Molecular genetic characterization and haplotype diversity of swine leukocyte antigen in Chinese Rongshui miniature pigs
Molecular genetic characterization and haplotype diversity of swine leukocyte antigen in Chinese Rongshui miniature pigs
复制标题
中国融水小型猪白细胞抗原分子遗传特征及单倍型多样性
DOI：
10.1016/j.molimm.2019.05.009
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发表时间：
2019-08-01
影响因子：
3.6
通讯作者：
Chen, Hongyan
中科院分区：
文献类型：
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作者：
Gao, Caixia;Xin, Chang;Chen, Hongyan
融水小型猪是我国畜禽疾病防治研究的重要模式动物。高度多态性的猪白细胞抗原（SLA）一直是相当大的兴趣，因为特别是SLA单倍型和传染病之间的强，可重复的关联的焦点。本研究采用RT-PCR序列分型技术和PCR序列特异性引物，在融水小型猪8个多态性SLA位点（SLA-1、SLA-3、SLA-2、SLA-6、DRB 1、DQA和DQB 1）上鉴定出42个等位基因，分别代表7个Ⅰ类和6个Ⅱ类单倍型。官方名称由国际动物遗传学会SLA命名委员会指定。其中7种Ⅰ类单倍型（Hp-5b.0、86.0、87.0、88.0、89.0、90.0和91.0）和4种Ⅱ类单倍型（Hp-0.18b、0.19c、0.41和0.47）在其它猪种中未见报道。对所鉴定的等位基因的分子遗传特性、遗传多样性以及融水小型猪SLA单倍型多样性进行了综合分析。SLA-1和SLA-6基因处于正选择状态，SLA-2基因处于中性选择状态，其余5个基因处于纯化选择状态。高度多态性的新等位基因可以通过核苷酸突变、插入和缺失以及片段重组来获得，并且等位基因基于序列差异和肽结合基序而不是猪品种来分离。通过等位基因/基因转换和重组产生SLA单倍型多样性。这些结果将有助于阐明不同SLA单倍型猪抗病性差异的分子遗传机制。
The Rongshui miniature pig is an important model animal for studying livestock disease prevention and control in China. The highly polymorphic swine leukocyte antigen (SLA) has been the focus of considerable interest because of the strong, reproducible associations between particular SLA haplotypes and infectious diseases. In this study, we identified 42 alleles at eight polymorphic SLA loci (SLA-1, SLA-3, SLA-2, SLA-6, DRA, DRB1, DQA, and DQB1) representing seven class I and six class II haplotypes using reverse transcription-polymerase chain reaction (RT-PCR) sequence-based typing and PCR-sequence specific primers in Rongshui miniature pigs. The official names were designated by the SLA Nomenclature Committee of the International Society for Animal Genetics. Seven class I haplotypes, Hp-5b.0, 86.0, 87.0, 88.0, 89.0, 90.0 and 91.0, and four class II haplotypes, Hp-0.18b, 0.19c, 0.41 and 0.47, had not previously been reported in other pig breeds. We also comprehensively analyzed the molecular genetic characterization and phylogenies of the identified alleles and the SLA haplotype diversity in Rongshui miniature pigs. SLA-1 and SLA-6 genes were under positive selection, while SLA-2 was under neutral selection, and the other five genes were under purifying selection. The highly polymorphic new alleles may be derived by nucleotide mutations, insertions and deletions, and fragment recombination, and alleles segregated based on sequence differences and peptide-binding motifs, rather than on pig breed. SLA haplotype diversity was generated by allele/gene conversion and recombination. These results will be helpful for elucidating the molecular genetic mechanisms influencing differential disease resistance among pigs with different SLA haplotypes.