木贼镰孢菌D25-1全基因组序列的测定及结构分析

Determination and structural analysis of whole genome sequence of Fusarium equiseti D25-1

木贼镰孢菌是多种植物的病原菌,也具有益生作用,功能复杂多样。本研究基于Illumina Hiseq 4000和Pac Bio平台对木贼镰孢菌D25-1全基因组序列进行了测定及组装,共组装出16个基因组片段,GC含量48.01%,总长40 776 005个碱基,Gap数为0。对内含子、外显子、基因长度、非编码RNA、重复序列等基因组信息均进行分类统计,外显子40 110个,总长19787 286 bp,内含子26 281个,总长2 290 434 bp,多数基因长度为500~1 499 bp,tRNA 333个,rRNA 71个,sRNA 69个,snRNA 31个,miRNA 108个,共预测的重复序列1 713 918 bp,占基因组4.2033%。比较基因组学分析发现木贼镰孢菌组装结果较好,特有基因3 483个和共有基因1 805个,并对共有基因进行了COG分类注释。基因家族分析发现2 500多个单拷贝同源基因。构建进化树发现木贼镰孢菌和假禾谷镰孢菌的遗传距离最近,在全基因组水平上确定了其进化地位。本研究为基因表达的调控机制、基因功能演化分析、病害防控等研究提供基础的数据。

Although as a pathogen of a variety of plants,Fusarium equiseti also plays a probiotic role and functions complexly and diversely.Based on Illumina Hiseq 4000 and Pac Bio platform,the whole genome sequence of F.equiseti D25-1 was determined and assembled in this study.A total of 16 genome fragments were assembled,with GC content of 48.01%,Gap number of zero,and 40 776 005 bp in length.A classification and statistics were performed on intron,exon,gene length,non-coding RNA and repetitive sequence.There were 40 110 introns and 26 281 exons with total length of 19 787 286 bp and 2 290 434 bp,respectively.The assembled genome contains estimated genes averaging from 500 to 1 499 bp in length,with 333 copies for tRNA,71 copies for rRNA,69 copies for sRNA,31 copies for snRNA and 108 copies for miRNA,and repetitive sequences were1 713 918 bp in total,comprising 4.2033%of the whole genome.Comparative genomics analysis demonstrated that F.equiseti has 3 483 unique genes and 1 805 core genes.COG classification annotation of core genes was carried out.Gene family analysis revealed that there were more than 2 500 single copy orthologs.It was found that the genetic distance between F.equiseti and F.pseudograminearum was the closest by constructing evolutionary tree,and the evolutionary position was determined at the whole genome level.The comprehensive analysis on whole genome sequence of F.equiseti would enhance our understanding of regulation of gene expression,evolution of gene function,disease prevention and control on a genomic scale.