Enhanced micronucleus formation in the descendants of -ray-irradiated tobacco cells; Evidence for radiation-induced genomic instability in plant cells

Yokota, Yuichiro; Funayama, Tomoo; Hase, Yoshihiro; Hamada, Nobuyuki*; Kobayashi, Yasuhiko; Tanaka, Atsushi; Narumi, Issei

Ionizing radiation-induced genomic instability has been documented in various end points such as chromosomal aberrations and mutations, which arises in the descendants of irradiated mammalian or yeast cells many generations after the initial insult. This study aimed at addressing radiation-induced genomic instability in higher plant tobacco cells. We thus investigated micronucleus (MN) formation and cell proliferation in tobacco cells irradiated with -rays and their descendants. The descendants that have undergone at least 22 generations after irradiation still showed a two-fold MN frequency compared to sham-irradiated cells. This is the direct evidence for radiation-induced genomic instability in tobacco cells.