Overexpression of MfPIP2-7 from Medicago falcata promotes cold tolerance and growth under NO3− deficiency in transgenic tobacco plants. Issue 1 (December 2016)

• Record Type: Journal Article
• Authors: Zhuo, Chunliu; Wang, Ting; Guo, Zhenfei; Lu, Shaoyun
• Is Part Of: BMC plant biology. Volume 16:Issue 1(2016)
• Page Start: 1
• Page End: 10
• Publication Date: 2016-12
• Subjects: Cold -- Hydrogen peroxide -- Medicago falcata -- MfPIP2-7 -- Nitrate reductase -- NO3− deficiency -- Tolerance; Plant molecular biology -- Periodicals; Botany -- Periodicals; 580.5
• DOI: 10.1186/s12870-016-0814-4
• Languages: English
• ISSNs: 1471-2229

Abstract

Abstract Background Plasma membrane intrinsic proteins (PIPs), which belong to aquaporins (AQPs) superfamily, are subdivided into two groups, PIP1 and PIP2, based on sequence similarity. Several PIP2s function as water channels, while PIP1s have low or no water channel activity, but have a role in water permeability through interacting with PIP2. A cold responsivePIP2 named asMfPIP2-7 was isolated fromMedicago falcata (hereafterfalcata ), a forage legume with great cold tolerance, and transgenic tobacco plants overexpressingMfPIP2-7 were analyzed in tolerance to multiple stresses including freezing, chilling, and nitrate reduction in this study. Results MfPIP2-7 transcript was induced by 4 to 12 h of cold treatment and 2 h of abscisic acid (ABA) treatment. Pretreatment with inhibitor of ABA synthesis blocked the cold inducedMfPIP2-7 transcript, indicating that ABA was involved in cold induced transcription ofMfPIP2-7 infalcata . Overexpression ofMfPIP2-7 resulted in enhanced tolerance to freezing, chilling and NO3 − deficiency in transgenic tobacco (Nicotiana tabacum L.) plants as compared with the wild type. Moreover, MfPIP2-7 was demonstrated to facilitate H2 O2 diffusion in yeast. Higher transcript levels of several stress responsive genes, such asNtERD10B, NtERD10C, NtDREB1, and2, and nitrate reductase (NR) encoding genes (NtNIA1, andNtNIA2 ) were observed in transgenic plants as compared with the wild type with dependence upon H2 O2 . In addition, NR activity was increased in transgenic plants, which led to alterations in free amino acid components and concentrations. Conclusions The results suggest that MfPIP2-7 plays an important role in plant tolerance to freezing, chilling, and NO3 − deficiency by promoted H2 O2 diffusion that in turn up-regulates expression ofNIAs and multiple stress responsive genes.