Evolution and stress response potential of the plant splicing factor U1C.

Alternative splicing is a crucial process in multicellular eukaryote, facilitated by the assembly of spliceosomal complexes comprising numerous small ribonucleoproteins. At an early stage, U1C is thought to be required for 5' splice site recognition and base pairing. However, a systematic analysis of the U1C gene family in response to developmental cues and stress conditions has not yet been conducted in plants. This study identified 114 U1C genes in 72 plant species using basic bioinformatics analyses. Phylogenetic analysis was used to compare gene and protein structures, promoter motifs, and tissue- and stress-specific expression levels, revealing their functional commonalities or diversity in response to developmental cues, such as embryonic expression, or stress treatments, including drought and heat. Fluorescence quantitative expression analysis showed that U1C gene expression changed under salt, low temperature, drought, and Cd stress in rice seedlings. However, gene expression in shoots and roots was not consistent under different stress conditions, suggesting a complex regulatory mechanism. This research provides foundational insights into the U1C gene family's role in plant development and stress responses, highlighting potential targets for future studies.