结球甘蓝游离小孢子热激处理下差异表达基因分析  

Exploring differentially expressed genes of isolated microspore under heat shock in cabbage

作　　者：曾爱松[1] 李家仪 李英[3] 宋立晓[1] 侯喜林[3] 严继勇[1] ZENG Aisong;LI Jiayi;LI Ying;SONG Lixiao;HOU Xilin;YAN Jiyong(Institute of Vegetable Crops,Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement,Nanjing 210014,China;College of Biological Sciences,China Agricultural University,Beijing 100094,China;State Key Laboratory of Crop Genetics and Germplasm Enhancement,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]江苏省农业科学院蔬菜研究所/江苏省高效园艺作物遗传改良重点实验室,江苏南京210014 [2]中国农业大学生物学院,北京100094 [3]南京农业大学作物遗传与种质创新国家重点实验室,江苏南京210095

出　　处：《南京农业大学学报》2019年第2期236-245,共10页Journal of Nanjing Agricultural University

基　　金：国家重点研发计划项目(2017YFD0101804)

摘　　要：[目的]本文旨在探讨结球甘蓝游离小孢子培养早期体胚发生的分子机制,分析游离小孢子在热激处理下的基因表达谱。[方法]将易出胚结球甘蓝高代自交系611单核靠边期小孢子分别在体外32.5℃培养1 d(热激处理,E2)、体内正常生长1 d(对照组1,E3)及体外25℃培养1 d(对照组2,E5),利用转录组测序技术(RNA-Seq)对3个处理的小孢子文库进行差异基因表达谱分析,并鉴定热激处理下早期体胚发生的响应基因。[结果]将3个处理的小孢子Uni Gene表达量依次进行两两相比,即E2 vs E3、E2 vs E5以及E3 vs E5,分别鉴定出2 506、1 073和3 322个差异表达基因。基因本体(gene ontology,GO)聚类分析表明,热激处理下的差异表达基因显著富集到细胞组分中的细胞部件、细胞及细胞器;在分子功能中,这些基因在结合、催化活性及核酸结合转录因子活性中的比例最高;在生物过程中的细胞过程、代谢过程及刺激反应等类别中的比例也最高。京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)通路分析显示,热激处理下的差异表达基因显著富集到植物激素信号转导、植物病原互作、淀粉和糖代谢、抗坏血酸代谢、苯丙氨酸代谢以及多糖降解等途径。进一步对抗坏血酸代谢途径相关基因进行分析,抗坏血酸过氧化物酶基因APX1和APX2,半乳糖脱氢酶基因Gal DH以及乙醛脱氢酶基因AD在体外32.5℃培养1 d后均显著上调表达。[结论]通过转录组学方法揭示了结球甘蓝游离小孢子在热激处理下基因组的表达变化,鉴定了可能与早期体胚发生相关的抗坏血酸代谢途径基因,为进一步研究甘蓝小孢子体胚发生的分子机制奠定了基础。[Objectives] In order to investigate the molecular mechanism of early somatic embryogenesis in isolated microspore culture(IMC)of cabbage,the gene expression profile of isolated microspores under heat shock was analyzed.[Methods] The microspore at late uninucleate stage of a high-responsive inbred line of cabbage 611 was cultured for 1 day at 32.5 ℃(heat shock treatment,E2),1 day in vivo(control 1,E3),and 1 day at 25 ℃(control 2,E5).The differentially expressed genes(DEG)profiles of three microspore libraries were analyzed by transcriptome sequencing(RNA-Seq),and the response genes of early somatic embryogenesis under heat shock treatment were identified.[Results] The comparisons of UniGene expression of the isolated microspore among E2 vs E3,E2 vs E5,and E3 vs E5 indicated that 2506,1073 and 3322 DEG were identified.Gene ontology(GO)clustering analysis revealed that DEG under heat shock treatment was significantly enriched in cell part,cell and organelle in cell component,binding,catalytic activity and nucleic acid binding transcription factor activity in molecular function,cellular process,metabolic process and response to stimulus in biological processe,etc..Kyoto encyclopedia of genes and genomes(KEGG)pathway analysis indicated that DEG was significantly involved in the multiple processes of plant hormone signal transduction,plant-pathogen interaction,starch and sucrose metabolism,ascorbate and aldarate metabolism,phenylpropanoid biosynthesis,and other glycan degradation,etc..Furthermore,L-ascorbate peroxidase 1 gene(APX 1),L-ascorbate peroxidase 2 gene(APX 2),L-galactose dehydrogenase gene(GalDH)and aldehyde dehydrogenase(AD)gene which were related to ascorbate and aldarate metabolism were up-regulated significantly culturing 1 day at 32.5 ℃.The results showed that these genes might play an important role during embryogenesis in IMC.[Conclusions] The study revealed the changes of genome expression of isolated microspore of cabbage under heat shock treatment by transcriptome,and identified the ascorbic

关 键 词：结球甘蓝 热激处理 体胚发生 基因表达谱测序 小孢子培养 

分 类 号：S635.3[农业科学—蔬菜学]