RT Journal
A1 Belfield, Eric J.
A1 Gan, Xiangchao
A1 Mithani, Aziz
A1 Brown, Carly
A1 Jiang, Caifu
A1 Franklin, Keara
A1 Alvey, Elizabeth
A1 Wibowo, Anjar
A1 Jung, Marko
A1 Bailey, Kit
A1 Kalwani, Sharan
A1 Ragoussis, Jiannis
A1 Mott, Richard
A1 Harberd, Nicholas P.
T1 Genome-wide analysis of mutations in mutant lineages selected following fast-neutron irradiation mutagenesis of Arabidopsis thaliana
JF Genome Research 
JO Genome Research 
YR 2012 
FD July 01 
VO 22 
IS 7 
SP 1306 
OP 1315 
DO 10.1101/gr.131474.111 
UL http://genome.cshlp.org/content/22/7/1306.abstract 
AB Ionizing radiation has long been known to induce heritable mutagenic change in DNA sequence. However, the genome-wide effect of radiation is not well understood. Here we report the molecular properties and frequency of mutations in phenotypically selected mutant lines isolated following exposure of the genetic model flowering plant Arabidopsis thaliana to fast neutrons (FNs). Previous studies suggested that FNs predominantly induce deletions longer than a kilobase in A. thaliana. However, we found a higher frequency of single base substitution than deletion mutations. While the overall frequency and molecular spectrum of fast-neutron (FN)–induced single base substitutions differed substantially from those of “background” mutations arising spontaneously in laboratory-grown plants, G:C>A:T transitions were favored in both. We found that FN-induced G:C>A:T transitions were concentrated at pyrimidine dinucleotide sites, suggesting that FNs promote the formation of mutational covalent linkages between adjacent pyrimidine residues. In addition, we found that FNs induced more single base than large deletions, and that these single base deletions were possibly caused by replication slippage. Our observations provide an initial picture of the genome-wide molecular profile of mutations induced in A. thaliana by FN irradiation and are particularly informative of the nature and extent of genome-wide mutation in lines selected on the basis of mutant phenotypes from FN-mutagenized A. thaliana populations.