Defective interfering particles of VSVNJ (Ogden), generated by heat treatment, contain multiple internal genomic deletions.

Defective interfering (DI) particles have been isolated from a heat-resistant strain of the New Jersey (Ogden) serotype of vesicular stomatitis virus (VSV). Most of these DI particles contain various portions of all five cistrons of VSV. The two largest DI particles, NJ-121 and NJ-PG2, represent approximately 60% of the standard virus genome and contain both the positive and negative strand leader RNA templates. These two DI particles are transcriptionally active and synthesize both the positive and negative strand leader RNAs in vitro. Virion RNA probe-mRNA hybridizations and cDNA probe-virion RNA hybridizations have shown that NJ-121 contains mainly sequences from the L and G genes. In contrast, NJ-PG2 has portions of the sequences from all five genes of VSV. Smaller DI particles, NJ-121a, NJ-121b, NJ-PG1, and NJ-JM2 representing approximately 50, 38, 28, and 25% of the standard virus genome respectively, were also generated. These DI particles did not have sequences complementary to the positive strand leader RNA template. The mRNA hybridization patterns and results of the genomic RNAs hybridizing to cDNAs of N, NS, M, and G genes of these DI particles showed that they contain parts of information from all five cistrons. Most of the DI particles appear to be generated by multiple deletions throughout the standard virus genome. None of these DI particles interfered heterotypically with VSVIND-HR in BHK21, R(B77), or L2 cells. However, they interfered well with infection by VSVNJ (Hazelhurst).