8-Azaguanine-resistant variants of cultured cells of Haplopappus gracilis

Abstract

Cultured cell lines of Haplopappus gracilis resistant to the purine analog 8-azaguanine (AG) have been isolated. One such line is 50 times more resistant to the drug than are wild-type cells. This line of AG-resistant cells also exhibits increased resistance to 8-azaadenine, but it responds to kinetin in a manner identical with that of wild-type cells. The resistance phenotype is stable for many generations in the absence of selection. In cultures of wild-type or mutant cells, more than 95% of cells are diploid.