GmNAC15 overexpression in hairy roots enhances salt tolerance in soybean

The NAC (NAM, ATAF1/2 and CUC2) transcription factor family plays a key role in plant development and responses to abiotic stress. GmNAC15 (Glyma15g40510.1), a member of the NAC transcription factor family in soybean, was functionally characterized, especially with regard to its role in salt tolerance. In the present study, qRT-PCR (quantitative reverse transcription PCR) analysis indicated that GmNAC15 was induced by salt, drought, low temperature stress, and ABA treatment in roots and leaves. GmNAC15 overexpression in soybean (Glycine max) hairy roots enhanced salt tolerance. Transgenic hairy roots improved the survival of wild leaves; however, overexpression of GmNAC15 in hairy root couldn't influnce the expression level of GmNAC15 in leaf. GmNAC15 regulates the expression levels of genes responsive to salt stress. Altogether, these results provide experimental evidence of the positive effect of GmNAC15 on salt tolerance in soybean and the potential application of genetic manipulation to enhance the salt tolerance of important crops.