Genome sequencing of ion-beam-induced mutants facilitates detection of candidate genes responsible for phenotypes of mutants in rice

Publication date: Available online 21 February 2020Source: Mutation Research/Fundamental and Molecular Mechanisms of MutagenesisAuthor(s): Yutaka Oono, Hiroyuki Ichida, Ryouhei Morita, Shigeki Nozawa, Katsuya Satoh, Akemi Shimizu, Tomoko Abe, Hiroshi Kato, Yoshihiro HaseAbstractIon beams are physical mutagens used for plant and microbe breeding that cause mutations via a mechanism distinct from those of chemical mutagens or gamma rays. We utilized whole-exome sequencing of rice DNA in order to understand the properties of ion beam-induced mutations in a genome-wide manner. DNA libraries were constructed from selected carbon-ion-beam-induced rice mutants by capturing with a custom probes covering 66.3 M bases of nearly all exons and miRNAs predicted in the genome. A total of 56 mutations, including 24 single nucleotide variations, 23 deletions, and 5 insertions, were detected in five mutant rice lines (two dwarf and three early-heading-date mutants). The mutations were distributed among all 12 chromosomes, and the average mutation frequency in the M1 generation was estimated to be 2.7 × 10-7 per base. Many single base insertions and deletions were associated with homopolymeric repeats, whereas larger deletions up to seven base pairs were observed at polynucleotide repeats in the DNA sequences of the mutation sites. Of the 56 mutations, six were classified as high-impact mutations that caused a frame shift or loss of exons. A gene that was functionally related to the phe...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - Category: Cytology Source Type: research