鸭腺病毒A型Hexon基因克隆与序列分析

Cloning and Sequence Analysis of Hexon Gene of Duck Adenovirus A

为明确鸭腺病毒A型Hexon基因特征及其在腺病毒科病毒分类中的作用,本研究从前期分离鉴定的一株番鸭源鸭腺病毒A型分离株(JX2016株)中分段扩增获得其Hexon基因编码区。结果发现,鸭腺病毒A型JX2016株Hexon基因编码区为2 733 bp,编码910个氨基酸,与鸭腺病毒A型(FJ12025株)核苷酸同源性最高,达99.8%;与其他分离株Hexon基因核苷酸同源性均在99.4%以上;与鸭腺病毒2型(GR株,未明确分类地位)同源性仅为54.5%;与禽腺病毒A型Phelps株(鸡源)及P29株(鹅源)的核苷酸同源性分别为53.6%和55.2%。遗传进化树分析发现,所有鸭腺病毒A型分离株在遗传进化上均处于相同的亚分支,且与绵羊腺病毒D型(OAV287株)均处于富AT腺病毒属遗传进化分支。但鸭腺病毒2型(GR株)与禽腺病毒A型Phelps株(鸡源)、P29株(鹅源)却处于同一遗传进化分支,均属于禽腺病毒属遗传进化分支。基于Hexon蛋白的遗传进化分析,建议将鸭腺病毒A型重新命名为鸭源富AT腺病毒A型,将鸭腺病毒2型重新命名为鸭源禽腺病毒。

In order to clarify the characteristics of the Hexon gene and the classification candidate of duck adenovirus A under the Adenoviridae family,the Hexon gene fragments of duck adenovirus A（ designated as strain JX2016） were amplified. The results demonstrated that the cloned Hexon gene of duck adenovirus A（ strain JX2016） was 2 733 bp in length,coding 910 amino acids. Nucleotide homology comparison showed that the strain JX2016 shared the highest nucleotide（ 99. 8%） homology with reference strain FJ12025,also displayed higher than 99.4% nucleotide homology with other duck adenovirus A reference strains. However,the nucleotide homologies with strain GR（ duck adenovirus 2,unclassified virus）,Phelps（ fowl adenovirus A） and P29（ goose adenovirus） were 54.5%,53.6% and 55.2%,respectively.The genetic evolution analysis showed that all the duck adenovirus A strains were at the same subgroup,under the same Atadenovirus genus branch with ovine atadenovirus D（ strain OAV287）. Meanwhile,the duck adenovirus 2（ strain GR） at the same branch under Aviadenovirus genus branch with fowl adenovirus A（ strain Phelps） and goose adenovirus（ strain P29）. Based on the Hexon protein genetic evolutionanalysis,we suggested renamed the duck adenovirus A as duck-origin atadenovirus and renamed the duck adenovirus 2 as duck-origin aviadenovirus.