Soybean nuclear factor YA10 positively regulates drought resistance in transgenic Arabidopsis thaliana

Nuclear factor (NF)-Y is composed of three subunits, NF-YA, NF-YB and NF-YC, and plays important roles in the regulation of plant abiotic stress response gene expression. However, the function of individual soybean NF-YA proteins in response to drought stress is unclear. In this study, the soybean NF-YA subunit gene GmNF-YA10 was cloned, and its function in response to drought stress was identified. GmNF-YA10 is broadly expressed in soybean tissues and is specifically located in the nucleus. In soybean roots, the transcription level of the GmNF-YA10 gene was induced by polyethylene glycol (PEG)-simulated drought stress and abscisic acid (ABA) treatment. Under mannitol stress, the germination rate of transgenic Arabidopsis overexpressing GmNF-YA10 was higher than that of wild-type (WT) Arabidopsis. After drought stress, the survival rate, relative water content, ABA content, proline content and chlorophyll content of transgenic Arabidopsis overexpressing GmNF-YA10 were higher than those of WT Arabidopsis while the rate of water loss and the contents of malondialdehyde and sucrose were lower than those of WT Arabidopsis, indicating that transgenic Arabidopsis overexpressing GmNF-YA10 has better drought resistance than WT Arabidopsis. Under the ABA treatment, the root length of transgenic Arabidopsis overexpressing GmNF-YA10 was shorter than that of WT Arabidopsis and the degree of stomatal closure was greater than that of WT Arabidopsis, indicating that transgenic Arabidopsis overexpressing GmNF-YA10 was more sensitive to ABA at the post-germination stage. Transcriptome sequencing and real-time quantitative PCR analysis showed that GmNF-YA10 affected the expression of both ABA-dependent and ABA-independent signalling pathway genes. These results indicate that GmNF-YA10 significantly improves the drought resistance of transgenic Arabidopsis through ABA-dependent and ABA-independent signal transduction pathways.