The structural constituents of the type-C RNA viral membrane have been investigated. Among the gag gene-coded proteins of Rauscher murine leukemia virus (MuL virus), only p15 exhibited hydrophobic properties characteristic of a membrane protein. Biochemical analysis of Rauscher- MuL virus p15 indicated the absolute requirement of detergents or phospholipids for maintenance of its native state in aqueous solutions. Moreover, this protein specifically interacted with the micellar structures of several nonionic surfactants and small phospholipid vesicles. Rauscher- MuL virus p15 was shown to be located within the virion in a partially exposed position as determined by its accessibility to lactoperoxidase, but not to immunoglobulin molecules. These findings, along with its biochemical properties, indicate that Rauscher-MuL virus p15 is a constituent of the type-C viral membrane. Immunologic characterization of Rauscher-MuL virus p15 allowed the detection of antigenically related proteins in other mammalian type-C virus. M(r) = 15,000 proteins isolated from 3 prototype mouse type-C viruses, were shown to possess hydrophobic properties and antigenic determinants related to those of Rauscher-MuL virus p15. Moreover, each could be specifically radiolabeled in the intact virion. The conservation of the biochemical and immunologic properties of the gag gene-coded p15 among known mammalian type-C viruses suggests an important role of this protein in the viral membrane.
|Number of pages||7|
|Journal||Journal of Biological Chemistry|
|State||Published - 1978|