Polypeptides of Bovine Rotavirus

Abstract

SUMMARYPolyacrylamide gel electrophoresis of bovine rotavirus or neonatal calf diarrhoea virus (NCDV) grown in cell culture resolved eight species of polypeptide. The inner shell particles contained five polypeptides and the outer shell three potypeptides. A major polypeptide of the outer shell was glycosylated. The infectivity of NCDV was enhanced by treatment with trypsin in vitro. All eight polypeptides were affected by trypsin treatment as judged by diminished intensity of polypeptide bands by radiography and several new bands appeared. The intracellular synthesis of NCDV polypeptides was studied by pulse and pulsechase experiments. Infected cells contained all eight virus capsid proteins and, in addition, three presumably virus-specific polypeptides which were non-capsid polypeptides (NCVP). There was no evidence that any of these polypeptides was processed after synthesis. It is suggested, therefore, that all these polypeptides are primary gene products.

Comparison of Bovine, Simian and Human Rotavirus Structural Glycoproteins

“…However, regardless of the cell in which it was grown, the homologous rotavirus has the same type of glycosylation pattern in its VP7. These studies may also explain why two structural glycoproteins have been observed by Matsuno & Mukoyama (1979), Cohen et al (1978), andS abara et al (1982 a): these could represent different degrees of glycosylation of VP7.…”

“…Some further studies suggested two glycoproteins (Matsuno & Mukoyama, 1979;Sabara et al, 1982 a), while other studies (Arias et at., 1982) demonstrated a single entity. The glycoprotein of simian rotavirus SA11 has been shown to exhibit structural heterogeneity (Estes et al, 1982).…”

Characterization of a second bovine rotavirus serotype

“…A similar polypeptide composition was reported for the outer shell of BI~V UK (34) and BRV NCDV (22). Some authors have described a further outer shell protein of BRV with molecular weight similar to that of VP 7 (6,19,21), whilst others have attributed this protein to the inner shell (23). Novo et al (28) and McCRAE and FAULKNER-VALLE (23) described a VP 4 protein as a prominent outer shell constituent.…”

“…The major tryptie cleavage product ofrotavirus hemogglutinin was in the past referred to as VP 5 (6,21,22). However, the fifth gene of BRV UK codes for a VP 5 polypeptide which is only weakly labelled in cells (24).…”

“…[[~vo other serotypes of BRV have been described (5,16,27,30,33,35). Prototype 1 BRV UK has been well characterized (6,21,23,24,28,34), but detailed information about other serotypes of BRV is scarce (31). In this report we give a biochemical description of the extracellular viral particles of BRV V 1005, which belongs to a second serotype of Bt~V, and its replication cycle in MA-104 cells.…”