CePP2C19 confers tolerance to drought by regulating the ABA sensitivity in Cyperus esculentus

Abstract

Background Tiger nut (Cyperus esculentus) is widely known as an additional source of food, oil and feed worldwide. The agricultural production of tiger nut has been greatly hindered by drought stress, reducing both yield and quality. Protein phosphatase 2 C (PP2Cs) plays an important role in plant responses to drought stress however, the molecular mechanism of PP2Cs in tiger nuts still unclear. Results In this study, we identified a putative group A PP2C-encoding gene (CePP2C19) from tiger nut using transcriptome analysis, which is highly induced by drought stress. The transient expression assay suggested that CePP2C19 was localized to nucleus. Furthermore, the interaction between CePP2C19 and CePYR1, a coreceptor for ABA signaling, was first detected using a yeast two-hybrid assay and then verified using a bimolecular fluorescence complementation (BiFC) analysis. In addition, the transgenic Arabidopsis lines overexpressing CePP2C19 exhibited extreme tolerance to ABA and mannitol stresses during seed germination and root growth. At the mature stage, overexpression of CePP2C19 resulted in a higher tolerance to drought stress in transgenic Arabidopsis, as confirmed by a visible phenotype and several physiological parameters. Noticeably, the silencing of CePP2C19 by virus-induced gene silencing (VIGS) showed obvious reduction in drought tolerance in tiger nut plants. Conclusions The CePP2C19 emerges as a pivotal gene involved in the ABA signaling pathway, which likely reduce ABA sensitivity and thus enhances drought tolerance in Cyperus esculentus.

Transcriptome Analysis Reveals the Vital Role of ABA Plays in Drought Tolerance of the ABA-Insensitive Alfalfa (Medicago sativa L.)

“…In wheat, PP2C was found to interact with and dephosphorylate SnRK1.1, thereby negatively regulating drought tolerance [42]. However, PP2C19 was found to positively regulate drought tolerance in plants in Cyperus esculentus [43]. So, the specific function of PP2C for the difference between S1-0 and S1-50 needs to be further investigated.…”

Identification of the Maize PP2C Gene Family and Functional Studies on the Role of ZmPP2C15 in Drought Tolerance

“…TaPP2C-a10 acts as a negative regulator, as evidenced by Arabidopsis lines overexpressing TaPP2C-a10, which displayed early signs of wilting and death under drought stress [23]. Similarly, CePP2C19 overexpression in A. thaliana resulted in less leaf yellowing and improved growth under drought stress, whereas silencing of CePP2C19 significantly reduced drought tolerance in tiger nut plants [12]. In maize, ZmPP2C55 overexpression lines exhibited better growth under drought stress, contrasting with the wilting and yellowing observed in WT plants [19].…”

“…AtPP2CF1 overexpression in A. thaliana accelerates inflorescence stem growth by activating cell proliferation and expansion, resulting in plants with a higher biomass yield [11]. Overexpression of tiger nut CePP2C19 enhances tolerance in transgenic A. thaliana [12]. GhDRP1 is involved in the response to drought stress by regulating ABA signaling and flavonoid biosynthesis pathways, and GhDRP1 overexpression plays a negative regulatory role in the response to drought stress in cotton [13].…”

Safflower CtFLS1-Induced Drought Tolerance by Stimulating the Accumulation of Flavonols and Anthocyanins in Arabidopsis thaliana

“…For germination assay, the seeds of wild type, fls mutant, and CtFLS1 overexpression transgenic lines of Arabidopsis were sterilized and sown on 1/2 MS medium containing 0, 100, 200, 300, and 400 mM mannitol or 0, 0.5, 1, and 5 µM ABA, respectively [60]. All the plates were placed in the dark at 4 • C for 3 days (d) and then transferred to a growth room for 7 d. The seed germination rate was calculated daily, and photos were taken on the 7th day.…”