Integrated analysis of genome-wide profiling of lncRNA and mRNA expression and functional networks after botulinum toxin type A injection into submandibular gland of rats.

Abstract: Backgroud: This study was to explore long noncoding RNA (lncRNA) and messenger RNA (mRNA) expression profiles and construct functional networks to analyze their biological functions when botulinum toxin type A (BTXA) inhibited salivary secretion. Methods: BTXA and saline were injected into the submandibular gland of rats as the BTXA group and control group, respectively. Morphological and secretory function tests validated the animal models. Microarray analysis was applied to identify the expression variation of lncRNA and mRNA and were confirmed by qRT-PCR. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to explicit the biological functions. The construction of functional networks including lncRNA-mRNA co-expression network and competing endogenous RNA (ceRNA) network was to reveal the interaction between coding and noncoding genes. Results: A total of 254 lncRNAs and 631 mRNAs were differentially expressed (DE) between the control group and the BTXA group. Ten lncRNAs and eleven mRNAs were confirmed by qRT-PCR and the results were consistent with the microarray analysis. The bioinformatic analysis found that most of mRNAs were closely related to transmembrane transporter activity. LncRNA-mRNA co-expression network and ceRNA network were constructed and identified several critical mRNA-lncRNA axes and key microRNAs related to salivary secretion, respectively. Conclusions: Our study identified DE lncRNAs and mRNAs through microarray analysis and explored the biological functions and interaction between coding and noncoding genes through bioinformatics analysis. These findings may provide new directions for the mechanism of BTXA to inhibit salivary secretion.摘要： 背景：本研究旨在探讨A型肉毒杆菌毒素（botulinum toxin type A, BTXA）抑制唾液分泌过程中，长链非编码RNA（long noncoding RNA, lncRNA）与信使RNA（messenger RNA, mRNA）的表达谱，并构建功能网络以分析二者的生物学功能。 方法：将BTXA与生理盐水分别注射至大鼠下颌下腺，构建BTXA组与对照组。通过形态学与分泌功能实验验证动物模型构建成功。采用微阵列分析鉴定lncRNA与mRNA的表达差异，并通过实时荧光定量聚合酶链反应（quantitative real-time polymerase chain reaction, qRT-PCR）验证芯片结果。开展基因本体论（Gene Ontology, GO）与京都基因与基因组百科全书（Kyoto Encyclopedia of Genes and Genomes, KEGG）通路分析，以明确相关生物学功能。构建lncRNA-mRNA共表达网络与内源竞争RNA（competing endogenous RNA, ceRNA）网络两类功能网络，以揭示编码基因与非编码基因间的相互作用机制。 结果：对照组与BTXA组间共鉴定出254个差异表达lncRNA与631个差异表达mRNA。经qRT-PCR验证，10个lncRNA与11个mRNA的表达变化趋势与微阵列分析结果一致。生物信息学分析显示，多数差异mRNA与跨膜转运体活性密切相关。成功构建lncRNA-mRNA共表达网络与ceRNA网络，分别筛选出若干与唾液分泌相关的关键mRNA-lncRNA调控轴以及核心微小RNA（microRNA）。 结论：本研究通过微阵列分析鉴定出差异表达的lncRNA与mRNA，并通过生物信息学分析探讨了编码基因与非编码基因的生物学功能及相互作用关系。本研究结果可为BTXA抑制唾液分泌的作用机制研究提供新的思路与方向。