Transcriptome profiles reveal NF-YC1-regulated pathways in adaption to salt stress in Arabidopsis thaliana

Salt stress is a major abiotic stress affecting plant growth and development. Identification and characterization of genes, especially for transcription factors (TFs), can provide us a comprehensive understanding of the regulatory mechanisms of transcriptional pathways in response to salt stress. Here, we first showed that nuclear-localized transcription factor nuclear factor-Y subunit C1 (NF-YC1) was required for the salt tolerance response in Arabidopsis. Loss of function of NF-YC1 resulted in a salt-sensitive phenotype together with increased sodium (Na) content in roots and shoots, while the overexpression line could complement this phenotype. Subsequent transcriptome analysis revealed differentially expressed genes (DEGs) in WT plants and nf-yc1 mutant, independent of salt treatment. Further analysis identified two positive downstream target genes AOX3 and BGLU47, involved in the cyanide-resistant alternative respiration and lignin biosynthesis, respectively, and a negative downstream target gene, MLS, which is related to malate synthase, as being involved in these regulatory cascades controlling the salt tolerance, and these results were further confirmed by CHIP-qPCR in vivo. In conclusion, several novel pathways have been elucidated, demonstrating that NF-YC1-dependent transcriptional regulation in salt-treated Arabidopsis thaliana.