基于2b-RAD技术的家蚕BmNPV抗性关联基因的全基因组筛查  

Genome-wide Screening of Silkworm Genes Related to Bm NPV Resistance Based on 2b-RAD Technology

作　　者：张正斌 张业顺[1,2] 方瑷 何小柏[1,2] 徐安英[1,2] 吴阳春[1,2] 张国政 

机构地区：[1]江苏科技大学生物技术学院,江苏镇江212018 [2]中国农业科学院蚕业研究所,农业部蚕桑遗传改良重点实验室,江苏镇江212018

出　　处：《蚕业科学》2017年第6期905-912,共8页ACTA SERICOLOGICA SINICA

基　　金：现代农业产业技术体系建设专项(No.CARS-18)

摘　　要：不同家蚕品种对家蚕核型多角体病毒(Bm NPV)的抵抗性存在较大差异,家蚕抗性品系AN、野BN对Bm NPV侵染具有较强的抵抗性。用易感家蚕品系C108分别与AN和野BN杂交、回交,构建两个抗性品系的BC3M和BC4M分离群体,利用简化基因组测序技术2b-RAD(基于IIB型限制性内切酶的RAD)进行亲本和杂交分离群体的基因组测序,通过生物信息学方法筛选位于染色体上与抗性相关的多态性SNP标记,进行抗性品种的基因型分析。对3个亲本及2个抗性分离群体样本基因组DNA构建的2b-RAD标签文库进行Illumina测序,获得抗性亲本AN、野BN的多态性SNP标记11 919个和12 293个。对抗性分离群体全基因组染色体的Bm NPV抗性关联SNP标记指数(SNP-index)进行分析,结果表明亲本品系AN、野BN的Bm NPV抗性相关SNP标记分布在多个染色体上,其中AN的全基因组中抗性贡献率前5位是第5、10、27、23和4号染色体,野BN的全基因组中抗性贡献率前5位的是第4、27、15、18和6号染色体,有多个SNP-index高值位点与已知Bm NPV抗性相关基因的位置具有较高的一致性。推测AN、野BN两个品系的Bm NPV高抗性与抗性主基因和其他抗性基因的联合作用有关。The resistance of different silkworm（ Bombyx mori） varieties to Bombyx mori nucleopolyhedrovirus（ Bm NPV）is quite different. Silkworm strains AN and Ye-BN have high resistance against Bm NPV. A susceptible silkworm strain named C108 was used to hybridize and back-cross with AN and Ye-BN respectively for construction of two segregation populations（ named BC3 M and BC4 M） of the two resistant strains. Simplified genome sequencing technology 2 b-RAD（ RAD based on type IIB restriction endonuclease） was employed to sequence genomes of the above parental strains and hybrid segregation populations. Bioinformatic methods were employed to screen resistance-related polymorphic SNP markers on chromosomes for analyzing genotypes of the resistant strains. Illumina sequencing was conducted to sequence the 2 b-RAD tag libraries constructed from genomic DNA samples of 3 parental strains and 2 resistant segregation populations. As a result,11 919 and 12 293 polymorphic SNP markers were obtained from parental strains AN and Ye-BN respectively. Moreover, SNPindexes related to Bm NPV resistance were analyzed on whole-genome scale for the resistant segregation populations. It was found that SNP markers related to Bm NPV resistance were distributed on multiple chromosomes in parental strains AN and Ye-BN. The top 5 chromosomes contributing to Bm NPV resistance in strain AN were chromosomes 5,10,27,23 and 4. And those in strain Ye-BN were chromosomes 4,27,15,18 and 6. On these chromosomes,many loci with high SNP index values are consistent with loci of known genes related to Bm NPV resistance. Therefore,it is suggested that the high Bm NPV resistance of AN and Ye-BN strains is related to combined functions of major resistant gene（ s） and other resistant genes.

关 键 词：家蚕 家蚕核型多角体病毒 抗性遗传 基因型组成 2b-RAD技术 

分 类 号：S881.2[农业科学—特种经济动物饲养]