J-亚群禽白血病JL-2株的分离鉴定

The identification of avian leukosis virus subgroup J JL-2 strain

近年来 ,J_亚群禽白血病的暴发流行在国内时有报道 ,在本研究中 ,自吉林某患病鸡群分离出一株病毒 ,采用特异性引物 ,经RT_PCR扩增出长度为 5 4 5bp的J_亚群禽白血病病毒特异性核苷酸片段 ;将病毒经SPF鸡胚成纤维细胞增殖 ,获取其前病毒DNA ,依据原型毒株HPRS_10 3cDNA序列设计并合成一对引物 ,经PCR扩增得到包括gp85、gp37、E_element基因在内的近 1.8kb的DNA片段 ,将其连到pMD18_T载体上 ,转化大肠杆菌JM10 9,培养后提取质粒分别用HindIII,BamHI进行单酶切和双酶切鉴定 ,得到了阳性重组质粒pMD18_T_JL2 /env ,核苷酸序列测定结果表明 ,该片段为J_亚群禽白血病病毒囊膜基因 ,其中亚型特异性片段gp 85和标准对照毒株HPRS_10 3的同源率为 94 % ,所编码氨基酸的同源率为 87%。

One strain of ALV-J named JL-2 was identified by reverse transcription-polymerase chain reaction(RT-PCR), This virus was propagated on the SPF CEF and harvested after 7 days' culturing. According to the sequence of prototype ALV-J virus HPRS-103 cDNA gene published, a pair of primers were designed to amplify part of the env gene which including gp85,gp37 and E-element by polymerase chain reaction(PCR).The DNA fragment obtained was inserted into pMD18-T vector and identified by single and double digestion using HindIII and BamHI, The result of sequence analysis showed that this fragment from strain JL-2 belongs to the gene of ALV-J. The sequence of gp85 of strain JL-2 shared 94 % identity with HPRS-103, and the sequence of translated amino acids shared 87 % identity accordingly.