Populus × canescens PcAHL15 positively regulates salt stress tolerance in Arabidopsis thaliana

Objective This study aims to elucidate the function of Populus × canescens AT-hook motif nuclear localization protein PcAHL15 in plant salt stress response, so as to provide a theoretical basis for the genetic improvement of stress resistance in poplar.

Method The PcAHL15 gene was cloned from P. × canescens; phylogenetic analysis of PcAHL15 was conducted; the expression pattern of PcAHL15 was detected via subcellular localization and RT-qPCR; PcAHL15 was heterologously expressed in Arabidopsis thaliana, and under salt stress, phenotypic identification was performed on transgenic lines, with morphological indices, biomass accumulation, and physiological indicators measured.

Result (1) P. × canescens PcAHL15 is most closely related to P. alba and P. trichocarpa. (2) Under salt stress, the expression level of PcAHL15 in the roots, stems, and leaves of P. × canescens was significantly altered. (3) Compared with wild-type and empty vector-transformed lines, the PcAHL15-overexpressing lines exhibited alleviated leaf yellowing and wilting, increased root length, higher seed germination rate, reduced cell membrane damage, and decreased Na⁺ accumulation.

Conclusion Populus × canescens PcAHL15 positively regulates plant salt stress responses, and its overexpression confers a significant enhancement of salt tolerance in Arabidopsis.