Cell lines of Nicotiana tabacum exhibiting a resistance to nucleic acid base analogues were studied. The selection of resistant cells was attempted with or without prior mutagenic treatment. Cell lines resistant to 8-azaguanine (AG) were obtained by enrichment cultures on media containing the analogue. In the presence of 5-bromodeoxyuridine (BUdR), used at concentrations which had no limiting effect on growth, the morphology of the wild-type cells was systematically modified. The most obvious effect observed was the complete loss of the lamellar system and of pigments in the plastids. From the cultures bleached by BUdR, permanent green cell lines were selected which remained resistant to the bleaching effect of this analogue. © 1973.
Lescure, A. M. (1973). Selection of markers of resistance to base-analogues in somatic cell cultures of nicotiana tabacum. Plant Science Letters, 1(9), 375–383. https://doi.org/10.1016/0304-4211(73)90062-X