Defective T particles of vesicular stomatitis virus: I. Preparation, morphology, and some biologic properties

Abstract

Infection of chick embryo cells with vesicular stomatitis virus under conditions of high multiplicity and serial undiluted passage (VSV up) results in two kinds of progeny: a low yield of infectious bullet-shaped (B) particles and a high yield of noninfectious (T) particles. The smaller T particles can be partially purified by rate zonal centrifugation in sucrose gradients and readily identified by electron microscopy. T particles appear almost spherical with a diameter of ~65 mμ compared with the typically cylindrical B particles with dimensions of ~65 × 180 mμ. Despite this difference in size, T is strikingly similar to B in its ultrastructure, buoyant density, antigenicity, incorporation of uridine- 3H during growth, and capacity to inhibit cellular RNA and interferon synthesis. The data strongly suggest that T is a distinct, truncated form of B which contains only a portion of the VSV genome. The accompanying paper provides proof that T is the physical equivalent of the transmissible interfering component of Cooper and Bellett (1959).