Analysis Of Complete Sequence Of Proviral DNA Of EIAV Chinese Donkey-adapted Strain And Donkey Leukocyte Attenuated Strain

EIAV is a member of lentivirus subfamily of Retroviridea, it is the pathogen of EIA. The spread of EIA was controlled successfully by the use of EIAV-DLV vaccine, which was developed by donkey leukocyte attenuated Chinese EIAV strain and widely used in late 1970s. Investigation of the immune mechanism of the attenuated EIAV vaccine would provide valuable references for the development of lentivirus vaccines.In this assay, a LA-PCR program was designed under the theories of quansispecies in order to amplify the proviral genome of DV from peripheral blood of infected horse and DLV from donkey leucocytes cultures. The proviral genome were separated into two overlaped segments which is 4.8kb and 4.3kb respectively. With the paralleled sequneing of hundreds of monoclones, ten sequences of DLV, four sequences of DV, twenty-one sequences of DLV LTR and nineteen sequences of DV LTR were obtained. A molecular clone consisted the whole sequence data of DV was constructed in this assay.The average lenth of the comlete nucleotide sequence of DLV and DV was 8236bp and 8249bp respectively. The sequences data were compared to illustrate the differences between DV and DLV. And there was averagely 2.8% differences between them. There were more differences in S2, LTR and env nucleotide sequences, and the differences were 4.1%,3.9% and 3.1%.There were more differences in S2, S3 and env amino acid sequences, and they were10.4%,5.6% and 4.8%.For the first time, the assay reported that there were at least 5 kinds of LTR in the EIAV qunsispecies which were obtain from one time cultures in vitro. There were 3 unique N-linked glycosylation sites in DV gp90, while there was only one in DLV.In generall, the quansispecies theory was used for the first time on the study of the proviral genome of EIAV in this assay. The sequences of two EIAV proviral DNA was reported in detail, and a molecular clone consisted the whole sequence data of DV was constructed. This assay would provide molecular data for the further study on the mechanisms of EIAV virulence evolution and the immune protection.