Czech J. Genet. Plant Breed., 2016, 52(2):77-82 | DOI: 10.17221/155/2015-CJGPB

Enhanced tolerance to low-K⁺ stress in tobacco plants, that ectopically express the CBL-interacting protein kinase CIPK23 geneShort Communication

Gang XUE¹, Li-Ming LU², Tie-Zhao YANG¹, Xiao-Hui LI¹, Xue-Xia XING¹, Shi-Xiao XU¹

¹ College of Tobacco Science, Henan Agricultural University, Zhengzhou, P.R. China

² College of Agronomy, Sichuan Agricultural University, Ya'an, P.R. China

Tobacco (Nicotiana tabacum) has a relatively high requirement for potassium (K⁺). However, the molecular basis of tolerance to low-K⁺ stresses in tobacco still remains unknown. Here, we report the role of a member of the A. thaliana CBL (calcineurin B-like) interacting protein kinase (CIPK) family, AtCIPK23, in low-K⁺ stress responses in tobacco. Molecular analyses revealed that the AtCIPK23 gene was successfully transferred into a tobacco cultivar K326 via Agrobacterium tumefaciens-mediated transformation. Overexpression of AtCIPK23 in tobacco resulted in increased low-K⁺ tolerance, which was demonstrated by higher dry biomass, longer primary root length, higher K⁺ content and better growth status of transgenic tobacco plants compared to controls when both were treated in low-K⁺ MS medium and low-K⁺ hydroponics. Moreover, transgenic lines conferred tolerance to low-K⁺ stress by increasing the K⁺ uptake rate under low-K⁺ conditions. Taken together, these results provide evidence that AtCIPK23 may be involved in the CBL-CIPK signalling network in tobacco responses to low-K⁺ stress.

Keywords: AtCIPK23; K+ uptake; low-K+ tolerance; potassium; tobacco

Published: June 30, 2016  Show citation