A Moso bamboo gene VQ28 confers salt tolerance to transgenic Arabidopsis plants

Main conclusion Overexpression of PeVQ28 in Arabidopsis regulated the expression of salt/ABA-responsive genes and indicated that PeVQ28 may affect the ABA synthesis induced by stress in plants by regulating salt tolerance . Abstract Plant-specific VQ proteins, which contain a conserved short FxxhVQxhTG amino acid sequence motif, play an important role in abiotic stress responses, but their functions have not been previously studied in Moso bamboo ( Phyllostachys edulis ). In this study, real-time quantitative PCR analysis indicated that expression of PeVQ28 was induced by salt and abscisic acid stresses. A subcellular localization experiment showed that PeVQ28 was localized in the nuclei of tobacco leaf cells. Yeast two-hybrid and bimolecular fluorescence complementation analyses indicated that PeVQ28 and WRKY83 interactions occurred in the nucleus. The PeVQ28 -overexpressing Arabidopsis lines showed increased resistance to salt stress and enhanced sensitivity to ABA. Compared with wild-type plants under salt stress, PeVQ28 -transgenic plants had lower malondialdehyde and higher proline contents, which might enhance stress tolerance. Overexpression of PeVQ28 in Arabidopsis enhanced expression of salt- and ABA-responsive genes. These results suggest that PeVQ28 functions in the positive regulation of salt tolerance mediated by an ABA-dependent signaling pathway.