Constitutive expression of a membrane-bound NAC transcription factor AmNTL1 from a desert shrub Ammopiptanthus mongolicus enhances abiotic stress tolerance of transgenic Arabidopsis

•The expression of AmNTL1 was induced by controlled cold, salt, drought and ABA stresses.•Expressing AmNTL1 in Arabidopsis enhanced tolerance to multiple abiotic stresses and the stress-induced oxidative damage.•Expressing AmNTL1 in Arabidopsis exhibited sensitivity to exogenous ABA. The NTM1-like (NTL) proteins constitute a subfamily of the NAM, ATAF and CUC (NAC) transcription factor family that regulates diverse biological processes including stress response in plants. Ammopiptanthus mongolicus is a desert shrub with very high tolerance to harsh environments. Here, an NTL-like gene, AmNTL1, was cloned from this species and its function in abiotic stress tolerance was analyzed. AmNTL1 encodes a canonical NTL protein. The full-length protein was primarily located at the plasma membrane and had transactivation activity in yeast. The expression of AmNTL1 was differentially induced by cold, salt, drought, and exogenous abscisic acid (ABA) in laboratory-cultured A. mongolicus seedlings. The expression was also induced by the cold winter and spring weather in leaves of the A. mongolicus shrubs naturally growing in the wild and was at moderate levels in lateral roots, young leaves and flower buds of the shrubs. The transgenic Arabidopsis lines constitutively expressing AmNTL1 showed enhanced tolerance to freezing, chilling, salinity, and osmotic stress as well as chilling- and salt-induced oxidative stresses. The transgenic lines also displayed ABA-sensitive phenotypes at the seed germination stage. These results suggest that AmNTL1 may play an important role in plants coping with abiotic stresses, especially cold injury, through the ABA-dependent signaling pathway.