2,Grid2,Igf1,Jmjd1c,Ldb1,Tcf4,Tcf7l2 and Adrb2.(2)Western blotting showed that the relative GluN2B protein expression in hippocampal tissues of mice in the control group and experimental group were(2.36±0.60)and(0.85±0.44),respectively,with statistical significance(P<0.05).Conclusion Pax2 gene abnormality may lead to abnormal expression or function of Pax2-associated ASD susceptibility genes and participate in ASD pathogenesis through a variety of mechanisms.