HIGH CROSSOVER RATE1 restricts the number of meiotic crossovers in Arabidopsis
- HIGH CROSSOVER RATE1 restricts the number of meiotic crossovers in Arabidopsis
- Date Issued
- The Korea Genome Organization (한국유전체학회)
- Meiotic crossover creates new combinations of genetic variation and ensures balanced chromosome transmission. Crossover numbers per meiosis are tightly restricted in most eukaryotes, despite a large excess of initiating DNA double-strand break precursors. The majority of crossovers in plants are dependent on the Class I interfering repair pathway. A minority of crossovers are formed by the Class II non-interfering pathway. The Class II repair pathway is normally limited by multiple anti-recombination pathways. However, similar pathways that limit Class I interfering crossovers are not known. To identify repressors of crossovers, we performed a forward genetic screen using fluorescent crossover reporters, to identify mutants with changed recombination frequency. This screen identified the HIGH CROSSOVER RATE1 (HCR1) gene as repressing crossovers. Using genome-wide analysis we show that crossovers are most strongly increased in the euchromatic chromosome arms of hcr1. We observe a significant increase in MLH1 foci and the interference ratio in hcr1, consistent with a predominant effect on the Class I pathway. We used 2-hybrid and in planta assays to demonstrate physical interaction between HCR1 and multiple proteins within the Class I interfering pathway, including HEI10, PTD, and MSH5. Our data identify HCR1 as limiting the number of interfering Class I crossovers in plants. We propose that HCR1 acts in opposition to pro-recombination DNA repair or cell division kinases, in order to limit crossover numbers per meiosis.
- Article Type
- The 29th International KOGO Annual Conference, 2020-10-15
- Files in This Item:
- There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.