SNI1/NSE5 is a cold-sensitive brake on class II crossovers in Arabidopsis.

SNI1/NSE5 acts as a temperature-sensitive brake on class II crossovers in Arabidopsis, with crossover rates increasing under cold conditions.

• Why it matters: Understanding how environmental factors like temperature influence meiotic recombination is crucial for insights into plant fertility and breeding. This work addresses the gap in knowledge about how temperature shifts affect crossover pathway choice.
• What they did: Using interval assays, genome-wide crossover maps, genetic mapping, and targeted genetics, the study identified a major temperature-responsive locus on chromosome 4 involving SNI1, revealing its role in crossover regulation.
• The result: Reduced SNI1 function promotes subtelomere-biased crossovers and weakens cold's suppression of class II crossovers, suggesting SNI1/NSE5 modulates crossover landscape in response to temperature changes.