THE CLONING, SEQUENCE ANALYSIS AND EXPRESSION OF ORF2 GENE OF PORCINE CIRCOVIRUS Yu-A STRAIN

摘要

Porcine circovirus (PCV) is a small and non-enveloped virus containing a single-stranded circular DNA(1).PCV type 2(PCV2) associated with postweaning multisystemic wasting syndrome (PMWS)(2).Recently, PCV2 ORF2 has been identified as a major structural protein forming viral capsid-like particles in insect cells(3). The fact that PEPSCAN analysis performing on four dominant immunoreactive areas of ORF2 revealed the immunorelevant epitopes of some ORF2 peptides for virus type discrimination. The ORF2-derived antigens can be taken as diagnostic tools(4). In China, we have firstly successfully diagnosed some cases related with PCV2 infections by PCR. The objective of this test is to clone and to express ORF2 gene of our field isolate.