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A great new paper:
Genome-wide analysis of mutations in mutant lineages selected following fast-neutron irradiation mutagenesis of Arabidopsis thaliana
Genome Res. July 2012 22: 1306-1315. http://genome.cshlp.org/content/22/7/1306.full.pdf+html
Ionizing radiation has long been known to induce heritable mutagenic change in DNA sequence. However, the genomewide 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 inA. 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.
The paper sequences the genome of six independent plants and describes the mutations induced by radiation. The paper uses a software package called Iterative Read-Mapping and Realignment (IMR) v0.3.0 (http://mus.well.ox.ac.uk/19genomes/IMR-DENOM/) that allows efficient detection of mutations quickly.
Genome-wide analysis of mutations in mutant lineages selected following fast-neutron irradiation mutagenesis of Arabidopsis thaliana
Genome Res. July 2012 22: 1306-1315. http://genome.cshlp.org/content/22/7/1306.full.pdf+html
Ionizing radiation has long been known to induce heritable mutagenic change in DNA sequence. However, the genomewide 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 inA. 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.
The paper sequences the genome of six independent plants and describes the mutations induced by radiation. The paper uses a software package called Iterative Read-Mapping and Realignment (IMR) v0.3.0 (http://mus.well.ox.ac.uk/19genomes/IMR-DENOM/) that allows efficient detection of mutations quickly.