The bamboo aquaporin gene PeTIP4;1–1 confers drought and salinity tolerance in transgenic Arabidopsis

Key message PeTIP4;1–1 , an aquaporin gene involved in bamboo shoot growth, is regulated by abiotic stresses. Overexpression of PeTIP4;1–1 confers drought and salinity tolerance in transgenic Arabidopsis . Aquaporins play a central role in numerous physiological processes throughout plant growth and development. PeTIP4;1–1 , an aquaporin gene isolated from moso bamboo ( Phyllostachys edulis ), comprises an open reading frame (ORF) of 756 bp encoding a peptide of 251 amino acids. The genomic sequence corresponding to the ORF of PeTIP4;1–1 was 1777 bp and contained three exons separated by two introns. PeTIP4;1–1 was constitutively expressed at the highest level in culms, and the expression level was elevated with increasing height of the bamboo shoot. PeTIP4;1–1 was significantly up-regulated in response to drought and salinity stresses in bamboo roots and leaves. To investigate the role of PeTIP4;1–1 in response to drought and salinity stresses, transgenic Arabidopsis plants overexpressing PeTIP4;1–1 under the control of CaMV 35S promoter were generated and subjected to morphological and physiological assays. Compared with Col-0, the transgenic plants showed enhanced tolerance to drought and salinity stresses and produced longer taproots, which had more green leaves, higher F v / F m and NPQ values, higher activities of SOD, POD and CAT, lower MDA concentration and higher water content. Transcript levels of three stress-related genes ( AtP5CS, AtNHX1 and AtLEA ) were enhanced. These results indicated that PeTIP4;1–1 might play an important function in response to drought and salinity stresses, and is a candidate gene for breeding of stress tolerance in other crops through genetic engineering.