基于RNA-seq技术的不同发育期中华大蟾蜍耳后腺和腹皮转录组比较分析

Transcriptome Comparative Analysis of the Retroauricular Gland and Abdominal Skin of Bufo bufo gargarizans at Different Developmental Stages Based on the RNA-seq Technique

通过对中华大蟾蜍(Bufo bufo gargarizans)5个不同发育时期的耳后腺和腹皮进行转录组测序分析,挖掘参与毒素合成的关键因子,为深入研究毒素合成调控机理提供理论依据。分别取3月龄、6月龄、12月龄、24月龄、36月龄等5个发育时期的中华大蟾蜍耳后腺和腹皮进行转录组测序,利用GO和KEGG对差异表达基因功能进行分析,利用加权共表达网络分析筛选关键基因。将处于相同发育时期腹皮与耳后腺的转录组数据进行比较,分别筛选出3053、3026、1516、1028和2061个差异表达基因。由GO分类统计结果可知,差异表达基因在生物过程类别主要集中于细胞过程、单一生物体过程、代谢过程和生物调节;在分子功能类别主要富集于结合、催化活性等方面;在细胞组分类别主要聚集于细胞、细胞组分和细胞器。KEGG通路分析结果表明,差异表达基因在蟾蜍发育过程中参与多条通路,如酪氨酸代谢、过氧化物酶体和初级胆汁酸代谢等。将5个发育时期的共同差异表达基因进行比较,筛选出与类固醇代谢、初级胆汁酸代谢和过氧化物酶体相关的21个基因,利用加权共表达网络分析筛选出4个模块的6个关键基因。在不同发育时期中华大蟾蜍的腹皮与耳后腺差异表达基因中,大量代谢途径基因发生了富集,这些基因可能在调控耳后腺毒素合成中具有重要作用,为解析蟾蜍产毒分子机制奠定了基础。

To explore the key factors involved in toxin synthesis by the transcriptome sequencing analysis of the retroauricular glands and abdominal skin of Bufo bufo gargarizans at five different developmental stages,it provides a theoretical basis for further study on the regulation mechanism of toxin synthesis.Transcriptome sequencing was performed on the abdominal skin and retroauricular gland of Bufo bufo gargarizans at 5 developmental stages,including 3-month-old,6-month-old,12-month-old,24-month-old,and 36-month-old.The function of differentially expressed genes was analyzed by GO and KEGG.The key genes were screened by weighted co-expression network analysis.The transcriptome data of the abdominal skin and retroauricular gland at the same developmental stage were compared,and 3053,3026,1516,1028,and 2061 differentially expressed genes were screened,respectively.According to the GO classification statistics,the differentially expressed genes were mainly concentrated in biological processes categories such as cellular processes,monomer processes,metabolic processes,and biological regulations.In the molecular function categories,it is mainly concentrated in the binding,catalytic activity,and so on.In cellular component categories,it is mainly concentrated in the cell,component and organelle.The analysis of the KEGG pathway showed that the differentially expressed genes were involved in many pathways during toad development,such as tyrosine metabolism,peroxisome metabolism,and primary bile acid metabolism.Comparing common differentially expressed genes from 5 developmental stages,twenty-one genes related to steroid metabolism,primary bile acid metabolism,and the peroxisome were identified.Five hub genes and one key transcription factor from four modules were screened by weighted co-expression network analysis.A large number of genes of the metabolic pathway were enriched in the differentially expressed genes between the skin and retroauricular glands of Bufo bufo gargarizans at different developmental stages.These genes may play an important role in regulating the synthesis of retroauricular adenotoxins.This study lays the foundation for understanding the molecular mechanism of toad toxin production.