Proposed structure of two defective viral DNA oligomers produced in 3T3 cells transformed by the ts-a mutant of polyoma virus.

The various oligomeric viral DNA species produced at 32 C by two related syblines of ts-a-transformed mouse 3T3 cells were characterized. Results from the analysis of the cleavage products observed after digestion with restriction endonucleases from Haemophilus parainfluenzae, Escherichia coli RI, and Haemophilus suis are consistent with the assumption that in both sublines, the major oligomeric component is a dimer from which a segment of different length is deleted. The major oligomeric (27S) component in subline 1 was estimated to be 1.77 times the size of the viral monomer, and the major (25.5S) component in subline 15 was estimated to be 1.54 times the size of the viral monomer. These size estimates were confirmed by electron micrograph measurements. The larger oligomers produced by both sublines were found to be multiples of the major oligomeric component of each subline.