Natural variation identifies SNI1, the SMC5/6 component, as a modifier of meiotic crossover in <i>Arabidopsis</i>
Longfei Zhu, Nadia Fernández‐Jiménez, Maja Szymańska-Lejman, Alexandre Pelé, Charles J. Underwood, Heïdi Serra, Christophe Lambing, Julia Dluzewska, Tomasz Bieluszewski, Mónica Pradillo, Ian R. Henderson, Piotr A. Ziółkowski
Abstract
Significance Meiotic recombination plays a fundamental role in shaping genetic diversity in eukaryotes. Extensive variation in crossover rate exists between populations and species. The identity of modifier loci and their roles in genome evolution remain incompletely understood. We explored natural variation in Arabidopsis crossover and identified SNI1 as the causal gene underlying a major modifier locus. To date, SNI1 had no known role in crossover. SNI1 is a component of the SMC5/6 complex that is closely related to cohesin and condensin. Arabidopsis sni1 and other SMC5/6 mutants show similar effects on the interference-independent crossover pathway. Hence, our findings demonstrate that the SMC5/6 complex, which is known for its role in DNA damage repair, is also important for control of meiotic crossover.