Rauscher leukemia virus populations enriched for "immature" virions contain increased amounts of P70, the gag gene product

Abstract

Preparations of Rauscher leukemia virus (RLV) that had relatively low, intermediate or high levels of P70 (the gag gene product) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis were examined by thin-section EM. A direct correlation was found between the number of immature virions in the RLV preparation and the amount of P70. The immature core subparticles isolated from these RLV preparations could themselves be further subdivided into 2 categories, based on their P70 content and negative stain morphology. Those immature cores containing a high P70/p30 ratio predominantly (85%) exhibited a highly coiled internal structure; those with a relatively low level of P70 exhibited less of an internal coiled structure.