不同大小规格墨西哥湾扇贝(Argopecten irradians concentricus)转录组分析及生长相关基因筛选

墨西哥湾扇贝(Argopecten irradians concentricus)是中国双壳贝类养殖的重要经济品种,具有较高的研究价值,然而,转录组学及基因组学信息的匮乏,严重制约了该贝的遗传改良进程。本研究基于Illumina Hi SeqTM2000平台,对5月龄大规格(平均体质量16.05 g)和小规格(平均体质量5.57 g)墨西哥湾扇贝进行转录组测序,经de nove组装,大、小规格墨西哥湾扇贝分别获得120 563和118 794条高质量unigenes,unigene的平均长度分别为944 bp和969 bp;按照FDR≤0.001且|log2Ratio|≥1的原则,共筛选出9 901个差异表达基因,其中,大规格组相对于小规格组,上调基因4 976个(50.26%),下调基因4 925个(49.74%);六大公共数据库Blast比对结果显示,差异表达基因在Nr数据库的注释率最高,其次是GO数据库;从已获功能注释的差异表达基因中筛选得到47个生长相关候选基因,涉及多个生长因子及其受体;GO功能富集结果显示,膜、L-氨基酸运输和糖基键水解酶活性分别是细胞组分、生物过程和分子功能富集unigene最多的条目;Pathway富集分析发现,3 699条差异表达基因被成功注释到252条代谢通路中,其中33条为显著性富集通路(p<0.05),富集度最高的是焦点粘附;大规格组中共鉴定出10 870个SSRs和242 551个SNPs,小规格组中共鉴定出10 857个SSRs和228 121个SNPs。研究结果为墨西哥湾扇贝分子标记批量开发、功能相关基因挖掘以及分子遗传育种提供了理论数据支撑。     

草地贪夜蛾雄性成虫和5龄幼虫的转录组比较分析

【目的】草地贪夜蛾Spodoptera frugiperda是一种新近入侵我国的重要害虫。本研究旨在对草地贪夜蛾雄性成虫和5龄幼虫两个不同发育阶段的转录组进行比较分析。【方法】利用高通量测序技术对草地贪夜蛾雄性成虫和5龄幼虫进行转录组测序和数据组装,并对转录组数据进行功能注释和比较分析。【结果】经de novo组装共获得209 002条转录本,平均长度为687.55 bp,N50为982 bp。共有46 198条(57.43%) unigene在至少一个数据库中获得功能注释,其中1 713条(2.13%) unigene在所有数据库中均能获得注释。在GO数据库中获得205 269条unigene的注释,主要包括68个功能分类;在KEGG数据库中共有3 408条unigene得到注释,涉及277个代谢通路。共鉴定到424个嗅觉相关的基因,并且在雄性成虫和5龄幼虫之间的表达存在差异。通过比较转录组分析,在雄性成虫中鉴定到9 162个上调和6 399个下调差异表达基因(DEGs);功能富集分析发现在上调DEGs中涉及信息素以及信号转导的代谢通路显著富集,而下调DEGs中涉及解毒相关的通路显著富集。【结论】这些转录组数据为探究草地贪夜蛾的生长发育、嗅觉相关功能基因以及候选分子靶标提供资源信息。     

Comparison of Morphological and Anatomical Characteristics of <i>Taxus chinensis</i> var. <i>mairei </i>Seedlings Root under Waterlogging Stress in Different Substrates

Four different ratios of river sand, ceramic pellets, vermiculite and perlite (1:1), and field soil were selected as the substrates in this experiment, and four gradient levels of root waterlogging, half waterlogging, full waterlogging and normal were set to investigate the effects of different gradients of waterlogging stress on the root morphology of Taxus chinensis var. mairei seedlings under different substrates. In this study, the root anatomical structure of Taxus chinensis var. mairei under different waterlogging stress was observed by the paraffin section method. The roots of T. chinensis var. mairei were diarch, with no pith and resin canals. There was a large number of tannins in the pericycle of the aerial adventitious roots of seedlings adapted to waterlogging. Also, the endodermis has obvious casparian strip thickening, and there were 4-5 layers of large parenchymatous cells in the close to the inner side of the pericycle in the vascular cylinder, which could increase the storage capacity, and transport capacity of the root. Under the treatment of root waterlogging stress, the development of plant roots in the mixed substrate of vermiculite and, perlite was the earliest. Under half waterlogging stress, T. chinensis var. mairei seedlings treated with various substrates all could better adapt to the environment of waterlogging stress. Under the stress of fully waterlogging, the roots of seedlings planted in river sand substrate developed secondary growth.     

De Novo RNA Sequencing and Transcriptome Analysis of Colletotrichum gloeosporioides ES026 Reveal Genes Related to Biosynthesis of Huperzine A

Huperzine A is important in the treatment of Alzheimer’s disease. There are major challenges for the mass production of huperzine A from plants due to the limited number of huperzine-A-producing plants, as well as the low content of huperzine A in these plants. Various endophytic fungi produce huperzine A. Colletotrichum gloeosporioides ES026 was previously isolated from a huperzine-A-producing plant Huperzia serrata, and this fungus also produces huperzine A. In this study, de novo RNA sequencing of C. gloeosporioides ES026 was carried out with an Illumina HiSeq2000. A total of 4,324,299,051 bp from 50,442,617 high-quality sequence reads of ES026 were obtained. These raw data were assembled into 24,998 unigenes, 40,536,684 residues and 19,790 genes. The majority of the unique sequences were assigned to corresponding putative functions based on BLAST searches of public databases. The molecular functions, biological processes and biochemical pathways of these unique sequences were determined using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) assignments. A gene encoding copper amine oxidase (CAO) (unigene 9322) was annotated for the conversion of cadaverine to 5-aminopentanal in the biosynthesis of huperzine A. This gene was also detected in the root, stem and leaf of H. serrata. Furthermore, a close relationship was observed between expression of the CAO gene (unigene 9322) and quantity of crude huperzine A extracted from ES026. Therefore, CAO might be involved in the biosynthesis of huperzine A and it most likely plays a key role in regulating the content of huperzine A in ES026.