Reference - Detail
|Author||Shingu Y, Tokai T, Agawa Y, Toyota K, Ahamed S, Kawagishi-Kobayashi M, Komatsu A, Mikawa T, Yamamoto MT, Wakasa K, Shibata T, Kusano K.|
|Title||The double-stranded break-forming activity of plant SPO11s and a novel rice SPO11 revealed by a Drosophila bioassay.|
|Journal||BMC Mol. Biol.|
BACKGROUND:SPO11 is a key protein for promoting meiotic recombination, by generating chromatin locus- and timing-specific DNA double-strand breaks (DSBs). The DSB activity of SPO11 was shown by genetic analyses, but whether SPO11 exerts DSB-forming activity by itself is still an unanswered question. DSB formation by SPO11 has not been detected by biochemical means, probably because of a lack of proper protein-folding, posttranslational modifications, and/or specific SPO11-interacting proteins required for this activity. In addition, plants have multiple SPO11-homologues.
RESULTS:To determine whether SPO11 can cleave DNA by itself, and to identify which plant SPO11 homologue cleaves DNA, we developed a Drosophila bioassay system that detects the DSB signals generated by a plant SPO11 homologue expressed ectopically. We cytologically and genetically demonstrated the DSB activities of Arabidopsis AtSPO11-1 and AtSPO11-2, which are required for meiosis, in the absence of other plant proteins. Using this bioassay, we further found that a novel SPO11-homologue, OsSPO11D, which has no counterpart in Arabidopsis, displays prominent DSB-forming activity. Quantitative analyses of the rice SPO11 transcripts revealed the specific increase in OsSPO11D mRNA in the anthers containing meiotic pollen mother cells.
CONCLUSIONS:The Drosophila bioassay system successfully demonstrated that some plant SPO11 orthologues have intrinsic DSB activities. Furthermore, we identified a novel SPO11 homologue, OsSPO11D, with robust DSB activity and a possible meiotic function.
|MeSH||Amino Acid Sequence Animals Arabidopsis / metabolism Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism Biological Assay* DNA Breaks, Double-Stranded* DNA Topoisomerases / genetics DNA Topoisomerases / metabolism Drosophila / growth & development Endodeoxyribonucleases / genetics Endodeoxyribonucleases / metabolism* Meiosis Molecular Sequence Data Oocytes / metabolism Oryza / metabolism* Plant Proteins / genetics Plant Proteins / metabolism* RNA, Messenger / metabolism Transgenes|
|WOS Category||BIOCHEMISTRY & MOLECULAR BIOLOGY|
|Drosophila||The balancer chromosomes were CyO and TM3 (Kyoto Stock Center).|