Genetic Analysis of Adenovirus Type 2. Pleiotropic Effects in an Assembly Mutant

Abstract

Summary A new temperature sensitive mutant of adenovirus type 2 was isolated and characterized. H2ts48 is DNA positive but fails to synthesize stable 95K, 80K and Va (Pre-VI) polypeptides. In addition, many polypeptides exhibit reduced stability during pulse-chase experiments. No virion particles of any type are assembled although a new type of intranuclear core-like structure was observed in thin sections by electron microscopy. Hexon polypeptides (120K) are synthesized as demonstrated by SDS-polyacrylamide gel electrophoresis, but immunofluorescence, immunodiffusion and sucrose velocity gradient analyses show that no hexon capsomere antigens (360K) are assembled. Similarly, fibre polypeptides are synthesized normally, but the immunological and sedimentation properties of fibre are abnormal. Because this mutant failed to complement several complementing adenovirus mutants, and depressed the growth of wild type virus, it was concluded that ts48 may be a novel, trans-dominant mutation.