Skip to main content
. Author manuscript; available in PMC: 2019 May 30.
Published in final edited form as: Cold Spring Harb Symp Quant Biol. 2017 Dec 8;82:223–234. doi: 10.1101/sqb.2017.82.034132

Figure 5. Site-specific analysis of meiotic recombination in C. elegans.

Figure 5

(A) Mos1-based single inducible DSB system. Mos1 transposons and transposases are integrated into chromosomes in a spo-11 mutant background. The Mos1 integrated strain library is available at Nemagentag (http://elegans.imbb.forth.gr/nemagenetag/). Heat shock induces expression of the transposase which excises the Mos1 transposon resulting in a single DSB at a specific genomic position. (B) The single DSB system can be used to investigate the positional effect of crossovers on meiotic chromosome segregation. Blue and red lines are paternal and maternal chromatids, respectively. The system allows us to analyze the outcome of a single crossover forming at specific chromosomal sites. A crossover at the very center region disrupts the asymmetric configuration of the bivalent resulting in premature sister chromatid separation or homolog nondisjunction. Crossovers at subtelomeres result either in potentially fragile connections that are not stably retained at the ends of very short arms or events that fail to mature into crossovers at those positions.