PhERF2, an ethylene-responsive element binding factor, plays an essential role in waterlogging tolerance of petunia

Abstract

Ethylene-responsive element binding factors (ERFs) are involved in regulation of various stress responses in plants, but their biological functions in waterlogging stress are largely unclear. In this study, we identified a petunia (Petunia × hybrida) ERF gene, PhERF2, that was significantly induced by waterlogging in wild-type (WT). To study the regulatory role of PhERF2 in waterlogging responses, transgenic petunia plants with RNAi silencing and overexpression of PhERF2 were generated. Compared with WT plants, PhERF2 silencing compromised the tolerance of petunia seedlings to waterlogging, shown as 96% mortality after 4 days waterlogging and 14 days recovery, while overexpression of PhERF2 improved the survival of seedlings subjected to waterlogging. PhERF2-RNAi lines exhibited earlier and more severe leaf chlorosis and necrosis than WT, whereas plants overexpressing PhERF2 showed promoted growth vigor under waterlogging. Chlorophyll content was dramatically lower in PhERF2-silenced plants than WT or overexpression plants. Typical characteristics of programmed cell death (PCD), DNA condensation, and moon-shaped nuclei were only observed in PhERF2-overexpressing lines but not in PhERF2-RNAi or control lines. Furthermore, transcript abundances of the alcoholic fermentation-related genes ADH1-1, ADH1-2, ADH1-3, PDC1, and PDC2 were reduced in PhERF2-silenced plants, but increased in PhERF2-overexpressing plants following exposure to 12-h waterlogging. In contrast, expression of the lactate fermentation-related gene LDH was up-regulated in PhERF2-silenced plants, but down-regulated in its overexpressing plants. Moreover, PhERF2 was observed to directly bind to the ADH1-2 promoter bearing ATCTA motifs. Our results demonstrate that PhERF2 contributes to petunia waterlogging tolerance through modulation of PCD and alcoholic fermentation system.

RNA-sequencing analysis revealed genes associated drought stress responses of different durations in hexaploid sweet potato

“…These results are in agreement with previous studies focused on drought stress 79 . Ethylene responsive factors (ERFs) play a regulatory role in water logging responses, are also considered in ethylene sensor promotion, and reported to play a key role in cell senescence 10 , 80 . They were down-regulated and contributed to the mitigation of drought stress in sweet potato leaves.…”

Heterologous Expression of Dehydration-Inducible MfWRKY17 of Myrothamnus Flabellifolia Confers Drought and Salt Tolerance in Arabidopsis

“…The coding sequence of MfWRKY17 was amplified by PCR using a pair of primers containing Sma I and Spe I restriction sites. The Sma I and Spe I digested amplicons were purified and inserted into pGSA1403 driven by the CaMV (Cauliflower Mosaic virus) 35S promoter [ 34 ]. The recombinant vector 35S: MfWRKY17 -pGSA1403 was transferred into the A. tumefaciens strain LBA4404 by the liquid nitrogen freezing and thawing method.…”

A Cytokinin Analog Thidiazuron Suppresses Shoot Growth in Potted Rose Plants via the Gibberellic Acid Pathway

“…The vials were flushed with compressed air that had been passed through a column filled with Ethysorb (aluminum oxide coated with KMnO 4 , Stay Fresh Ltd., London, United Kingdom) to remove hydrocarbons. The vials were sealed for 2 h and held at 25 • C, and then 3 ml of the headspace gas was injected into a Shimadzu model GC-8A gas chromatograph fitted with an aluminum oxide column and a flame ionization detector (Yin et al, 2019). The detection limit for ethylene was 5 nl/l.…”