The splicing factor UAP1 exhibits a conserved function in cold stress responses among three dicotyledonous species

Here, we identified the spliceosome U4/U6.U5 tri-snRNP-associated protein 1 (UAP1) as a pivotal negative regulator of cold tolerance in both tomato (Solanum lycopersicum) and soybean (Glycine max). Using CRISPR/Cas9-mediated gene editing, we generated UAP1 knockout orthologs in three dicotyledonous species: tomato, soybean and Arabidopsis.

The sluap1 and gmuap1 mutants exhibited significantly enhanced cold resilience, characterized by reduced membrane damage, lower reactive oxygen species accumulation, and higher survival rates after cold stress. To elucidate the underlying molecular mechanism, we further characterized the uap1 mutants in Arabidopsis, which similarly displayed a cold-tolerant phenotype. Transcriptome-wide analysis revealed that the loss of AtUAP1 results in widespread differential alternative splicing under cold stress.