吉林省10个柞蚕品种的线粒体基因组分析

Analysis of Complete Mitochondrial Genomes of 10 Strains of Antheraea pernyi from Jilin Province

吉林省是我国二化性柞蚕(Antheraea pernyi)的种源基地,种茧产量占全国用种量的80%以上。本文测定了吉林省10个柞蚕品种的线粒体基因组,并结合已有的8个柞蚕品种的线粒体基因组重建了这些品种的系统发育关系。吉林省10个柞蚕品种中,选大4号的线粒体基因组为15 570 bp,其余9个品种(吉青、高油1号、永青、超杂1号、吉抗109、吉黄2号、选大2号、吉柞889、吉柞882)的线粒体基因组长度均为15 572 bp;这10个柞蚕品种的线粒体基因组均编码13个蛋白编码基因、22个tRNA基因和2个rRNA基因。系统发育分析发现,供试的18个柞蚕品种分为3个线粒体DNA世系群,即豫早1号世系群、青黄1号世系群、青6号世系群;吉林的柞蚕品种5个属于青黄1号群,5个属于青6号群。18个柞蚕品种的线粒体基因组共鉴定出17个单倍型,其中吉黄2号和选大2号的序列完全一致。序列分析共鉴定出224个单核苷酸变异位点(包括20个插入/缺失位点),豫早1号群5个品种的多态性位点高达164个;青黄1号群6个品种的多态性位点仅为11个;青6号群7个品种的多态性位点为16个。分子变异方差分析(AMOVA)表明,豫早1号群与青6号群和青黄1号群之间的分化系数Fst高达0.66,而青6号群和青黄1号群之间的分化系数Fst也达到0.26。研究结果从分子水平揭示了这10个吉林柞蚕品种与辽宁种群高度同源;与河南品种资源相比,供试的10个吉林柞蚕品种资源的遗传基础较为狭窄。本研究为深入理解吉林柞蚕品种资源的遗传基础与创新利用提供了基本信息。

Jilin Province is the seed cocoon base of bivoltine Chinese oak silkworm(Antheraea pernyi) in China, providing over 80% seed cocoons of the total production. In this study, complete mitochondrial genomes of 10 A. pernyi strains from Jilin Province were determined, and the phylogenetic relationship between these strains was reconstructed together with eight known A. pernyi mitochondrial genomes. The length of the mitochondrial genome of Xuanda 4 was 15 570 bp, whereas those of the other 9 varieties(Jiqing, Gaoyou 1, Yongqing, Chaoza 1, Jikang 109, Jihuang 2, Xuanda 2, Jizuo 889 and Jizuo 882) were all 15 572 bp. All the ten mitochondrial genomes determined in this study encoded 13 protein-coding genes, 22 transfer RNAs and 2 ribosomal RNAs. Phylogenetic analysis revealed the presence of three mitochondrial DNA lineages in the 18 varieties, designated here as Yuzao 1 lineage, Qinghuang 1 lineage and Qing 6 lineage respectively. Half of these ten varieties from Jilin Province were grouped into Qinghuang 1 lineage and Qing 6 lineage respectively. Seventeen halotypes were identified among 18 A. pernyi mitochondrial genomes available to date. The mitochondrial genome of Jihuang 2 was identical to that of Xuanda 2. By sequence comparison, a total of 224 single nucleotide variations(SNVs) including 20 indels were identified. About 164 SNVs were found in 5 varieties of Yuzao 1 lineage, whereas only 11 SNVs in 6 varieties of Qinghuang 1 lineage and 16 SNVs in 7 varieties of Qing 6 lineage were identified. AMOVA analysis indicated a high genetic differentiation coefficient(Fst>0.66) between Yuzao 1 and Qing 6 lineages, and between Yuzao 1 and Qinghuang 1 lineages, but a remarkable Fst(=0.26) between Qing 6 and Qinghuang 1 lineages. The results revealed that these 10 varieties of Jilin Province were closely related to the Liaoning population at molecular level, and that the genetic basis of the 10 A. pernyi germplasm resources of Jilin Province was relatively narrow compared to those of Henan Province. This study provides some basic information on the genetic base and innovation utilization of A. pernyi strain resources in Jilin Province.