Analysis of structural polypeptides of the lymphoproliferative disease virus (LPDV) of turkeys.

The polypeptide composition of the lymphoproliferative disease virus (LPDV) of turkeys was shown to comprise several polypeptides with apparent molecular weights of 76, 31, 28, 20 and 15 kDa. This polypeptide pattern is distinctly different from the protein profiles of avian leukosis viruses, reticuloendotheliosis virus, or murine leukemia viruses. Moreover, LPD virions contain 2 major structural proteins (p31 and p28), in contrast to only one major internal protein present in most other retroviruses. The 76 kDa protein was established as the major viral envelope glycoprotein. The uniqueness of the LPDV polypeptide pattern is consistent with the lack of genetic relatedness of LPDV genome to other retroviruses, establishing LPDV as a representative of a distinct group of retroviridae.