Abstract: In order to investigate the molecular biological mechanisms of broccoli microspore embryogenesis, the Illumina HiSeq^TM 2000 platform was utilized to analyze and annotate transcriptomes of the microspores, cultured at 32.5℃for 17 h and 24 h and at 25℃ for 0, 1, 6 d in this research. The results showed that a total of 174324 Unigenes were produced, among which 144 194 were annotated in GO、COG、KEGG、NR、Swissprot and Pfam database. The analysis of gene ontology function enrichment revealed that some important biological processes related to microspore embryogenesis, such as cell part, cell and organelle, binding and catalytic activity, metabolic process, cellular process and single-organism process, etc, got significantly enriched. The frequencies of R、L、K、T and O were much higher than others in COG function classification. The results of KEGG pathways enrichment showed that differentially expressed genes produced from microspores after heat shock tended to cluster into the pathway of protein processing in endoplasmic reticulum, the pathways of plant-pathogen interaction, plant hormone signal transduction and spiceosome, etc. The results laid a good foundation for further study on the physiological and biochemical and molecular mechanisms of broccoli microspore embryogenesis.

Key words: microspore embryogenesis, differential expressed gene, transcriptome, gene function annotation

摘要： 为探明青花菜小孢子胚胎发育的分子生物学机制,本研究利用Illumina HiSeqTM 2000平台对在32.5℃环境下分别培养17 h和24 h以及25℃环境下分别培养0、1 和6 d的小孢子进行转录组分析及基因功能注释。结果表明,共获得174 324条Unigenes,其中有144 194条注释到GO、COG、KEGG、NR、Swissprot和Pfam数据库。GO注释显示,小孢子差异表达基因在细胞部分、细胞和细胞器、结合和催化活性、代谢过程、细胞过程和单一生物过程功能亚类中所占比较最高;功能分类中一般功能预测(R)、复制、重组与修复(L)、转录(K)、信号转导机制(T)和翻译后修饰、蛋白质周转、分子伴侣(O)在COG同源分类所占比例最高;KEGG注释结果表明,热击后小孢子差异基因最显著富集通路为内质网蛋白加工代谢途径、植物病原互作及植物激素信号转导剪接体途径。本试验结果为进一步深入研究青花菜小孢子胚胎发生的生理生化和分子机制奠定了理论基础。

关键词: 小孢子胚胎发育, 差异表达基因, 转录组, 基因功能注释