Molecular characterization and expression pattern analysis of a novel stress-responsive gene 'BeSNAC1' in Bambusa...

NAC transcription factors (TFs) are master regulators of environmental stresses exerting a crucial role in plant growth and development. However, the studies on NAC TFs from Bambusa emeiensis are scarce. In this investigation, a novel gene from B. emeiensis encoding NAC protein was cloned and characterized. The gene was isolated based on the amino acid sequence data of stress-responsive SNAC1 of rice, named 'BeSNAC1 (accession no. MG763922)'. The full-length sequence of 1681 bp was found to contain an open-reading frame of 912 bp that encode a protein of 303 amino-acid residues. The multiple protein sequence alignments unveiled that BeSNAC1 contains a typical NAC domain. Additionally, the phylogenetic analysis showed that the corresponding protein belonged to the SNAC group, as it cladded with SNAC1, HvSNAC1, TaNAC2, SbSNAC1 and ZmSNAC1 proteins. Transactivation and subcellular localization assay disclosed that BeSNAC1 is a transcriptional activator localized in the cell nucleus.Moreover, the time-dependent expression pattern of BeSNAC1 was profiled under abscisic acid (ABA), polyethylene glycol 6000 (PEG-6000), NaCl, H₂O₂ and Na₂SO₄ treatments via a quantitative real-time polymerase chain reaction. The results revealed that the expression of BeSNAC1 was significantly upregulated in all treatments, a significant difference was observed under H2O2, NaCland ABA (P 0.001) and PEG and Na2SO4 (P < 0.01) treatments, respectively. Conclusively, our findings provide evidence that 'BeSNAC1' is a nuclear protein that might act as part of the transcription regulation complex and is involved in the ABA signalling pathway and abiotic stress tolerance mechanisms in B. emeiensis.