Characterization of a 70S polyuridylic acid polymerase isolated from foot-and-mouth disease virus-infected cells

Abstract

A polyuridylic acid polymerase complex isolated from foot-and-mouth disease virus-infected cells sedimented at 70S in a sucrose gradient and appeared in the exclusion volume of an agarose column whose molecular weight cutoff was 5 x 10(6). Phenol extraction of the complex yielded a heterogeneous band of virus-specific RNA and an apparently host cell-derived 4.5 to 5S RNA, both of which are essentially single stranded. Neither RNA served as a template in the cell-free enzyme reaction. Polyacrylamide gel analysis revealed five polypeptides with molecular weights of 50,000, 56,000, 60,000, 70,000, and 74,000 and with molar ratios of 1:2:2:1:1, respectively. Autoradiography showed P56 to be the only major virus-induced polypeptide; the other proteins are apparently of host cell origin. Electron microscopic examination suggested a cartwheel shape for the polymerase complex which was seen to dissociate as polyadenylic acid was added. Antibody previously shown to inhibit enzyme activity aggregated the 70S units.

Biochemical map of polypeptides specified by foot-and-mouth disease virus

“…6B, lane 5). The immunoprecipitation experiments with anti-VIAA serum support kinetic experiments and MW determinations that P61 is VIAA (P56 in 8 M urea) (19,31,33,40). Furthermore, antiserum against VIAA inhibits FMDV RNA polymerase activity (34,39).…”

Expression in cattle of epitopes of a heterologous virus using a recombinant rinderpest virus

“…Addition of an appropriate source of class II epitopes to peptide FMDV15 should result in a more effective stimulation of neutralizing antibodies. Cattle infected or vaccinated with a variety of serotypes of FMDV develop CD4 + T-cell responses directed to the FMDV RNA polymerase (3D pol ) (Foster-Cuevas, 1996 ;Collen et al, 1998 ;Foster et al, 1998) as well as serotype-cross-reactive antibodies recognizing 3D pol (Cowan & Graves, 1966 ;Fernandez et al, 1975 ;Dawe & Pinto, 1978 ;Polatnick & Wool, 1981 ;Alfonso et al, 1988), indicating that this protein may contain suitable widely recognized class II epitopes. The construct we used in these studies consisted of the FMDV 3D pol fused genetically at its carboxy terminus to peptide FMDV15.…”