Characterization of incomplete proviruses integrated in two helper-dependent hamster tumour cell lines.

The proviral structure of two helper-dependent virogenic cell lines, H-12 and H-14, originally derived from hamster tumours induced with XC RSV 940 was compared. It was established that the proviruses present in both cell lines have the pol gene and the right part of the gag gene deleted. However, H-12 cells contain one such incomplete proviral copy and H-14 cells two copies integrated at unique sites in the cellular genome.