Mutational effects of different LET radiations in rpsL transgenic Arabidopsis.
OBJECTIVE
In an effort to assess the characteristics of mutation induced by different linear energy transfer (LET) radiation in higher plants, the mutational effects of carbon-ion beams and gamma-rays were investigated in Arabidopsis.


METHODS
The rpsL (Escherichia coli ribosomal protein small subunit S12) transgenic Arabidopsis (Arabidopsis/rpsL) mutation detection system was adopted. Dry seeds of Arabidopsis/rpsL were irradiated with gamma-rays and 208-MeV carbon ions (208-MeV (12)C(5+)), and the mutation frequency and mutation spectrum were examined.


RESULTS
The frequency of mutant clones increased following irradiation with 208-MeV (12)C(5+) and gamma-rays. Mutation spectrum analysis showed that G:C to A:T transitions and >2 bp deletions/insertions were significantly induced by both 208-MeV (12)C(5+) and gamma-rays. -1 and -2 frameshift mutations were characteristic in the gamma-ray irradiated group.


CONCLUSIONS
208-MeV (12)C(5+) and gamma-rays induced different intragenic mutations in respect to the size of deletions, reflecting differences in the nature of the DNA damage induced. Our results also suggested that base substitutions derived from the generation of 8-oxoguanine were low in dry seeds. The mutation spectrum obtained in this study might have reflected the characteristic conditions of plant dry seeds such as low water content and cell proliferation activity.
Yoshihara
Ryouhei
R
Quantum Beam Science Directorate, Radiation-Applied Biology Division, Japan Atomic Energy Agency, Gunma 370-1292, Japan. yoshihara.ryohei@jaea.go.jp
Hase
Yoshihiro
Y
Sato
Ryohei
R
Takimoto
Koichi
K
Narumi
Issay
I
D017360:Arabidopsis / Q000235:genetics* / Q000528:radiation effects*; D001483:Base Sequence; D002244:Carbon; D004260:DNA Repair / Q000235:genetics / Q000528:radiation effects; D004274:DNA, Recombinant / Q000235:genetics / Q000528:radiation effects; D029968:Escherichia coli Proteins; D005720:Gamma Rays; D005798:Genes, Bacterial / Q000528:radiation effects; D018499:Linear Energy Transfer; D009154:Mutation; D030821:Plants, Genetically Modified; D011836:Radiation Tolerance; D000091243:Ribosomal Protein S9; D012269:Ribosomal Proteins / Q000235:genetics / Q000528:radiation effects
D004274:DNA, Recombinant; D029968:Escherichia coli Proteins; D000091243:Ribosomal Protein S9; D012269:Ribosomal Proteins; C000717190:RpsI protein, E coli; C506766:RpsL protein, E coli; D002244:Carbon