Meiotic crossover recombination produces recombined chromosomes to ensure genome integrity and increase genetic diversity in progeny. Meiotic recombination initiates with the formation of numerous DNA double-strand breaks (DBSs), but only a small number of these DSBs are repaired as chromosomal exchanges of crossovers, resulting in 1~2 crossovers per chromosome pair. The distribution and frequency of DSBs and crossovers are non-uniform along chromosomes, mainly occurring at recombination hotspots found at gene promoters and terminators in euchromatin, while heterochromatin is recombination suppressed. The narrow range of crossover numbers and skewed distribution of crossovers are major obstacles to be addressed in modern plant breeding. Hence, manipulation of crossovers is of great interest in plant breeding to maximize genetic gain. We aim to understand mechanisms controlling the number and position of crossovers in plants. To achieve this, we use advanced methods of recombination measurements, including genome-wide crossover mapping and fluorescent crossover reporter-based genetic screening of high crossover rate mutants. Our studies on meiotic recombination in the model plant Arabidopsis will help accelerate plant breeding for food security by recombining or mapping useful genetic and epigenetic variations in crop varieties.

• ㆍMechanism of meiotic crossover pattering in plants
• ㆍEpigenetic control of meiotic recombination in plants
• ㆍControl of plant meiotic crossover number and position in plants

• ㆍKim H, et al., (2024) Control of meiotic crossover interference by a proteolytic chaperone network. Nature Plants 41, e109958
• ㆍKim J, et al., (2022) Arabidopsis HEAT SHOCK FACTOR BINDING PROTEIN is required to limit meiotic crossovers and HEI10 transcription. EMBO Journal 41, e109958
• ㆍDageswaran D, et al., (2021) HIGH CROSSOVER RATE1 encodes PROTEIN PHOSPHATASE X1 and restricts meiotic crossovers in Arabidopsis. Nature Plants 7, 452-467
• ㆍLim E, et al., (2020) DeepTetrad: high-throughput image analysis of meiotic tetrads by deep learning in Arabidopsis thaliana. Plant Journal 101, 473-483
• ㆍChoi K, et al., (2018) Nucleosomes and DNA methylation shape meiotic DSB frequency in Arabidopsis transposons and gene regulatory regions. Genome Research 28, 532-546
• ㆍChoi K, et al., (2016) Recombination rate heterogeneity within Arabidopsis disease resistance genes. PLoS genetics 14, e1006179
• ㆍChoi K, et al., (2016) Regulation of microRNA-mediated developmental changes by SWR1 chromatin remodelling complex in Arabidopsis thaliana. Plant Physiology 171, 1128-43
• ㆍChoi K, et al., (2013) Arabidopsis meiotic crossover hot spots overlap with H2A.Z nucleosomes at gene promoters. Nature genetics 45, 1327-1336
• ㆍChoi K, et al., (2011) The FRIGIDA complex activates transcription of FLC, a strong flowering repressor in Arabidopsis, by recruiting chromatin modification factors. Plant Cell 23, 289-303
• ㆍChoi K, et al., (2007) Arabidopsis homologs of components of SWR1 complex regulate flowering and plant development. Development 134, 1931-1941
• ㆍChoi K, et al., (2005) SUPPRESSOR OF FRIGIDA3 encodes a nuclear ACTIN-RELATED PROTEIN6 required for floral repression in Arabidopsis. Plant Cell 17, 2647-2660

• ㆍB.S., Seoul National University, Seoul, Korea (2000)
• ㆍM.S., Seoul National University, Seoul, Korea (2002)
• ㆍPh.D., Seoul National University, Seoul, Korea (2007)

• ㆍ2007-2010 : Postdoctoral research fellow, Seoul National University, Korea
• ㆍ2010-2012 : Postdoctoral research EMBO fellow, University of Cambridge, UK
• ㆍ2012-2016 : Postdoctoral research associate, University of Cambridge, UK
• ㆍ2016-2017 : Research Professor, Gyeongsang National University, Korea
• ㆍ2017.2-Present : Faculty, Department of Life Sciences, POSTECH

• ㆍGenetic identification of anti-crossover factors in plants
• ㆍGenome-wide mapping of meiotic DSBs and crossovers in Arabidopsis
• ㆍGenome-wide mapping of historical recombination hotspots in Arabidopsis
• ㆍElucidation of a role for histone variant H2A.Z in promoting crossovers in Arabidopsis

• ㆍEMBO Long-Term Fellowship (2009-2010)
• ㆍSuh Kyungbae Foundation Young Investigator Fellowship (2017-2022)
• ㆍPOSTECH Mueunjae Distinguished Professor (2023-2025)